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HomeMy WebLinkAboutTIR-4032SURFACE WATER UTILITYrstraka 10/17/2018DEVELOPMENT ENGINEERINGbbannwarth 10/17/2018 Cobalt Geosciences P.O. Box 82243 Kenmore, Washington 98028 (206) 331-1097 October 5, 2017 Mr. Hakam Singh Hakamseattle@gmail.com RE: Retaining Wall Design Christelle Ridge Plat SE 95th Way and Duvall Avenue NE Renton, Washington Dear Mr. Singh, In accordance with your authorization, Cobalt Geosciences, LLC (Cobalt) has prepared retaining wall designs for the project located southwest of the intersection of SE 95th Way and Duvall Avenue NE in Renton, Washington. We have reviewed a plan sheet that shows the location of various retaining walls along between building lots, along property lines, and along the primary access roadway. An additional plan sheet provides generalized details of reinforced fill and cut slope rockery walls. Wall Options at Lot 5 The section A-A’ shown on sheet G04 shows two 8 feet tall fill rockeries separated by a 2 feet distance and located 3 feet from a new residence. From our review, this scenario is only present along the west side of Lot 5. We recommend that any wall or walls located west of the house on Lot 5 consist of a cast-in-place concrete wall or a geogrid reinforced modular block wall. We do not recommend constructing reinforced fill rockeries in this area. If a modular block wall is considered, it should have a maximum height of 12 feet. This is due to the total setback of 10 feet for the residence from the property line (limited space for reinforcement). Also, we recommend a maximum slope of 1H:1V extending from the outside (west) base of the building foundation to the toe of the new wall. This may require several feet of additional footing embedment along the west building line. Depending on the final design layouts and elevations, a cast-in-place concrete wall may be designed to support surcharge loads associated with a new residence. Also, this type of wall construction may be completed for quickly than a modular block wall. The following sections provide design information for both wall type options for Lot 5 and a concrete wall along the access roadway. October 5, 2017 Page 2 of 6 Retaining Wall Design Concrete Retaining Wall Parameters A variable height concrete retaining wall will be constructed along the west side of the access roadway, in the area of Lot 1, Tract C, and Lot 3. The wall will be up to 22 feet in height. We have previously observed the native soils in this area and they consist of dense to very dense native glacial till and outwash. A cast-in-place wall would be suitable along the west property line in Lot 5. We would anticipate a level to slight backslope and a wall height of 12 to 16 feet. The following table, titled Wall Design Criteria, presents the recommended soil related design parameters for retaining walls with a level backslope. Contact Cobalt if an alternate retaining wall system is used. Wall Design Criteria “At-rest” Conditions (Lateral Earth Pressure – EFD+) 55 pcf (Equivalent Fluid Density) “Active” Conditions (Lateral Earth Pressure – EFD+) 35 pcf (Equivalent Fluid Density) Seismic Increase for “At-rest” Conditions (Lateral Earth Pressure) 22H* (Uniform Distribution) Seismic Increase for “Active” Conditions (Lateral Earth Pressure) 7H* (Uniform Distribution) Passive Earth Pressure on Low Side of Wall (Allowable, includes F.S. = 1.5) Neglect upper 2 feet, then 300 pcf EFD+ *H is the height of the wall; Increase based on one in 2,500 year seismic event (2 percent probability of being exceeded in 50 years), + EFD – Equivalent Fluid Density The stated lateral earth pressures do not include the effects of hydrostatic pressure generated by water accumulation behind the retaining walls. Uniform horizontal lateral active and at-rest pressures on the retaining walls from vertical surcharges behind the wall may be calculated using active and at-rest lateral earth pressure coefficients of 0.3 and 0.5, respectively (if necessary for the vaults). The soil unit weight of 125 pcf may be used to calculate vertical earth surcharges. To reduce the potential for the buildup of water pressure against the walls, continuous footing drains (with cleanouts) should be provided at the bases of the walls. The footing drains should consist of a minimum 4-inch diameter perforated pipe, sloped to drain, with perforations placed down and enveloped by a minimum 6 inches of pea gravel in all directions. The wall backfill should consist of free-draining granular material. All wall backfill should contain less than 5 percent fines (passing the U.S. Standard No. 200 Sieve) based upon the fraction passing the U.S. Standard No. 4 Sieve with at least 30 percent of the material October 5, 2017 Page 3 of 6 Retaining Wall Design being retained on the U.S. Standard No. 4 Sieve. The primary purpose of the free- draining material is the reduction of hydrostatic pressure. Some potential for the moisture to contact the back face of the wall may exist, even with treatment, which may require that more extensive waterproofing be specified for walls which require interior moisture sensitive finishes. Minimum 3 inch diameter weep holes, placed approximately 8 feet on center, should be considered near the base of the wall in addition to a footing drain system. We recommend that the backfill be compacted to at least 90 percent of the maximum dry density based on ASTM Test Method D1557. In place density tests should be performed to verify adequate compaction. Soil compactors place transient surcharges on the backfill. Consequently, only light hand operated equipment is recommended within 3 feet of walls so that excessive stress is not imposed on the walls. Geogrid Reinforced Modular Block Wall Design Parameters The following soil parameters were used in our design: Soil Type Friction Angle Cohesion Unit Weight Retained Soil 32 degrees 0 psf 125 pcf Native Glacial Till 36 degrees 0 psf 125 pcf psf = pounds per square foot pcf = pounds per cubic foot General Wall Subgrade Preparation & Structural Fills To prepare the wall areas for construction, all vegetation, organic surface soils, and other deleterious materials including any existing structures, foundations or abandoned utility lines should be stripped and removed from the new development areas. Organic topsoil will not be suitable for use as structural fill, but may be used for limited depths in non- structural areas (landscaping areas). If excessively soft or yielding areas are present, and cannot be stabilized in place by compaction, they should be cut to firm bearing soil and filled to grade with structural fill. If the depth to remove the unsuitable soil is excessive, we should be contacted to provide recommendations as necessary for the successful completion of the walls, or to re-evaluate the wall designs based on actual site conditions. A representative of Cobalt Geosciences should observe the foundation subgrade compaction operations to verify that stable subgrades are achieved for support of structural elements. All fill placed behind the walls, regardless of whether or not it is in the reinforced backfill zone, must be compacted as structural fill. The native soils at the site contain a sufficient enough percentage of fines that will make them difficult, if not impossible, to compact as structural fill when they are over-optimum in moisture content. Therefore, we recommend importing a granular soil for use in geogrid reinforced walls that meets the following gradation requirements: October 5, 2017 Page 4 of 6 Retaining Wall Design U. S. Sieve Size Percent Passing 6 inches 100 No. 4 75 maximum No. 200 5 maximum* * Based on the 0.25 inch fraction Prior to use, Cobalt Geosciences should examine and test all materials to be imported to the site for use as structural fill. Structural fill should be placed in uniform loose layers not exceeding 10 inches and compacted to a minimum of 95 percent of the maximum dry density as determined by American Society for Testing and Materials (ASTM) Test Designation D-1557 (Modified Proctor). The moisture content of the soil at the time of compaction should be within two percent of its optimum, as determined by the ASTM standard. Wall Construction We recommend the following recommendations be incorporated into the construction of the wall: • We recommend using the Standard Unit Keystone Blocks. • The wall should have a maximum total height of no more than 12 feet with 1.3 feet of embedment (effective height of 10.7 feet). • If a cap block is used, it must be entirely above ground and as such will not be considered in the total height of the wall. • Minimum 3 feet of level bench in front of the wall with a maximum slope of 3H:1V beyond this area. • A 6-inch thick layer of 5/8 inch minus or 1-1/4 inch minus crushed rock should be placed and compacted along the wall subgrade to provide a leveling course. • The soil used in the reinforcement zone must consist of structural fill as described in the General Wall Subgrade Preparation section of this report. • A layer of separation fabric should be placed over the top of the 12-inch wide drainage zone. No other separation fabric should be used. • The upper 12 inches of fill may contain organic-laced soil for landscaping (if proposed). • The