HomeMy WebLinkAboutTED4001782.59A. GENERAL
B.
C.
The amount of concrete required to anchor horizontal bends, tees,
and dead ends depends on the strength of the soil. The methods of
placing concrete to keep the joint accessible is shown in Figure 1.
The area in square feet of concrete wnich must bear against the side
of the trench is found by dividing the thrust in pounds shown in
Table 1 by the safe bearing load of the soil as shown in 'able 2.
CRITERIA
1. The sizing procedure is for horizontal or downward thrust only.
2. Meight of :he thrust block must be equal to or less than 1/2
the depth from the around surface to the block base.
3. The thrust block bearing face is approximately rectangular.
4. The concrete blocking shall be as per APWA Specification 74-2.14.
SYMBOLS
d - Outside Diameter of Pipe in Feet
T - Thrust in Pounds at the Fitting (Table 1)
SBL - Safe bearing Load in Pounds/Sq. Ft. (Table 2)
h - Depth of Trench in Feet
W - Width of Trench in Feet
A - Area of Concrete which must bear Against the Side of the Trench
,n Sq. Ft.
Hm - Maximum Height of the Thrust Block in Feet
Dc - Depth of the Concrete Thrust Block to Bearing Surface in Feet
Lm - Maximum Length of the Thrust Block in Feet
GROUND SURFACE
T
BLOCK BASE
D. CALCULATION EQUATIONS
f Dc I
1
W
Thrust (in Pounds': T
1. Area of Concrete (A) =Safe Searing Load kin Pounas/Sq. Ft.7 SBL
2. Maximum Height of Thrust B1oGk (MR,) a Depth of Trench in Feet h2 - 'f
(Width of Trench in Feet)-ioutside
3. Depth of Concrete Thrust Block Diameter of pipe 1n Feet) W-d2 --�-
4, Maximum Length of Thrust Block (L..) ' Area of Concrete M. A
Maximum Height r?r,
5. Required Amount of Concrete (Cu. Yd.1-I.Height x Deoth x Length) x 0.03704
-(Hm x Lm x Dc) x 0.03704
E. EXAMPLE
i
I. Problem: Calcuiation of the amount of concrete required to block
a 9y 0 bend in an 8" C. 1. water main; the normal operating pressure
in the pipe will be 65 psi and the soil condition in the area indi-
cates sand and gravel.
2. Soiution:
Maximum testing pressure (See Table 1) - 300 psi
Outside diameter of 8" pipe - 9.05 in,. - 9.05/'.2 - 0.75 ft•
Go to Table is The testing pressure of 300 psi, we see that
tfre thrust on a 90° bend is 21,360 pounds.
Go to Table 2: Table 2 gives the safe bearing load for sand
and gravel: 3,000 lbs./sq. ft.
Go to Figure is Figure i indicates the position of the concrete
for blocking the 90° bend.
Go to the specifications of the project and find depth of trench
(h) - 4 Beet
Width of trench (W) - 3 feet
With the above assembled information, we proceed to the final
ca I Cu I at I ons:
Area of Concrete (A) - ?gust 21 360
a e Bearing Load j pp = 7'12 sq. ft.
Depth of Trench h 4.
maximum Height of Thrust Block (Mm) - �-- Z ---- - ,f - 2.0 f t .
Depth of Concrete Thrust Block (DC)
Width of Trench in Feet (W) - Outside Diameter of Pipe (d)
• 2
0.75 • 1.13 ft.
2
Maximum Length of Thrust Block (Lm) - Area of Concrete
Meigrtt or Concrete
;;W- 2. a 3,56 ft.
,
Required Mwunt of Concrete -(Height x Depth x Length)x O.C3704
-(►m x Lm x Dc) x 0.03704
-(2.0 x 3.56 x 1.13) x 0.03704
- 0.30 cu . yd .
DRAWN
CHECKED
PROJ. ENGR.
DIST. ADM.
b. 7,P - -oJeo
H-E DOT FORM 221-011
Revised 6 /80
1 - �
1 ° -,
' 0
CAP
TEE
1t L* BEND
FIGURE I
222 BEND
45° BEND
• 5, 1.
i
.� b
T
1
90• BEND
NOTE: FOR CONVEX VERTICAL BENDS BLOCKING,
SEE APWA STANDARD PLAN NO. 73.
