HomeMy WebLinkAboutSummary of Bidder Inquiries No. 4Page 1 of 3
Summary of Bidders Inquiries No. 4
Lake Washington Loop Trail Project
Federal Aid Number: TAP-HLP-1070-008
Date: January 26, 2021
The responses to bidder inquiries, unless incorporated into a formal addendum to the contract,
are not part of the contract and are provided for the bidders’ convenience only. The responses
may be considered along with all other information furnished to pr ospective bidders for the
purpose of bidding on the project. The use of information provided in the responses to bidder
inquiries is not to be construed in any way as a waiver of the provisions nor excuse the contractor
from full compliance with the contract requirements. Bidders are cautioned that subsequent
responses or contract addenda may affect or vary a response previously given and any such
subsequent response or addenda should be taken into consideration when submitting a bid for
the project.
Bidder Inquiry No. 1
I write to you for clarifications regarding several inconsistencies and contradictions in the plans and
specifications for bid items 21 & 22 that need to be resolved prior to bid. For efficiency I would
prefer to discuss these conditions with you by phone so the questions can be correctly formed and
publicly addressed by any needed addendum.
Bid Item 21, Bridge Railing Pedestrian Retrofit 6-06. Neither the plans nor specifications identify
whether the retrofit panels need to be galvanized. The plans indicate the panels are to be field
painted. It is unclear whether powder coating the panels, which is historically more cost effective, is
acceptable. If the panels are to be galvanized for a “dual coating system” which has been our
experience on prior WSDOT projects, the painting or powder coating would require a “sweep
blasting” [sand blasting] to provide the needed surface profile for adhesion and this is not
something that would be effectively done in the field. Painting bare steel would also require this
treatment and so it would seem the project manual needs to address this issue. It would be most
practical and cost effective for the panels to be delivered to site fully coated and ready for
installation and the project manual needs to provide a specified coating system for the retrofit
railings.
RFI: Are the retrofit railing panels to be galvanized?
RFI: Are the retrofit railing panels to be coated prior to site delivery?
RFI: Are the retrofit panels to be powder coated or painted?
Bid Item 22, Pedestrian Railings Type S-B30. The plans call out for hot dipped galvanizing and the
specifications reference paint/powder coat of galvanized surfaces, 6-07.3[11] but to not specify it as
a requirement. This ambiguity leaves a compromised bidding criterion. The galvanized surfaces
need to be “swept blast” prior to paint/powder coating for adhesion as does bare steel a process
most effectively carried out in the paint/powder coater facility.
Page 2 of 3
RFI: Are the new Pedestrian Railings to be coated after galvanizing?
RFI: We intend to propose powder coating the new Pedestrian Railings. Is this acceptable?
It is our experience that unresolved ambiguities in the bidding documents lead to change orders and
costly liabilities for the owner of the plans and specifications and we always to seek to bring these to
their attention prior to bid.
City of Renton Response to Bidder Inquiry No. 1
Yes, bridge railing shall be galvanized in accordance with General Note 12 on Sheet B4.01. This
covers all bridge railing: “Bridge Railing Type Pedestrian Retrofit” (Bid Item 21) and “Bridge Railing
Type S-BP30” (Bid Item 22). General Note 12 on Sheet B4.01 has been revised to clarify. Please refer
to Addendum No. 2 for clarification.
Retrofit railing may be shop or field painted in accordance with General Note 14 on Sheet B4.01. If
powder coated, retrofit railing panels shall be coated prior to site delivery. General Note 14 on
Sheet B4.01 has been revised to clarify and add powder coating as an option. Please refer to
Addendum No. 2 for clarification.
Retrofit panels may be painted or powder coated. General Note 14 on Sheet B4.01 has been revised
to clarify and add powder coating as an option. Please refer to Addendum No. 2 for clarification.
Yes. Pedestrian railings are to be coated after galvanizing. On sheet B4.01, General Note 12 requires
galvanizing and General Note 14 requires painting. General Note 12 and 14 on Sheet B4.01 have
been revised to clarify and add powder coating as an option. Please refer to Addendum No. 2 for
clarification.
Yes. General Note 12 and 14 on Sheet B4.01 have been revised to clarify and add powder coating
the pedestrian railings as an option. Please refer to Addendum No. 2 for clarification.
Bidder Inquiry No. 2
Further examination of the referenced bid item shows a contradiction regarding the anchor bolting
of the Bridge Railing for item 22. Sheet B4.05 calls out either resin bolted anchors or anchor bolts
[wedge anchors]. Sheet B4.06, detail C calls out a minimum 6" embedment for resin bonded
anchors.
Special Provision Division 6, 6-02.3 provides an embedment charts showing a 3 1/2" embedment
minimum but also dictates anchors are to be installed per Standard Specification 6 -02.3[18]. When
SS 6-02.3[18] is examined it dictates core drilled holes 1" larger than the anchors and references the
grouting of the anchors to follow specification 9-20.3[2]. This grout specification is for a mortar
grout, not a resin based grout.
The above explanation describes both the inconsistency and a further constructability
issue. Normal installation procedure would be to place the bridge railing in place and drill the
concrete through the holes provided in the channel steel of the railing and then place the
Page 3 of 3
anchors. The hole in the steel will be +/- 7/16" for a 3/8" anchor- and one could not then core drill
a hole in the concrete 1" larger through that hole as required by SS 6-02.3[18]. Further if an epoxy
resin is used the hole should not be more than 1/16"-1/8" larger than the anchor to achieve
adhesion but further it would be necessary to place the resin into the drilled hole throug h the hole
in the channel steel of the bridge anchor and in doing so one would not be able to monitor or even
see the amount of epoxy in the anchor hole.
Past experience has demonstrated successful use of 3/8" wedge anchors with a 3 1/2" embedment
as a practical anchor for use with this size and style of bridge rail. The resolution of this
contradiction will have significant cost savings for this bid item.
RFI: Will a 3/8" wedge anchor with a 3 1/2" embedment to secure the bridge railing be acceptable.
City of Renton Response to Bidder Inquiry No. 2
No, resin bonded anchors are required. Resin bonded anchor information has been revised in the
Plans. Please refer to Addendum No. 2 for clarification.
Bidder Inquiry No. 3
The plans show that the new wire mesh panels will be bolted to the existing 1" pickets on the
pedestrian bridge rail. The existing rail is built from 1" solid square bar and the pickets are on
average 5" apart. how is one supposed to drill through the side of the pickets as you can not fit a
drill into a 5" space? is there an alternate method for attachment that has been authorized?
City of Renton Response to Bidder Inquiry No. 3
The hole and bolt sizes are revised on Sheet B4.04 to allow smaller tools to fit in the gap between
pickets. This will allow smaller tools to fit in the 5” gap between pickets to aid constructability .
Please refer to Addendum No. 2 for clarification.
Bidder Inquiry No. 4
On drawing # b4.03 in the typical section detail, it shows 1/4" x 3" plate on one side of the mesh at
the top and bottom but on the other side of the mesh it shows 1/2" x 3" plate at the top of the
panel. Is this accurate? It seems to me that it should be 1/4" not 1/2" unless there is some
engineered reason for it to be thicker than the rest of the frame.
City of Renton Response to Bidder Inquiry No. 4
The plate thickness on the side of the panel against the existing rail shall be ½” thick. The plate
thickness on the side of the panel away from the existing rail shall be ¼” thick. Please refer to
Addendum No. 2 for clarification.
End of Summary of Bidder Inquiries No. 4