wall drain should outfall through the base of the wall at a convenient location (1 block above the base block) and discharge either into the sites' storm water system, or onto a quarry rock pads located below the wall. October 5, 2017 Page 5 of 6 Retaining Wall Design Wall Design Wall calculations are attached at the end of the report. For the purpose of our design, we used the Keystone Standard Unit blocks and a 1 inch offset per block (batter). The following geogrid schedule indicates the number of geogrid layers and length for the retaining wall: GEOGRID SCHEDULE TOTAL WALL HEIGHT (FT.) NO. OF GEOGRID LAYERS GEOGRID LENGTH (FT.) 12 8 10.0 Geogrid should consist of Mirafi 10XT. Equivalent grids may be acceptable for use; however, we should be provided with the type and strength parameters prior to confirming suitability. Geogrid should be placed between the third and fourth blocks from the keyway and every two blocks thereafter up to finish grade. Wall Drainage To guard against hydrostatic pressure development, drainage must be installed behind the wall. We recommend that wall drainage consist of a minimum 12 inches of clean 5/8 inch to 1 inch crushed rock with less than three percent fines placed against the back of the wall. In addition, a drainage collector system consisting of 4-inch perforated PVC pipe should be placed behind the wall to provide an outlet for any accumulated water. The drain should be provided with cleanouts at each end, and within 5 feet of any wall turn. These cleanouts should be serviced at least once every year. The wall drainage material should be capped at the ground surface with 1-foot of relatively impermeable soil to prevent surface intrusion into the drainage zone. The wall drain should outfall through the base of the wall and discharge onto a quarry rock pad located on the slope face. Limitations Earthwork construction is characterized by the presence of a calculated risk that soil and groundwater conditions have been fully revealed by the original evaluation. This risk is derived from the practical necessity of basing interpretations and design conclusions on limited observation of the earth. The recommendations made in this report are based on the assumption that soil conditions do not vary significantly from those disclosed during our field evaluation. If any variations or undesirable conditions are encountered during construction, Cobalt Geosciences should be notified so that supplemental recommendations can be made. October 5, 2017 Page 6 of 6 Retaining Wall Design The conclusions of this report are based on the limited information provided regarding the proposed construction. If the proposed construction is relocated or redesigned, the conclusions in this report may not be valid. Cobalt Geosciences should be notified of any changes so that the recommendations can be reviewed and re-evaluated. Cobalt Geosciences should monitor all aspects of wall construction. The information presented herein is based upon professional interpretation utilizing standard practices and a degree of conservatism deemed proper for this project. We emphasize that this report is valid for this project as outlined above, and should not be used for any other site. Sincerely, Cobalt Geosciences, LLC Phil Haberman, PE, LG, LEG Principal PH/sc Attachment: Wall Design Output File Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:SEP 14,2017 Description.... This Wall in File: c:\users\phaberman\desktop\christelle.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMARegistration #: RP-1110505 RP9.27 Thumbnail Criteria Wall height (retained height), ft 12.00 Backfill slope Level Backfill angle 0.0 Embedment 1.3 Soil data External Soil, Phi_e 36 External soil density (In situ), pcf 125 Internal Soil, Phi_i 32 Internal soil density, pcf 125 Wall Soil Friction Angle 21 K_a(Horiz) 0.22 Stability Overturning ratio 10.75 Sliding ratio 6.12 Overturning moment, ft-lbs 7,026 Resisting moment, ft-lbs 75,506 Total lateral/sliding force, lbs 1,757 Sliding Resistance, ft 10,756.46 Total vertical force, lbs 14,805 Base length, ft 9.93 Eccentricity on base, ft 0.34 Effective base length, ft 9.25 Soil bearing pressure, psf 1,600.38 Allowable soil bearing, psf 38,457.94 Soil Bearing Ratio 24.03 Loading Dead load, psf 0 Live load, psf 0 Seismic Design Kh 0.00 Segmental block data Vendor selection Keystone Retaining Wall Systems Vendor web address www.keystonewalls.com Block selection type Standard 18" Block height, in 8.00 Block depth, in 18.00 Offset per block, in 1.00 Batter angle 7.13 Wall weight, psf 180.00 Hinge height, ft 12.00 Geogrid material Vendor Selection Mirafi Geogrid Vendor web address www.mirafi.com Geogrid type Miragrid 10XT LTDS 4969.14 Factor of safety 1.50 LTADS 3312.76 Peak connection equation 1125 + 0.31N Peak connection maximum 3876 Serviceability connection equation 1125 + 0.31N Serviceability connection maximum 3876Wall Analysis Table: Block Layer Height above base Tension Embed Vert S. F. Seismic Le NServPeak Connection StaticDecInFt 18 0" 12.0012' 16 8 8" 10.67 48 1199.410' 799.6 1.26 240 16.62 14 7 4" 9.33 96 1273.8 9' 849.2 1.26 480 8.82 12 6 0" 8.00 144 1348.2 8' 898.8 1.26 720 6.23 10 5 8" 6.67 192 1422.6 6' 948.4 1.26 960 4.93 8 4 4" 5.33 241 1497.0 5' 998.0 1.26 1,200 4.15 6 3 0" 4.00 289 1571.4 4' 1047.6 1.26 1,440 3.63 4 2 8" 2.67 337 1645.8 2' 1097.2 1.26 1,680 3.26 2 1 4" 1.33 385 1720.2 1' 1146.8 1.26 1,920 2.98 Base 0" 0.00 0' 2,160 Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:SEP 14,2017 Description.... This Wall in File: c:\users\phaberman\desktop\christelle.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMARegistration #: RP-1110505 RP9.27 Summary: Resisting / Overturning Resisting Moments Distance, ft Moment, ft-lbs Wall 1.50 2,160 3,240 Reinf. earth 5.72 72,266 12,645 8.65Sloped 0 0 7.21 0Dead load 0 0 7.21Live load 0 75,506 1,757 4.00 7,026 0 6.00 0 Total 14,805 Item Force, lbs Overturning Moments 0 6.00 0 Item Force, lbs Distance, ft Moment, ft-lbs 0 0.00 0 Earth 0 0.00 0 Surcharge, DL 0 0 0.00 Surcharge, LL Seismic, Wall Seismic, Reinf. Seismic, Sloped soil Seismic, Exterior 0.00 0 0 Total 1,757 7,026 Overturning Ratio 10.75 ASSUMPTIONS AND CRITERIA USED 1. References used include Design Manual for Segmental Retaining Walls, 2nd Edition, and Segmental Retaining Walls – Seismic Design Manual, 1st Edition, both by NCMA. 2. Blocks are all same size and uniform offsets (batter) for full wall height.3. Coulomb earth pressure theory used for earth pressures and failure plane angle.4. Refer to geotechnical report for backfill material, compaction, and other design data and recommendations. 5. Cap blocks if used are above the retained height and are neglected in this design.6. Geogrid LTDS and connection values for block vendors obtained from ICC Evaluation Service (ES Legacy Reports) or as provided by vendors. Since these may change or be updated, verification of values is recommended. 7. Block sizes obtained from vendors’ literature and may vary with locality. 8. Geogrid layers are equally spaced vertically, all same length, and laid horizontally. 9. Average weight of block and cell infill assumed to be 120 pcf.10. See vendor web sites (on input screen) for more information and specifications.11. Design height is limited to 16 feet or 24 blocks, whichever is less. Contact vendor for higher designs or special conditions.12. Seismic design is per Seismic Design Manual cited above. Also see Methodology/Seismic Design in User’s Manual. 13. Vendor specifications or project specifications, whichever is most restrictive, to be followed for construction procedures. 14. Add notes and details for proper drainage. 15. See User’s Manual Design Example #10 for methodology and sample verification calculations. 16. Final design responsibility is with the project Engineer-of-Record. Cobalt Geosciences P.O. Box 82243 Kenmore, Washington 98028 (206) 331-1097 February 13, 2018 Mr. Hakam Singh hakamseattle@gmail.com RE: Retaining Wall Recommendations Proposed Residential Plat Duvall Avenue NE and SE 95th Way Renton, Washington Dear Mr. Singh, In accordance with your authorization, Cobalt Geosciences, LLC (Cobalt) has prepared this letter report to present retaining wall design recommendations for the proposed residential plat located southwest of the intersection of SE 95th Way and Duvall Avenue NE in Renton, Washington (Figure 1). We previously provided a geotechnical evaluation of the existing lock and load wall dated January 5, 2017. Access Roadway Retaining Wall There is a very steep excavated slope along the west side of the access roadway within the site, generally along the east sides of Lot 1, Tract C, and Lot 3 (Figure 2). We understand that a modular block retaining wall with geogrid reinforcement will be constructed in this area. The construction will require additional excavation work to create adequate space for the reinforced structural fill. Wall heights are expected to be up to 22 feet with an overall length of about 200 feet. The soils observed in the cut and in test pits we conducted above the cut consist of dense to very dense glacial till. General Wall Subgrade Preparation To prepare the wall areas for construction, all vegetation, organic surface soils, and other deleterious materials should be stripped