TABLE I
SIZE
PRESSURE
PSI
THRUS' AT FITTINGS i N POUNDS
I TEES
DEAD ENDS
9G°
BEND
45° 22-1/2"
BEND BEND
11-1/4'
SEND
3"
300
2,120
j 3,000
1,630
830
43C
4"
300
3,780
5,370
2,910
1,470
( 750
6"
300
8,500
12,000
6,510
3,320
.1 1,700
811
300
15,100
21,360
11 „50
5.880
3,020
104,
275
21,620
30,570
16,540
I 8,430
4.330
12"
250
33,930
I 48,000
25,950
13,260
6,780
1411
25O
46,200
65,370
35,340
18,030
9,240
16"
225
45,250
64,000 34,620
17,650
9,050
18"
200
50,900
72,000
38,940
99,860
10,18C
20"
200
62,840
88,900
48,080
24,520
12,560
200
90,480
127,980
69,200
35,320 1 18,100
E4"
200 ,
141,370
199.960 P
108,190 1
55,140
28,280
36"
200 1
203,580
287,950
155,740
79.400 40,720
TABLE 2
Safe Bearing Loads in Lb./So. Ft
The safe bearing loads given in the following taole are for
horizontal thrusts when the depth of cover over the pipe exceeds
2 feet.
SAFE BEARING'LOAD
SOIL Lb. per Sq. Ft.
*Muck, peat, etc. 0
Soft Clay 1,000
Sand 2,000
Sand and Gravel 3,000
Sand and Gravel Cemented with Clay 4,000
Hard Shale 10,030
*In muck or peat, all thrusts shall be restrained by piles or tie
rods to solid foundations or 5y removal of muck or peat and
replacement with oallast of sufficient stability to resist
thrusts.
REND N TOTAL
STATE FED. AID PROJ. NO S"rvo T SHEET.'
BRM 12 2-8(2 )
10 WASH, .I- 405-,3(635)
,no %,111uoc'R
8�W1010 1
CONTRACT �.
DATE REVISION BY APP'D o?6, �?? I
TIE ROD SELECTION TABLE
REGION NO.
STATE
FEDERAL AID PROJECT NO.
SHEET NO.
10
WASH.
BRM - 1288 (2)
I-405-3(r�35)
SIZE
PRESSURE
PS1
FORCE IN POUNDS
NUMBER OF TIE RODS
7I
2 1 3 I 4 I
I
6 i 8 10 ! 12 ' 14 I 16 I 24
3"
300
2,120
3/8"
300
3,780
3/8"
611
300
8.500
5/8"
1 1/2"
1 1
3/8" 1
8"
300
15.100
j 3/4" 1 5/8" 1
1/2"
10'
275
21.620
1 3/4„ i
i
5/8„
1/2"
12"
250
33,930
I I
3/4'' I
5/8" i
14"
250
46,200
! ; i
j
3/4'' i
I
16"
225
45.250
I j
3/41, ; 5/8"
1811
200
50,900
; i
3/4" 5/81,
201,
200
62.840
;
13/4" 5/8,1 , 1
2411
200
90.480
3/4" I
30''
200
141,370
7/8"
1
36"
200
203,580
+ ,
j
; ; 1" 7/81i
i
NOTES:
1. STEEL FOR TIE RODS SHALL HAVE AN ULTIMATE STRENGTH OF 40,000 PSI
OR MORE.
2. TIE RODS SHALL HAVE NATIONAL -COURSE THREADS WITH AT LEAST TWO NUTS
AT THE END OR ONE SELF-LOCKING NUT.
3. STRENGT►+ OF SPECIAL DEVICES USED FOR TIE RODS ATTACHMENT SHALL BE
SUFFICIENT TO TRANSMIT THE rORCE TO THE PIPE.
4. TIE RODS SHALL BE GALVANIZED OR COATED WITH 2 COATS OF KO➢PERS
COMPANY INC. SITUMASTIC 300-M (16 MIL MINIMUM DRY THICKNESS).
5. STEEL ROD COUPLINGS (STELLAR CORPORATION OR EQUAL) SHALL BE USED
TO CONNECT T140 TIE RODS IN ORDER TG GET ADDITIONAL LENGTH.
TIE BOLT
STAR SUPPLY CORPORATION OR EQUAL
CAST ON LUGS
FIRE HYDRANT AND GATE VALVE
DIVISION OF HIGHWAYS
CIV2e 2 7, /983
.-,, � .,_ . "J
TIE BOLT
"DUC-LUG"
STELLAR CORPORATION OR EQUAL
"DUC - LUG"
TIE ROD ATTACHMENTS
AIM Washington State
Vr,f Department of Transportation
t1jw 1v(b
STAR SUPPLY CORPORATION,
STELLAR CORPORATION OR EQUAL
RETAINER CLAMP
H
O,r cisTE
Fss�O N AL
S.W. GRADY WAY
BRIDGE REPLACEMENT
WATER STANDARD DETAILS
SHEET
2B O F 63
7S2 iP Z SHEETS
SCAlvhlEo MA,.3 2 8 203J