and removed from the wall keyway. Organic topsoil will not be suitable for use as structural fill, but may be used in non-structural areas. The area behind the proposed wall will require benching to create adequate space for geogrid reinforced fill. Benching should consist of vertical steps with a maximum height of 6 feet and minimum lateral length of 6 feet. The wall keyway and benches should be excavated into dense to very dense native soils and verified by the geotechnical engineer. February 13, 2018 Page 2 of 6 Retaining Wall Recommendations Design Parameters The following soil parameters were used in our designs: Soil Type Friction Angle Cohesion Unit Weight Structural Fill 34 degrees 0 psf 130 pcf Native Soils 42 degrees 0 psf 130 pcf psf = pounds per square foot pcf = pounds per cubic foot All fill placed behind the walls, regardless of whether or not it is in the reinforced backfill zone, must be compacted as structural fill. The native soils at the site contain a sufficient enough percentage of fines that will make them difficult, if not impossible, to compact as structural fill when they are over-optimum in moisture content. Therefore, we recommend importing a granular soil for use in geogrid reinforced walls that meets the following gradation requirements: U. S. Sieve Size Percent Passing 6 inches 100 No. 4 75 maximum No. 200 5 maximum* * Based on the 0.25 inch fraction Prior to use, Cobalt Geosciences should examine and test all materials to be imported to the site for use as structural fill. Native soils may be suitable for use as structural fill provided they are within 3 percent of the optimum moisture. If soils with greater than 10 percent fines are used as structural fill, we recommend placement of a double-drain system (see drainage section). Design Elements The new retaining wall should consist of the Keystone Standard II Blocks, or an equivalent approved by us. The new Keystone Block walls should be constructed as Mechanically Stabilized Earth (MSE) walls with segmental block facing. The new retaining walls should be constructed according to the manufacturers' specifications and the recommendations provided in this report. We have designed the walls based on a 1-inch offset per block. We recommend the following recommendations be incorporated into the construction of the wall: • We recommend using the Standard II Keystone Blocks. • If a cap block is used, it must be entirely above ground and as such will not be considered in the total height of the wall. • A minimum of 1 foot of toe embedment is necessary for erosion protection and stability purposes. February 13, 2018 Page 3 of 6 Retaining Wall Recommendations • A 6-inch thick layer of 5/8 inch minus or 1-1/4 inch minus crushed rock should be placed and compacted along the wall subgrade to provide a leveling course. • Geogrid reinforcement should consist of Synteen SF 110 or an equivalent approved by us. • The soil used in the reinforcement zone must consist of structural fill as described in the General Wall Subgrade Preparation section of this report. Cement treated fill and/or native glacial till soils may be suitable provided Cobalt reviews the methodology and observes/test fill placement. • A layer of separation fabric should be placed over the top of the 12-inch wide drainage zone. No other separation fabric should be used. • The upper 12 inches of fill may contain organic-laced soil for landscaping (if proposed). • The wall drains should outfall through the base of the wall at convenient locations and discharge either into a tightline extending into the detention pond or into a shallow rock protected ditch below the wall. Minimum outflows every 40 feet along the wall at the base. • Density testing of structural fill should be performed per manufacturer’s recommendations. At least one test per lift is typically recommended. • At least one direct shear analysis and three proctor-sieve analyses should be performed for every1,000 cubic yards of structural reinforced fill. Geogrid Schedule The following geogrid schedule can be used to determine the appropriate geogrid length for the changes in the wall height and location: GEOGRID SCHEDULE TOTAL WALL HEIGHT (FT.) NUMBER OF GEOGRID LAYERS GEOGRID LENGTH (FT.) 6 2 6.1 8 3 7.6 10 4 8.6 12 5 10.1 14 6 11.6 February 13, 2018 Page 4 of 6 Retaining Wall Recommendations 16 7 13.6 18 8 15.1 20* 14 17.1 22* 15 17.6 *Wall heights equal to or over 19 feet must have geogrid placed every two blocks instead of the typical 3 blocks (two feet). All wall heights designed for a maximum 4H:1V backslope. Except for wall heights of 19 feet or more, geogrid should be placed every 2 feet vertically (3 blocks) from the base up to finish grade elevations with the first layer above the lowest or second to lowest block as shown on the diagrams. Geogrid should be pinned between blocks and overlap onto adjacent geogrids at least 12 inches. Grid should be staked flat as fill is placed. Note: Grid lengths and number of grids should not be interpolated from the table data. We should be contacted to provide information for intermediate heights, if they are required. Wall Drainage To guard against hydrostatic pressure development, drainage must be installed behind the wall. We recommend that wall drainage consist of a minimum 18 inches of clean 5/8 inch to 1 inch crushed rock with less than three percent fines placed against the back of the wall. In addition, a drainage collector system consisting of 4-inch perforated PVC pipe should be placed behind the wall to provide an outlet for any accumulated water. Perpendicular outlet drains should be placed below and through the wall no greater than 25 feet on center along the wall lengths. The drain should be provided with cleanouts at each end, and within 5 feet of any wall turn. These cleanouts should be serviced at least once every year. The wall drainage material should be capped at the ground surface with 1-foot of relatively impermeable soil to prevent surface intrusion into the drainage zone. The wall drains should outfall through the base of the wall and be tightlined into the stormwater detention pond. If native glacial till soils are used as structural fill, we recommend placement of an additional drainage system to intercept groundwater and infiltrating surface water from areas west of the wall for wall heights greater than 10 feet. This should consist of a minimum 12 inch thickness of clean angular rock or imported fill with less than 5 percent fines placed over the benched native soils. Fill should be placed over the top of each bench and extend up the vertical cuts at each bench (Figure 3). Drainage placement should be monitored by the geotechnical engineer. February 13, 2018 Page 5 of 6 Retaining Wall Recommendations Foundation Setbacks and Considerations We recommend that any new residences be set back from the face of the wall a lateral distance equal to the wall height. The lateral distance could be reduced if foundation embedment depths are increased. We can provide location-specific recommendations during construction. Foundation elements should bear on medium dense or firmer native soils or on properly compacted structural fill placed on the suitable native soils. See the previous geotechnical report for more information on foundation preparation. Erosion and Sediment Control Erosion and sediment control (ESC) is used to reduce the transportation of eroded sediment to wetlands, streams, lakes, drainage systems, and adjacent properties. Erosion and sediment control measures should be implemented and these measures should be in general accordance with local regulations. At a minimum, the following basic recommendations should be incorporated into the design of the erosion and sediment control features for the site: • Schedule the soil, foundation, utility, and other work requiring excavation or the disturbance of the site soils, to take place during the dry season (generally May through September). However, provided precautions are taken using Best Management Practices (BMP’s), grading activities can be completed during the wet season (generally October through April). • All site work should be completed and stabilized as quickly as possible. • Additional perimeter erosion and sediment control features may be required to reduce the possibility of sediment entering the surface water. This may include additional silt fences, silt fences with a higher Apparent Opening Size (AOS), construction of a berm, or other filtration systems. • Any runoff generated by dewatering discharge should be treated through construction of a sediment trap if there is sufficient space. If space is limited other filtration methods will need to be incorporated. Limitations Earthwork construction is characterized by the presence of a calculated risk that soil and groundwater conditions have been fully revealed by the original evaluation. This risk is derived from the practical necessity of basing interpretations and design conclusions on limited observation of the earth. The recommendations made in this report are based on the assumption that soil conditions consist of glacially consolidated till or outwash materials. If any variations or undesirable conditions are encountered during construction, Cobalt Geosciences should be notified so that supplemental/alternative recommendations can be made. The conclusions of this report are based on the limited information provided regarding the proposed construction. If the proposed construction is relocated or redesigned, the February 13, 2018 Page 6 of 6 Retaining Wall Recommendations conclusions in this report may not be valid. Cobalt Geosciences should be notified of any changes so that the recommendations can be reviewed and re-evaluated. Cobalt Geosciences should monitor all aspects of wall construction. This report was prepared for the exclusive use of Hakam Singh and his appointed consultants. Any use of this report or the material contained herein by third parties, or for other than the intended purpose, should first be approved in writing by Cobalt Geosciences. The information presented herein is based upon professional interpretation utilizing standard practices and a degree of conservatism deemed proper for this project. We emphasize that this report is valid for this project as outlined above, and should not be used for any other site. Sincerely, Cobalt Geosciences, LLC Phil Haberman, PE, LG, LEG Principal PH/sc Figure 1; Vicinity Map Figure 2; Site Plan Figure 3; Drain System and Benching Attachments: Wall Schematics and Designs N VICINITY MAP FIGURE 1 P.O. Box 82243 Kenmore, WA 98028 (206) 331-1097 cobaltgeo@gmail.comCobalt Geosciences Project Location Renton WASHINGTON SITE Proposed 20-Lot Plat Renton, Washington SITE PLAN FIGURE 2 P.O. Box 82243 Kenmore, WA 98028 (206) 331-1097 cobaltgeo@gmail.comCobalt Geosciences Proposed 20-Lot Plat Renton, Washington NTP-1 TP-5 TP-2 TP-6 TP-7 TP-4 TP-1 TP-8 TP-3 DRAIN & BENCHING FIGURE 3 P.O. Box 82243 Kenmore, WA 98028 (206) 331-1097 cobaltgeo@gmail.comCobalt Geosciences Proposed 20-Lot Plat Renton, Washington Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Thumbnail Criteria Wall height (retained height), ft 6.00 Backfill slope 4:1 Backfill angle 14.0 Embedment 1.0 Soil data External Soil, Phi_e 42 External soil density (In situ), pcf 130 Internal Soil, Phi_i 34 Internal soil density, pcf 130 Wall Soil Friction Angle 23 K_a(Horiz) 0.23 K_AE(Horiz) 0.41 If seismic included the min. OTM and sliding ratios may be 1.1 per IBC '09, 1807.2.3. Stability Overturning ratio 5.56 Sliding ratio 4.60 Overturning moment, ft-lbs 2,958 Resisting moment, ft-lbs 16,447 Total lateral/sliding force, lbs 973 Sliding Resistance, ft 4,478.42 Total vertical force, lbs 4,974 Base length, ft 6.06 Eccentricity on base, ft 0.32 Effective base length, ft 5.42 Soil bearing pressure, psf 916.93 Allowable soil bearing, psf 0.00 Soil Bearing Ratio 0.00 Loading Dead load, psf 0 Live load, psf 0 Seismic Design Kh 0.05 Segmental block data Vendor selection Keystone Retaining Wall Systems Vendor web address www.keystonewalls.com Block selection type Standard 18" Block height, in 8.00 Block depth, in 18.00 Offset per block, in 1.00 Batter angle 7.13 Wall weight, psf 180.00 Hinge height, ft 12.00 Geogrid material Vendor Selection Synteen Vendor web address www.synteen.com Geogrid type Synteen SF 110 LTDS 5652.52 Factor of safety 1.50 LTADS 3768.35 Peak connection equation 3885 + 0.2N Peak connection maximum 5456 Serviceability connection equation 1534 + 0.11N Serviceability connection maximum 2427Wall Analysis Table: Block Layer Height above base Tension Embed Vert S. F. Seismic Le NServPeak Connection StaticDecInFt 9 0" 6.00 6' 5 2 4" 3.33 185 1586.8 3'2654.0 1.90 480 195 4.18 2 1 4" 1.33 231 1626.4 1'2702.0 1.44 840 93 5.02 Base 0" 0.00 0'1,080 Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Summary: Resisting / Overturning Resisting Moments Distance, ft Moment, ft-lbs Wall 1.12 1,080 1,215 Reinf. earth 3.78 13,445 3,557 5.31Sloped 1,788 337 4.53 0Dead load 0 0 4.53Live load 0 16,447 561 2.38 1,336 0 3.57 0 Total 4,974 Item Force, lbs Overturning Moments 0 3.57 0 Item Force, lbs Distance, ft Moment, ft-lbs 54 3.00 162 Earth 59 3.00 176 Surcharge, DL 2 11 6.12 Surcharge, LL Seismic, Wall Seismic, Reinf. Seismic, Sloped soil Seismic, Exterior 4.28 297 1,273 Total 973 2,958 Overturning Ratio 5.56 ASSUMPTIONS AND CRITERIA USED 1. References used include Design Manual for Segmental Retaining Walls, 2nd Edition, and Segmental Retaining Walls – Seismic Design Manual, 1st Edition, both by NCMA. 2. Blocks are all same size and uniform offsets (batter) for full wall height.3. Coulomb earth pressure theory used for earth pressures and failure plane angle.4. Refer to geotechnical report for backfill material, compaction, and other design data and recommendations.5. Cap blocks if used are above the retained height and are neglected in this design.6. Geogrid LTDS and connection values for block vendors obtained from ICC Evaluation Service (ES Legacy Reports) or as provided by vendors. Since these may change or be updated, verification of values is recommended. 7. Block sizes obtained from vendors’ literature and may vary with locality. 8. Geogrid layers are equally spaced vertically, all same length, and laid horizontally. 9. Average weight of block and cell infill assumed to be 120 pcf.10. See vendor web sites (on input screen) for more information and specifications.11. Design height is limited to 16 feet or 24 blocks, whichever is less. Contact vendor for higher designs or special conditions.12. Seismic design is per Seismic Design Manual cited above. Also see Methodology/Seismic Design in User’s Manual. 13. Vendor specifications or project specifications, whichever is most restrictive, to be followed for construction procedures. 14. Add notes and details for proper drainage. 15. See User’s Manual Design Example #10 for methodology and sample verification calculations. 16. Final design responsibility is with the project Engineer-of-Record. Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Thumbnail Criteria Wall height (retained height), ft 8.00 Backfill slope 4:1 Backfill angle 14.0 Embedment 1.0 Soil data External Soil, Phi_e 42 External soil density (In situ), pcf 130 Internal Soil, Phi_i 34 Internal soil density, pcf 130 Wall Soil Friction Angle 23 K_a(Horiz) 0.23 K_AE(Horiz) 0.41 If seismic included the min. OTM and sliding ratios may be 1.1 per IBC '09, 1807.2.3. Stability Overturning ratio 4.88 Sliding ratio 4.33 Overturning moment, ft-lbs 7,024 Resisting moment, ft-lbs 34,254 Total lateral/sliding force, lbs 1,732 Sliding Resistance, ft 7,507.17 Total vertical force, lbs 8,338 Base length, ft 7.56 Eccentricity on base, ft 0.51 Effective base length, ft 6.53 Soil bearing pressure, psf 1,276.42 Allowable soil bearing, psf 0.00 Soil Bearing Ratio 0.00 Loading Dead load, psf 0 Live load, psf 0 Seismic Design Kh 0.05 Segmental block data Vendor selection Keystone Retaining Wall Systems Vendor web address www.keystonewalls.com Block selection type Standard 18" Block height, in 8.00 Block depth, in 18.00 Offset per block, in 1.00 Batter angle 7.13 Wall weight, psf 180.00 Hinge height, ft 12.00 Geogrid material Vendor Selection Synteen Vendor web address www.synteen.com Geogrid type Synteen SF 110 LTDS 5652.52 Factor of safety 1.50 LTADS 3768.35 Peak connection equation 3885 + 0.2N Peak connection maximum 5456 Serviceability connection equation 1534 + 0.11N Serviceability connection maximum 2427Wall Analysis Table: Block Layer Height above base Tension Embed Vert S. F. Seismic Le NServPeak Connection StaticDecInFt 12 0" 8.00 8' 8 3 4" 5.33 185 1586.8 5'2654.0 2.11 480 283 3.40 5 2 4" 3.33 277 1626.4 3'2702.0 1.63 840 186 3.51 2 1 4" 1.33 330 1666.0 1'2750.0 1.42 1,200 108 3.80 Base 0" 0.00 0'1,440 Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Summary: Resisting / Overturning Resisting Moments Distance, ft Moment, ft-lbs Wall 1.25 1,440 1,800 Reinf. earth 4.53 28,550 6,302 6.56Sloped 3,904 595 5.53 0Dead load 0 0 5.53Live load 0 34,254 997 3.17 3,161 0 4.76 0 Total 8,338 Item Force, lbs Overturning Moments 0 4.76 0 Item Force, lbs Distance, ft Moment, ft-lbs 72 4.00 288 Earth 130 4.00 520 Surcharge, DL 5 42 8.21 Surcharge, LL Seismic, Wall Seismic, Reinf. Seismic, Sloped soil Seismic, Exterior 5.71 528 3,013 Total 1,732 7,024 Overturning Ratio 4.88 ASSUMPTIONS AND CRITERIA USED 1. References used include Design Manual for Segmental Retaining Walls, 2nd Edition, and Segmental Retaining Walls – Seismic Design Manual, 1st Edition, both by NCMA. 2. Blocks are all same size and uniform offsets (batter) for full wall height.3. Coulomb earth pressure theory used for earth pressures and failure plane angle.4. Refer to geotechnical report for backfill material, compaction, and other design data and recommendations.5. Cap blocks if used are above the retained height and are neglected in this design.6. Geogrid LTDS and connection values for block vendors obtained from ICC Evaluation Service (ES Legacy Reports) or as provided by vendors. Since these may change or be updated, verification of values is recommended. 7. Block sizes obtained from vendors’ literature and may vary with locality. 8. Geogrid layers are equally spaced vertically, all same length, and laid horizontally. 9. Average weight of block and cell infill assumed to be 120 pcf.10. See vendor web sites (on input screen) for more information and specifications.11. Design height is limited to 16 feet or 24 blocks, whichever is less. Contact vendor for higher designs or special conditions.12. Seismic design is per Seismic Design Manual cited above. Also see Methodology/Seismic Design in User’s Manual. 13. Vendor specifications or project specifications, whichever is most restrictive, to be followed for construction procedures. 14. Add notes and details for proper drainage. 15. See User’s Manual Design Example #10 for methodology and sample verification calculations. 16. Final design responsibility is with the project Engineer-of-Record. Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Thumbnail Criteria Wall height (retained height), ft 10.00 Backfill slope 4:1 Backfill angle 14.0 Embedment 1.0 Soil data External Soil, Phi_e 42 External soil density (In situ), pcf 130 Internal Soil, Phi_i 34 Internal soil density, pcf 130 Wall Soil Friction Angle 23 K_a(Horiz) 0.23 K_AE(Horiz) 0.41 If seismic included the min. OTM and sliding ratios may be 1.1 per IBC '09, 1807.2.3. Stability Overturning ratio 4.09 Sliding ratio 3.99 Overturning moment, ft-lbs 13,362 Resisting moment, ft-lbs 54,683 Total lateral/sliding force, lbs 2,659 Sliding Resistance, ft 10,611.97 Total vertical force, lbs 11,786 Base length, ft 8.56 Eccentricity on base, ft 0.77 Effective base length, ft 7.01 Soil bearing pressure, psf 1,680.82 Allowable soil bearing, psf 0.00 Soil Bearing Ratio 0.00 Loading Dead load, psf 0 Live load, psf 0 Seismic Design Kh 0.05 Segmental block data Vendor selection Keystone Retaining Wall Systems Vendor web address www.keystonewalls.com Block selection type Standard 18" Block height, in 8.00 Block depth, in 18.00 Offset per block, in 1.00 Batter angle 7.13 Wall weight, psf 180.00 Hinge height, ft 12.00 Geogrid material Vendor Selection Synteen Vendor web address www.synteen.com Geogrid type Synteen SF 110 LTDS 5652.52 Factor of safety 1.50 LTADS 3768.35 Peak connection equation 3885 + 0.2N Peak connection maximum 5456 Serviceability connection equation 1534 + 0.11N Serviceability connection maximum 2427Wall Analysis Table: Block Layer Height above base Tension Embed Vert S. F. Seismic Le NServPeak Connection StaticDecInFt 15 0" 10.0010' 11 4 4" 7.33 185 1586.8 7'2654.0 2.32 480 370 2.86 8 3 4" 5.33 277 1626.4 5'2702.0 1.73 840 261 3.02 5 2 4" 3.33 396 1666.0 3'2750.0 1.57 1,200 205 2.77 2 1 4" 1.33 429 1705.6 1'2798.0 1.40 1,560 124 3.09 Base 0" 0.00 0'1,800 Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Summary: Resisting / Overturning Resisting Moments Distance, ft Moment, ft-lbs Wall 1.37 1,800 2,475 Reinf. earth 5.03 46,165 9,178 7.48Sloped 6,042 808 6.28 0Dead load 0 0 6.28Live load 0 54,683 1,524 3.92 5,976 0 5.88 0 Total 11,786 Item Force, lbs Overturning Moments 0 5.88 0 Item Force, lbs Distance, ft Moment, ft-lbs 90 5.00 450 Earth 228 5.00 1,138 Surcharge, DL 10 102 10.29 Surcharge, LL Seismic, Wall Seismic, Reinf. Seismic, Sloped soil Seismic, Exterior 7.06 807 5,697 Total 2,659 13,362 Overturning Ratio 4.09 ASSUMPTIONS AND CRITERIA USED 1. References used include Design Manual for Segmental Retaining Walls, 2nd Edition, and Segmental Retaining Walls – Seismic Design Manual, 1st Edition, both by NCMA. 2. Blocks are all same size and uniform offsets (batter) for full wall height.3. Coulomb earth pressure theory used for earth pressures and failure plane angle.4. Refer to geotechnical report for backfill material, compaction, and other design data and recommendations.5. Cap blocks if used are above the retained height and are neglected in this design.6. Geogrid LTDS and connection values for block vendors obtained from ICC Evaluation Service (ES Legacy Reports) or as provided by vendors. Since these may change or be updated, verification of values is recommended. 7. Block sizes obtained from vendors’ literature and may vary with locality. 8. Geogrid layers are equally spaced vertically, all same length, and laid horizontally. 9. Average weight of block and cell infill assumed to be 120 pcf.10. See vendor web sites (on input screen) for more information and specifications.11. Design height is limited to 16 feet or 24 blocks, whichever is less. Contact vendor for higher designs or special conditions.12. Seismic design is per Seismic Design Manual cited above. Also see Methodology/Seismic Design in User’s Manual. 13. Vendor specifications or project specifications, whichever is most restrictive, to be followed for construction procedures. 14. Add notes and details for proper drainage. 15. See User’s Manual Design Example #10 for methodology and sample verification calculations. 16. Final design responsibility is with the project Engineer-of-Record. Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Thumbnail Criteria Wall height (retained height), ft 12.00 Backfill slope 4:1 Backfill angle 14.0 Embedment 1.0 Soil data External Soil, Phi_e 42 External soil density (In situ), pcf 130 Internal Soil, Phi_i 34 Internal soil density, pcf 130 Wall Soil Friction Angle 23 K_a(Horiz) 0.23 K_AE(Horiz) 0.41 If seismic included the min. OTM and sliding ratios may be 1.1 per IBC '09, 1807.2.3. Stability Overturning ratio 3.91 Sliding ratio 3.91 Overturning moment, ft-lbs 23,222 Resisting moment, ft-lbs 90,797 Total lateral/sliding force, lbs 3,844 Sliding Resistance, ft 15,037.73 Total vertical force, lbs 16,701 Base length, ft 10.06 Eccentricity on base, ft 0.98 Effective base length, ft 8.09 Soil bearing pressure, psf 2,063.82 Allowable soil bearing, psf 0.00 Soil Bearing Ratio 0.00 Loading Dead load, psf 0 Live load, psf 0 Seismic Design Kh 0.05 Segmental block data Vendor selection Keystone Retaining Wall Systems Vendor web address www.keystonewalls.com Block selection type Standard 18" Block height, in 8.00 Block depth, in 18.00 Offset per block, in 1.00 Batter angle 7.13 Wall weight, psf 180.00 Hinge height, ft 12.00 Geogrid material Vendor Selection Synteen Vendor web address www.synteen.com Geogrid type Synteen SF 110 LTDS 5652.52 Factor of safety 1.50 LTADS 3768.35 Peak connection equation 3885 + 0.2N Peak connection maximum 5456 Serviceability connection equation 1534 + 0.11N Serviceability connection maximum 2427Wall Analysis Table: Block Layer Height above base Tension Embed Vert S. F. Seismic Le NServPeak Connection StaticDecInFt 18 0" 12.0012' 14 5 4" 9.33 185 1586.8 9'2654.0 2.52 480 457 2.47 11 4 4" 7.33 277 1626.4 7'2702.0 1.83 840 336 2.65 8 3 4" 5.33 396 1666.0 5'2750.0 1.64 1,200 280 2.47 5 2 4" 3.33 515 1705.6 3'2798.0 1.54 1,560 223 2.31 2 1 4" 1.33 528 1745.2 1'2846.0 1.40 1,920 140 2.62 Base 0" 0.00 0'2,160 Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Summary: Resisting / Overturning Resisting Moments Distance, ft Moment, ft-lbs Wall 1.50 2,160 3,240 Reinf. earth 5.78 77,184 13,354 8.74Sloped 10,373 1,187 7.28 0Dead load 0 0 7.28Live load 0 90,797 2,202 4.71 10,374 0 7.07 0 Total 16,701 Item Force, lbs Overturning Moments 0 7.07 0 Item Force, lbs Distance, ft Moment, ft-lbs 108 6.00 648 Earth 351 6.00 2,106 Surcharge, DL 16 203 12.37 Surcharge, LL Seismic, Wall Seismic, Reinf. Seismic, Sloped soil Seismic, Exterior 8.48 1,166 9,890 Total 3,844 23,222 Overturning Ratio 3.91 ASSUMPTIONS AND CRITERIA USED 1. References used include Design Manual for Segmental Retaining Walls, 2nd Edition, and Segmental Retaining Walls – Seismic Design Manual, 1st Edition, both by NCMA. 2. Blocks are all same size and uniform offsets (batter) for full wall height.3. Coulomb earth pressure theory used for earth pressures and failure plane angle.4. Refer to geotechnical report for backfill material, compaction, and other design data and recommendations.5. Cap blocks if used are above the retained height and are neglected in this design.6. Geogrid LTDS and connection values for block vendors obtained from ICC Evaluation Service (ES Legacy Reports) or as provided by vendors. Since these may change or be updated, verification of values is recommended. 7. Block sizes obtained from vendors’ literature and may vary with locality. 8. Geogrid layers are equally spaced vertically, all same length, and laid horizontally. 9. Average weight of block and cell infill assumed to be 120 pcf.10. See vendor web sites (on input screen) for more information and specifications.11. Design height is limited to 16 feet or 24 blocks, whichever is less. Contact vendor for higher designs or special conditions.12. Seismic design is per Seismic Design Manual cited above. Also see Methodology/Seismic Design in User’s Manual. 13. Vendor specifications or project specifications, whichever is most restrictive, to be followed for construction procedures. 14. Add notes and details for proper drainage. 15. See User’s Manual Design Example #10 for methodology and sample verification calculations. 16. Final design responsibility is with the project Engineer-of-Record. Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Thumbnail Criteria Wall height (retained height), ft 14.00 Backfill slope 4:1 Backfill angle 14.0 Embedment 1.0 Soil data External Soil, Phi_e 42 External soil density (In situ), pcf 130 Internal Soil, Phi_i 34 Internal soil density, pcf 130 Wall Soil Friction Angle 23 K_a(Horiz) 0.23 K_AE(Horiz) 0.41 If seismic included the min. OTM and sliding ratios may be 1.1 per IBC '09, 1807.2.3. Stability Overturning ratio 3.78 Sliding ratio 3.86 Overturning moment, ft-lbs 37,026 Resisting moment, ft-lbs 140039 Total lateral/sliding force, lbs 5,246 Sliding Resistance, ft 20,231.48 Total vertical force, lbs 22,469 Base length, ft 11.56 Eccentricity on base, ft 1.20 Effective base length, ft 9.17 Soil bearing pressure, psf 2,450.52 Allowable soil bearing, psf 0.00 Soil Bearing Ratio 0.00 Loading Dead load, psf 0 Live load, psf 0 Seismic Design Kh 0.05 Segmental block data Vendor selection Keystone Retaining Wall Systems Vendor web address www.keystonewalls.com Block selection type Standard 18" Block height, in 8.00 Block depth, in 18.00 Offset per block, in 1.00 Batter angle 7.13 Wall weight, psf 180.00 Hinge height, ft 12.00 Geogrid material Vendor Selection Synteen Vendor web address www.synteen.com Geogrid type Synteen SF 110 LTDS 5652.52 Factor of safety 1.50 LTADS 3768.35 Peak connection equation 3885 + 0.2N Peak connection maximum 5456 Serviceability connection equation 1534 + 0.11N Serviceability connection maximum 2427Wall Analysis Table: Block Layer Height above base Tension Embed Vert S. F. Seismic Le NServPeak Connection StaticDecInFt 21 0" 14.0014' 17 6 4" 11.33 185 1586.811'2654.0 2.73 480 544 2.18 14 5 4" 9.33 277 1626.4 9'2702.0 1.93 840 410 2.37 11 4 4" 7.33 396 1666.0 7'2750.0 1.71 1,200 354 2.22 8 3 4" 5.33 515 1705.6 5'2798.0 1.59 1,560 298 2.10 5 2 4" 3.33 633 1745.2 3'2846.0 1.52 1,920 242 1.99 2 1 4" 1.33 627 1784.8 1'2894.0 1.39 2,280 155 2.28 Base 0" 0.00 0'2,520 Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Summary: Resisting / Overturning Resisting Moments Distance, ft Moment, ft-lbs Wall 1.62 2,520 4,095 Reinf. earth 6.53 119,559 18,309 9.99Sloped 16,385 1,640 8.28 0Dead load 0 0 8.28Live load 0 140,039 3,004 5.50 16,529 0 8.25 0 Total 22,469 Item Force, lbs Overturning Moments 0 8.25 0 Item Force, lbs Distance, ft Moment, ft-lbs 126 7.00 882 Earth 501 7.00 3,504 Surcharge, DL 25 354 14.45 Surcharge, LL Seismic, Wall Seismic, Reinf. Seismic, Sloped soil Seismic, Exterior 9.90 1,591 15,758 Total 5,246 37,026 Overturning Ratio 3.78 ASSUMPTIONS AND CRITERIA USED 1. References used include Design Manual for Segmental Retaining Walls, 2nd Edition, and Segmental Retaining Walls – Seismic Design Manual, 1st Edition, both by NCMA. 2. Blocks are all same size and uniform offsets (batter) for full wall height.3. Coulomb earth pressure theory used for earth pressures and failure plane angle.4. Refer to geotechnical report for backfill material, compaction, and other design data and recommendations.5. Cap blocks if used are above the retained height and are neglected in this design.6. Geogrid LTDS and connection values for block vendors obtained from ICC Evaluation Service (ES Legacy Reports) or as provided by vendors. Since these may change or be updated, verification of values is recommended. 7. Block sizes obtained from vendors’ literature and may vary with locality. 8. Geogrid layers are equally spaced vertically, all same length, and laid horizontally. 9. Average weight of block and cell infill assumed to be 120 pcf.10. See vendor web sites (on input screen) for more information and specifications.11. Design height is limited to 16 feet or 24 blocks, whichever is less. Contact vendor for higher designs or special conditions.12. Seismic design is per Seismic Design Manual cited above. Also see Methodology/Seismic Design in User’s Manual. 13. Vendor specifications or project specifications, whichever is most restrictive, to be followed for construction procedures. 14. Add notes and details for proper drainage. 15. See User’s Manual Design Example #10 for methodology and sample verification calculations. 16. Final design responsibility is with the project Engineer-of-Record. Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Thumbnail Criteria Wall height (retained height), ft 16.00 Backfill slope 4:1 Backfill angle 14.0 Embedment 1.0 Soil data External Soil, Phi_e 42 External soil density (In situ), pcf 130 Internal Soil, Phi_i 34 Internal soil density, pcf 130 Wall Soil Friction Angle 23 K_a(Horiz) 0.23 K_AE(Horiz) 0.41 If seismic included the min. OTM and sliding ratios may be 1.1 per IBC '09, 1807.2.3. Stability Overturning ratio 3.92 Sliding ratio 3.93 Overturning moment, ft-lbs 56,404 Resisting moment, ft-lbs 221224 Total lateral/sliding force, lbs 6,945 Sliding Resistance, ft 27,301.97 Total vertical force, lbs 30,322 Base length, ft 13.56 Eccentricity on base, ft 1.34 Effective base length, ft 10.87 Soil bearing pressure, psf 2,789.15 Allowable soil bearing, psf 0.00 Soil Bearing Ratio 0.00 Loading Dead load, psf 0 Live load, psf 0 Seismic Design Kh 0.05 Segmental block data Vendor selection Keystone Retaining Wall Systems Vendor web address www.keystonewalls.com Block selection type Standard 18" Block height, in 8.00 Block depth, in 18.00 Offset per block, in 1.00 Batter angle 7.13 Wall weight, psf 180.00 Hinge height, ft 12.00 Geogrid material Vendor Selection Synteen Vendor web address www.synteen.com Geogrid type Synteen SF 110 LTDS 5652.52 Factor of safety 1.50 LTADS 3768.35 Peak connection equation 3885 + 0.2N Peak connection maximum 5456 Serviceability connection equation 1534 + 0.11N Serviceability connection maximum 2427Wall Analysis Table: Block Layer Height above base Tension Embed Vert S. F. Seismic Le NServPeak Connection StaticDecInFt 24 0" 16.0016' 20 7 4" 13.33 185 1586.813'2654.0 2.94 480 631 1.94 17 6 4" 11.33 277 1626.411'2702.0 2.03 840 485 2.13 14 5 4" 9.33 396 1666.0 9'2750.0 1.78 1,200 429 2.02 11 4 4" 7.33 515 1705.6 7'2798.0 1.65 1,560 373 1.92 8 3 4" 5.33 633 1745.2 5'2846.0 1.56 1,920 317 1.84 5 2 4" 3.33 752 1784.8 3'2894.0 1.51 2,280 261 1.76 2 1 4" 1.33 726 1824.4 1'2942.0 1.39 2,640 171 2.04 Base 0" 0.00 0'2,880 Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Summary: Resisting / Overturning Resisting Moments Distance, ft Moment, ft-lbs Wall 1.75 2,880 5,040 Reinf. earth 7.53 188,889 25,085 11.58Sloped 27,296 2,357 9.53 0Dead load 0 0 9.53Live load 0 221,224 3,982 6.34 25,227 0 9.50 0 Total 30,322 Item Force, lbs Overturning Moments 0 9.50 0 Item Force, lbs Distance, ft Moment, ft-lbs 144 8.00 1,152 Earth 676 8.00 5,408 Surcharge, DL 34 566 16.53 Surcharge, LL Seismic, Wall Seismic, Reinf. Seismic, Sloped soil Seismic, Exterior 11.40 2,109 24,051 Total 6,945 56,404 Overturning Ratio 3.92 ASSUMPTIONS AND CRITERIA USED 1. References used include Design Manual for Segmental Retaining Walls, 2nd Edition, and Segmental Retaining Walls – Seismic Design Manual, 1st Edition, both by NCMA. 2. Blocks are all same size and uniform offsets (batter) for full wall height.3. Coulomb earth pressure theory used for earth pressures and failure plane angle.4. Refer to geotechnical report for backfill material, compaction, and other design data and recommendations.5. Cap blocks if used are above the retained height and are neglected in this design.6. Geogrid LTDS and connection values for block vendors obtained from ICC Evaluation Service (ES Legacy Reports) or as provided by vendors. Since these may change or be updated, verification of values is recommended. 7. Block sizes obtained from vendors’ literature and may vary with locality. 8. Geogrid layers are equally spaced vertically, all same length, and laid horizontally. 9. Average weight of block and cell infill assumed to be 120 pcf.10. See vendor web sites (on input screen) for more information and specifications.11. Design height is limited to 16 feet or 24 blocks, whichever is less. Contact vendor for higher designs or special conditions.12. Seismic design is per Seismic Design Manual cited above. Also see Methodology/Seismic Design in User’s Manual. 13. Vendor specifications or project specifications, whichever is most restrictive, to be followed for construction procedures. 14. Add notes and details for proper drainage. 15. See User’s Manual Design Example #10 for methodology and sample verification calculations. 16. Final design responsibility is with the project Engineer-of-Record. Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Thumbnail Criteria Wall height (retained height), ft 18.00 Backfill slope 4:1 Backfill angle 14.0 Embedment 1.0 Soil data External Soil, Phi_e 42 External soil density (In situ), pcf 130 Internal Soil, Phi_i 34 Internal soil density, pcf 130 Wall Soil Friction Angle 23 K_a(Horiz) 0.23 K_AE(Horiz) 0.41 If seismic included the min. OTM and sliding ratios may be 1.1 per IBC '09, 1807.2.3. Stability Overturning ratio 3.82 Sliding ratio 3.89 Overturning moment, ft-lbs 80,349 Resisting moment, ft-lbs 307051 Total lateral/sliding force, lbs 8,792 Sliding Resistance, ft 34,170.62 Total vertical force, lbs 37,950 Base length, ft 15.06 Eccentricity on base, ft 1.56 Effective base length, ft 11.95 Soil bearing pressure, psf 3,176.48 Allowable soil bearing, psf 0.00 Soil Bearing Ratio 0.00 Loading Dead load, psf 0 Live load, psf 0 Seismic Design Kh 0.05 Segmental block data Vendor selection Keystone Retaining Wall Systems Vendor web address www.keystonewalls.com Block selection type Standard 18" Block height, in 8.00 Block depth, in 18.00 Offset per block, in 1.00 Batter angle 7.13 Wall weight, psf 180.00 Hinge height, ft 12.00 Geogrid material Vendor Selection Synteen Vendor web address www.synteen.com Geogrid type Synteen SF 110 LTDS 5652.52 Factor of safety 1.50 LTADS 3768.35 Peak connection equation 3885 + 0.2N Peak connection maximum 5456 Serviceability connection equation 1534 + 0.11N Serviceability connection maximum 2427Wall Analysis Table: Block Layer Height above base Tension Embed Vert S. F. Seismic Le NServPeak Connection StaticDecInFt 27 0" 18.0018' 23 8 4" 15.33 185 1586.815'2654.0 3.15 480 718 1.76 20 7 4" 13.33 277 1626.413'2702.0 2.14 840 560 1.94 17 6 4" 11.33 396 1666.011'2750.0 1.85 1,200 504 1.85 14 5 4" 9.33 515 1705.6 9'2798.0 1.70 1,560 448 1.77 11 4 4" 7.33 633 1745.2 7'2846.0 1.61 1,920 392 1.70 8 3 4" 5.33 752 1784.8 5'2894.0 1.54 2,280 336 1.64 5 2 4" 3.33 871 1824.4 3'2942.0 1.50 2,640 280 1.59 2 1 4" 1.33 825 1864.0 1'2990.0 1.38 3,000 186 1.84 Base 0" 0.00 0'3,240 Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMARP9.27 Summary: Resisting / Overturning Resisting Moments Distance, ft Moment, ft-lbs Wall 1.87 3,240 6,075 Reinf. earth 8.28 262,728 31,730 12.84Sloped 38,248 2,980 10.53 0Dead load 0 0 10.53Live load 0 307,051 5,039 7.13 35,910 0 10.69 0 Total 37,950 Item Force, lbs Overturning Moments 0 10.69 0 Item Force, lbs Distance, ft Moment, ft-lbs 162 9.00 1,458 Earth 878 9.00 7,898 Surcharge, DL 46 849 18.62 Surcharge, LL Seismic, Wall Seismic, Reinf. Seismic, Sloped soil Seismic, Exterior 12.83 2,669 34,235 Total 8,792 80,349 Overturning Ratio 3.82 ASSUMPTIONS AND CRITERIA USED 1. References used include Design Manual for Segmental Retaining Walls, 2nd Edition, and Segmental Retaining Walls – Seismic Design Manual, 1st Edition, both by NCMA. 2. Blocks are all same size and uniform offsets (batter) for full wall height.3. Coulomb earth pressure theory used for earth pressures and failure plane angle.4. Refer to geotechnical report for backfill material, compaction, and other design data and recommendations.5. Cap blocks if used are above the retained height and are neglected in this design.6. Geogrid LTDS and connection values for block vendors obtained from ICC Evaluation Service (ES Legacy Reports) or as provided by vendors. Since these may change or be updated, verification of values is recommended. 7. Block sizes obtained from vendors’ literature and may vary with locality. 8. Geogrid layers are equally spaced vertically, all same length, and laid horizontally. 9. Average weight of block and cell infill assumed to be 120 pcf.10. See vendor web sites (on input screen) for more information and specifications.11. Design height is limited to 16 feet or 24 blocks, whichever is less. Contact vendor for higher designs or special conditions.12. Seismic design is per Seismic Design Manual cited above. Also see Methodology/Seismic Design in User’s Manual. 13. Vendor specifications or project specifications, whichever is most restrictive, to be followed for construction procedures. 14. Add notes and details for proper drainage. 15. See User’s Manual Design Example #10 for methodology and sample verification calculations. 16. Final design responsibility is with the project Engineer-of-Record. Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Thumbnail Criteria Wall height (retained height), ft 20.00 Backfill slope 4:1 Backfill angle 14.0 Embedment 1.0 Soil data External Soil, Phi_e 42 External soil density (In situ), pcf 130 Internal Soil, Phi_i 34 Internal soil density, pcf 130 Wall Soil Friction Angle 23 K_a(Horiz) 0.23 K_AE(Horiz) 0.41 If seismic included the min. OTM and sliding ratios may be 1.1 per IBC '09, 1807.2.3. Stability Overturning ratio 3.93 Sliding ratio 3.94 Overturning moment, ft-lbs 111785 Resisting moment, ft-lbs 439233 Total lateral/sliding force, lbs 10,957 Sliding Resistance, ft 43,201.18 Total vertical force, lbs 47,980 Base length, ft 17.06 Eccentricity on base, ft 1.71 Effective base length, ft 13.65 Soil bearing pressure, psf 3,515.15 Allowable soil bearing, psf 0.00 Soil Bearing Ratio 0.00 Loading Dead load, psf 0 Live load, psf 0 Seismic Design Kh 0.05 Segmental block data Vendor selection Keystone Retaining Wall Systems Vendor web address www.keystonewalls.com Block selection type Standard 18" Block height, in 8.00 Block depth, in 18.00 Offset per block, in 1.00 Batter angle 7.13 Wall weight, psf 180.00 Hinge height, ft 12.00 Geogrid material Vendor Selection Synteen Vendor web address www.synteen.com Geogrid type Synteen SF 110 LTDS 5652.52 Factor of safety 1.50 LTADS 3768.35 Peak connection equation 3885 + 0.2N Peak connection maximum 5456 Serviceability connection equation 1534 + 0.11N Serviceability connection maximum 2427Wall Analysis Table: Block Layer Height above base Tension Embed Vert S. F. Seismic Le NServPeak Connection StaticDecInFt 30 0" 20.0020' 28 14 8" 18.67 53 1560.418'2622.0 3.56 240 485 2.90 26 13 4" 17.33 106 1586.817'2654.0 2.34 480 460 2.80 24 12 0" 16.00 158 1613.216'2686.0 1.94 720 435 2.72 22 11 8" 14.67 211 1639.614'2718.0 1.74 960 411 2.64 20 10 4" 13.33 264 1666.013'2750.0 1.62 1,200 386 2.57 18 9 0" 12.00 317 1692.412'2782.0 1.54 1,440 361 2.50 16 8 8" 10.67 369 1718.810'2814.0 1.48 1,680 336 2.44 14 7 4" 9.33 422 1745.2 9'2846.0 1.44 1,920 311 2.38 12 6 0" 8.00 475 1771.6 8'2878.0 1.40 2,160 286 2.33 10 5 8" 6.67 528 1798.0 6'2910.0 1.37 2,400 261 2.28 Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 8 4 4" 5.33 581 1824.4 5'2942.0 1.35 2,640 236 2.23 6 3 0" 4.00 633 1850.8 4'2974.0 1.33 2,880 211 2.19 4 2 8" 2.67 686 1877.2 2'3006.0 1.32 3,120 186 2.15 2 1 4" 1.33 739 1903.6 1'3038.0 1.31 3,360 161 2.11 Base 0" 0.00 0'3,600 Summary: Resisting / Overturning Resisting Moments Distance, ft Moment, ft-lbs Wall 2.00 3,600 7,200 Reinf. earth 9.28 375,432 40,456 14.43Sloped 56,601 3,924 11.78 0Dead load 0 0 11.78Live load 0 439,233 6,285 7.96 50,028 0 11.94 0 Total 47,980 Item Force, lbs Overturning Moments 0 11.94 0 Item Force, lbs Distance, ft Moment, ft-lbs 180 10.00 1,800 Earth 1,105 10.00 11,050 Surcharge, DL 59 1,212 20.70 Surcharge, LL Seismic, Wall Seismic, Reinf. Seismic, Sloped soil Seismic, Exterior 14.33 3,329 47,695 Total 10,957 111,785 Overturning Ratio 3.93 ASSUMPTIONS AND CRITERIA USED 1. References used include Design Manual for Segmental Retaining Walls, 2nd Edition, and Segmental Retaining Walls – Seismic Design Manual, 1st Edition, both by NCMA.2. Blocks are all same size and uniform offsets (batter) for full wall height. 3. Coulomb earth pressure theory used for earth pressures and failure plane angle. 4. Refer to geotechnical report for backfill material, compaction, and other design data and recommendations. 5. Cap blocks if used are above the retained height and are neglected in this design.6. Geogrid LTDS and connection values for block vendors obtained from ICC Evaluation Service (ES Legacy Reports) or as provided by vendors. Since these may change or be updated, verification of values is recommended. 7. Block sizes obtained from vendors’ literature and may vary with locality.8. Geogrid layers are equally spaced vertically, all same length, and laid horizontally. 9. Average weight of block and cell infill assumed to be 120 pcf. 10. See vendor web sites (on input screen) for more information and specifications. 11. Design height is limited to 16 feet or 24 blocks, whichever is less. Contact vendor for higher designs or special conditions.12. Seismic design is per Seismic Design Manual cited above. Also see Methodology/Seismic Design in User’s Manual.13. Vendor specifications or project specifications, whichever is most restrictive, to be followed for construction procedures.14. Add notes and details for proper drainage.15. See User’s Manual Design Example #10 for methodology and sample verification calculations. 16. Final design responsibility is with the project Engineer-of-Record. Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 Thumbnail Criteria Wall height (retained height), ft 22.00 Backfill slope 4:1 Backfill angle 14.0 Embedment 1.0 Soil data External Soil, Phi_e 42 External soil density (In situ), pcf 130 Internal Soil, Phi_i 34 Internal soil density, pcf 130 Wall Soil Friction Angle 23 K_a(Horiz) 0.23 K_AE(Horiz) 0.41 If seismic included the min. OTM and sliding ratios may be 1.1 per IBC '09, 1807.2.3. Stability Overturning ratio 3.51 Sliding ratio 3.74 Overturning moment, ft-lbs 144985 Resisting moment, ft-lbs 508886 Total lateral/sliding force, lbs 13,030 Sliding Resistance, ft 48,686.28 Total vertical force, lbs 54,072 Base length, ft 17.56 Eccentricity on base, ft 2.05 Effective base length, ft 13.46 Soil bearing pressure, psf 4,017.22 Allowable soil bearing, psf 0.00 Soil Bearing Ratio 0.00 Loading Dead load, psf 0 Live load, psf 0 Seismic Design Kh 0.05 Segmental block data Vendor selection Keystone Retaining Wall Systems Vendor web address www.keystonewalls.com Block selection type Standard 18" Block height, in 8.00 Block depth, in 18.00 Offset per block, in 1.00 Batter angle 7.13 Wall weight, psf 180.00 Hinge height, ft 12.00 Geogrid material Vendor Selection Synteen Vendor web address www.synteen.com Geogrid type Synteen SF 110 LTDS 5652.52 Factor of safety 1.50 LTADS 3768.35 Peak connection equation 3885 + 0.2N Peak connection maximum 5456 Serviceability connection equation 1534 + 0.11N Serviceability connection maximum 2427Wall Analysis Table: Block Layer Height above base Tension Embed Vert S. F. Seismic Le NServPeak Connection StaticDecInFt 33 0" 22.0022' 30 15 0" 20.00 99 1573.620'2638.0 3.38 360 653 2.09 28 14 8" 18.67 132 1600.018'2670.0 2.20 600 498 2.54 26 13 4" 17.33 185 1626.417'2702.0 1.89 840 473 2.47 24 12 0" 16.00 237 1652.816'2734.0 1.72 1,080 448 2.41 22 11 8" 14.67 290 1679.214'2766.0 1.62 1,320 423 2.35 20 10 4" 13.33 343 1705.613'2798.0 1.54 1,560 398 2.30 18 9 0" 12.00 396 1732.012'2830.0 1.49 1,800 373 2.25 16 8 8" 10.67 449 1758.410'2862.0 1.45 2,040 348 2.21 14 7 4" 9.33 501 1784.8 9'2894.0 1.41 2,280 323 2.16 12 6 0" 8.00 554 1811.2 8'2926.0 1.39 2,520 298 2.12 Phil Haberman Geotechnical/Geologic Consultant MSE Wall Design Title :...New...Page: ______ Job #:...New...Dsgnr: Date:FEB 5,2018 Description.... This Wall in File: c:\users\phaberman\desktop\12footer.rp5 Retain Pro 9 © 1989 - 2011 Ver: 9.27 8171 Segmental Retaining Wall Design with Geogrids Code: NCMA RP9.27 10 5 8" 6.67 607 1837.6 6'2958.0 1.36 2,760 274 2.09 8 4 4" 5.33 660 1864.0 5'2990.0 1.35 3,000 249 2.05 6 3 0" 4.00 712 1890.4 4'3022.0 1.33 3,240 224 2.02 4 2 8" 2.67 765 1916.8 2'3054.0 1.32 3,480 199 1.99 2 1 4" 1.33 818 1943.2 1'3086.0 1.30 3,720 174 1.96 Base 0" 0.00 0'3,960 Summary: Resisting / Overturning Resisting Moments Distance, ft Moment, ft-lbs Wall 2.12 3,960 8,415 Reinf. earth 9.53 437,728 45,932 15.01Sloped 62,743 4,180 12.28 0Dead load 0 0 12.28Live load 0 508,886 7,453 8.67 64,606 0 13.00 0 Total 54,072 Item Force, lbs Overturning Moments 0 13.00 0 Item Force, lbs Distance, ft Moment, ft-lbs 198 11.00 2,178 Earth 1,359 11.00 14,944 Surcharge, DL 73 1,666 22.78 Surcharge, LL Seismic, Wall Seismic, Reinf. Seismic, Sloped soil Seismic, Exterior 15.60 3,948 61,592 Total 13,030 144,985 Overturning Ratio 3.51 ASSUMPTIONS AND CRITERIA USED 1. References used include Design Manual for Segmental Retaining Walls, 2nd Edition, and Segmental Retaining Walls – Seismic Design Manual, 1st Edition, both by NCMA.2. Blocks are all same size and uniform offsets (batter) for full wall height.3. Coulomb earth pressure theory used for earth pressures and failure plane angle.4. Refer to geotechnical report for backfill material, compaction, and other design data and recommendations. 5. Cap blocks if used are above the retained height and are neglected in this design. 6. Geogrid LTDS and connection values for block vendors obtained from ICC Evaluation Service (ES Legacy Reports) or as provided by vendors. Since these may change or be updated, verification of values is recommended. 7. Block sizes obtained from vendors’ literature and may vary with locality.8. Geogrid layers are equally spaced vertically, all same length, and laid horizontally.9. Average weight of block and cell infill assumed to be 120 pcf.10. See vendor web sites (on input screen) for more information and specifications. 11. Design height is limited to 16 feet or 24 blocks, whichever is less. Contact vendor for higher designs or special conditions. 12. Seismic design is per Seismic Design Manual cited above. Also see Methodology/Seismic Design in User’s Manual. 13. Vendor specifications or project specifications, whichever is most restrictive, to be followed for construction procedures.14. Add notes and details for proper drainage.15. See User’s Manual Design Example #10 for methodology and sample verification calculations.16. Final design responsibility is with the project Engineer-of-Record. Cobalt Geosciences P.O. Box 82243 Kenmore, Washington 98028 (206) 331-1097 February 26, 2018 Mr. Hakam Singh hakamseattle@gmail.com RE: Rockery Wall Recommendations Proposed Residential Plat Duvall Avenue NE and SE 95th Way Renton, Washington Dear Mr. Singh, In accordance with your authorization, Cobalt Geosciences, LLC (Cobalt) has prepared retaining wall recommendations for above referenced site. The proposed construction includes one or more rockery walls, up to 8 feet in height, located along the west property line. Rockeries Rockery walls are not considered as engineered gravity retaining walls mainly because the structure is not an integral as the rocks are just siting and they are not structurally connected to each other. They generally function as erosion protection for the materials they face that are themselves stable, which should be dense to very dense soils with adequate fines, preferably glacially consolidated materials in the region. Based on our observations at the site, the underlying materials appear to consist of relatively dense glacial till. All rockeries should be constructed per the Associated Rockery Contractors (ARC) guidelines(http://www.ceogeo.org/schedule/09244404pm_Current%202013%20ARC%20R ockery%20Construction%20Guidelines.pdf) with periodic monitoring of the keyway excavation, drainage, rock placement, backfill, and excavation work by the geotechnical engineer. Recommendations Our rockery design recommendations refer to various rock sizes. The Washington State Department of Transportation (WSDOT) uses the following table when referring to larger size rocks and boulders: February 26, 2018 Page 2 of 5 Rockery Recommendations Rock Size Rock Weight Ave. Dimensions Half Man 25 - 50lbs 6” - 12" One Man 50 - 200lbs 12" - 18" Two Man 200 - 700lbs 18" - 28" Three Man 700 - 2,000lbs 28" - 36" Four Man 2,000 - 4,000lbs 36" - 48" Five Man 4,000 - 6,000lbs 48" - 54" Six Man 6,000 - 8,000lbs 54" - 60" Design Parameters The following soil parameters were used in rockery design calculations: Soil Type Friction Angle Cohesion Unit Weight Retained Soils (Glacial Till) 36 degrees 0 psf 120 pcf Foundation Soils (Glacial Till) 36 degrees 0 psf 120 pcf psf = pounds per square foot pcf = pounds per cubic foot A unit weight of 155 pcf was used for large rocks. The designs also utilized an assumed wall batter of 6V:1H (Vertical to Horizontal) and variable back slope angles up to a maximum of 2H:1 (Horizontal to Vertical). The rockery walls should consist of sound rock in decreasing size from bottom to top. We recommend using 3 and 4-man sized rock for the base, decreasing to ½ to 1-man sized rock at the top. Rockery backfill should consist of 2-4 quarry rock placed at least 1.5 feet behind the wall. A 4-inch diameter, Schedule 40 perforated PVC pipe should be placed at the base of the rockery extending from behind the wall and tightlined into an appropriate stormwater system. A representative of the geotechnical firm should be on site during all wall construction activities, including keyway excavation work, new fill placement/compaction, drainage placement, rock placement, and finish grading. The following tables indicate recommended minimum rock sizes for use in rockery wall construction for various wall heights and back slope angles. All heights shown in the tables are for the exposed wall heights, not total height. All walls over 4 feet in exposed height should have a minimum 12-inch embedment into the native soils. February 26, 2018 Page 3 of 5 Rockery Recommendations 4 Feet Tall Rockery Wall Back Slope Angle Base Rock Size (Min. in Feet) Top Rock Size (Min. in Feet) Level to 4H:1V 2 1.5 4H:1V to 2.5H:1V 2.5 1.5 2H:1V 2.5 2 5 Feet Tall Rockery Wall Back Slope Angle Base Rock Size (Min. in Feet) Top Rock Size (Min. in Feet) Level to 4H:1V 2.5 1.5 4H:1V to 2.5H:1V 2.5 2 2H:1V 3 2 6 Feet Tall Rockery Wall Back Slope Angle Base Rock Size (Min. in Feet) Top Rock Size (Min. in Feet) Level to 4H:1V 3 2 4H:1V to 2.5H:1V 3 2.5 2H:1V 3.5 2.5 February 26, 2018 Page 4 of 5 Rockery Recommendations 7 Feet Tall Rockery Wall Back Slope Angle Base Rock Size (Min. in Feet) Top Rock Size (Min. in Feet) Level to 4H:1V 3.5 2 4H:1V to 2.5H:1V 3.5 2.5 2H:1V 4 2.5 8 Feet Tall Rockery Wall Back Slope Angle Base Rock Size (Min. in Feet) Top Rock Size (Min. in Feet) Level to 4H:1V 3.5 2.5 4H:1V to 2.5H:1V 3.5 3 2H:1V 4 3 Limitations Earthwork construction is characterized by the presence of a calculated risk that soil and groundwater conditions have been fully revealed by the original evaluation. This risk is derived from the practical necessity of basing interpretations and design conclusions on limited observation of the earth. The recommendations made in this report are based on the assumption that soil conditions consist of glacially consolidated till or outwash materials. If any variations or undesirable conditions are encountered during construction, Cobalt Geosciences should be notified so that supplemental/alternative recommendations can be made. The conclusions of this report are based on the limited information provided regarding the proposed construction. If the proposed construction is relocated or redesigned, the conclusions in this report may not be valid. Cobalt Geosciences should be notified of any changes so that the recommendations can be reviewed and re-evaluated. Cobalt Geosciences should monitor all aspects of wall construction. February 26, 2018 Page 5 of 5 Rockery Recommendations This report was prepared for the exclusive use of Hakam Singh and his appointed consultants. Any use of this report or the material contained herein by third parties, or for other than the intended purpose, should first be approved in writing by Cobalt Geosciences. The information presented herein is based upon professional interpretation utilizing standard practices and a degree of conservatism deemed proper for this project. We emphasize that this report is valid for this project as outlined above, and should not be used for any other site. Sincerely, Cobalt Geosciences, LLC Phil Haberman, PE, LG, LEG Principal PH/sc