Inquiries for Project 04-006054

CONTRACTOR'S INQUIRY RESPONSES

July 15, 2002

CONTRACT NO. 04-006054
MODIFY I/C & SOUTH APPROACH
County Route: CC-680-23.9/24.9

 

The responses to contractors' inquiries, unless incorporated into a formal addenda to the contract, are not a part of the contract and are provided for the contractor's convenience only. In some instances, the question and answer may represent a summary of the matters discussed rather than a word-for-word recitation. The responses may be considered along with all other information furnished to prospective bidders for the purpose of bidding on the project. The availability or use of information provided in the responses to contractors' inquiries is not to be construed in any way as a waiver of the provisions of section 2-1.03 of the Standard Specifications or any other provision of the contract, the plans, Standard Specifications or Special Provisions, nor to excuse the contractor from full compliance with those 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. Inquiries submitted within seventy-two (72 ) hours of the bid opening date might not be addressed.

The Caltrans District 4 Office is located at 111 Grand Avenue, Oakland, CA 94612. Send Contractor Inquiries via email to the Duty Senior at Duty_Senior_District04@dot.ca.gov. The mailing address is P.O. Box 23660, Oakland, CA 94623-0660. The Duty Senior's telephone number is (510) 286-5209 and the fax number is (510) 622-1805. All inquiries must include the contract number.

Total Number of Inquiries:38
Inquiry
No.
Inquiry/Response

1.0

The following reference Contract Plan sheet 353 for Mococo OH Bridge 28-0356R P/C P/S Bulb-Tee Girder reinforcement:

The stirrups are detailed as #22 comprised of three parts, U shaped web, U shaped bottom flange lower bar, bottom flange cap.

A. The U shaped web stirrup would have an out to out dimension for the vertical legs of 178mm using the min pin diameter. This is 8mm too wide (250mm web - 40mm - 40mm clr)

B. The other two components would have a min vert tail length of 178mm. The required tail length is 136mm. To obtain the required length, each stirrup would have to be bent with a 178mm tail then manually cut to 136mm. This would be very labor intensive and costly.

Possible solutions:

A. Modify the clearance requirements. Make the stirrup into two L shaped pieces.

B. Make a one piece inverted cap. Horiz leg at the bottom of the flange with a tail (355mm long) bent at a 29 deg angle to follow the fillet (similar to a standard TJ shaped cap). This tail would end at the vert leg of the stirrup to allow PT strand and post tension duct placement.

Bid it as you see it, unless otherwise an addendum is issued to change the plans.

2.0

The following reference Contract Plan sheet 353 for Mococo OH Bridge 28-0356R P/C P/S Bulb-Tee Girder reinforcement:

The top flange reinforcement, #13 at 300mm spacing. In order to bend the bar in the 100mm corner with the clearances shown, the pin diameter would have to be reduced to 25mm, instead of the required 50mm. There is a possibility of cracking the bar at the bend.

Is the stirrup size correct at #22?

Possible solutions:

Use a straight bar at the top of the top flange with a slightly bent bar (no tails) at the bottom of the top flange to follow the angle.

Bid it as you see it, unless otherwise an addendum is issued to change the plans.

3.0

I cannot locate Item #180 (Concrete Gutter Lining) on the plans. Where is it shown? The only concrete gutter that I can find is behind Retaining Wall #5 and that is covered under Item #183 (Concrete gutter).

See Retaining Wall #4 Plans (Plan Sheet #197).

4.0

Bid Item 84 - Shoring 400m covers "Shoring" on Drawing Q-4 (upper right).  How is "cutoff wall (steel sheet piling)" paid for?  See 3271 M2 on drawing Q-4.

Cutoff Wall (Steel Sheet Piling) is paid as a separate item, Item #114. The unit of measurement is square meter.

5.0

What is the specification for cutoff wall (steel sheet piling)?

Cutoff Wall (Steel Sheet Piling) specification is in the special provisions (page 207).

6.0

On Sheet #331, top continued bars in soffitt is not identified.

Bid it as you see it, unless otherwise an addendum is issued to change the plans.

7.0

Sheet 335 through 346 - call out for bars on plan views are not clear. Can you simplify so it can be properly estimated?

Bid it as you see it, unless otherwise an addendum is issued to change the plans.

8.0

Can the sheet pile material for Item Number 84 - Shoring, be completly removed (salvaged) when no longer required for shoring?

See Special Provisions, Section 10-1.43.

9.0

Is the sheet pile material for Item Number 84 - Shoring, subject to the Buy America requirements?

See Special Provisions, Section 5-1.075.

10.0

Can the sheet pile material for Item Number 114 - Cutoff Wall (Steel Sheet Pile), be completly removed (salvaged) when no longer required?

See Special Provisions, Section 10-1.58.

11.0

Is the sheet pile material for Number 114 - Cutoff Wall (Steel Sheet Pile), subject to the Buy America requirements?

See Special Provisions, Section 5-1.075

12.0

What is the intended difference between the two separate specifications for precast girder support and lifting plans (Section 10-1.61 of the Special Provisions)?

Bid it as you see it, unless otherwise an addendum is issued to change the plans.

13.0

Page 214 of the Special Provisions allows two options for splicing the precast girders ("at ground level or at the final elevation"). However, the construction joint called out for the inverted "T" bent cap covers the prestress blockouts for the simple span stressing. Can this construction joint be lowered to allow simple span stressing "at the final elevation"?

The construction joint location may be modified only if the bent cap is fully supported on falsework during construction. This falsework needs to remain until the deck has been placed and has reached full strength.

14.0

Section 13-1.02 railroad requirements requires the contractor to work sunday night under a 3 hour work period for construction near the railroad tracks.

Question: What distance and measured from where constitutes "near"?

See Addendum #2. Section 13 revised.

15.0

On the drawings sheet 333 of 430, indicates the layout of the NPS line which refers to note #3. Note #3 refers to the mechanical drawings which are not included in this plan set. The specifications refer to ARV's, valves, expansion assemblies, etc.

Question: Where are the mechanical drawings?

Bid it as you see it, unless otherwise an addendum is issued to change the plans.

16.0

The grades depicted on sheets #228 & 229 do not appear to represent the actual contours that exist today.

Question: Are these contours correct?

Bid it as you see it, unless otherwise an addendum is issued to change the plans.

Sheets #228 & 229 are electrical detail sheets.

17.0

Re: Section 5-1.22, Non hazardous and hazardous Material, General

Permits and Licences, The Engineer will assume generator status.

Its our understanding that as the generator the Engineer will be responsible for the material after it has been disposed of in accordance with the contract.

Yes.

18.0

Are there any known utilities in conflict with the water line connection to the existing 305 mm line?

No known utilities are in conflict.

19.0

The water line alignment will require trenching under existing above ground petroleum lines. Will trench compaction be required in this area?

Yes.

20.0

Sheet c-22 indicates that Column A of Bent 5 is hazardous at depths of 1-3 meters. Is the excavation for the water line considered hazardous?

Analytical results of samples collected with the expected excavation limits of the water line did not exceed the hazardous waste thresholds. Therefore, the water line excavation is considered non-hazardous.

21.0

RE: Bid Item No. 146

A) Sheet #331 - Top cont'd bars in soffit not identified.

B) Sheet 335 through 346 - Can you simplify so they can be properly estimated. Interpretation could amount to hundreds of thousands of dollars. (Note: Addendum 2 did not address this question).

Bid it as you see it, unless otherwise an addendum is issued to change the plans.

22.0

There are currently no cross sections available for the structures on page 123 (SC-34). Will cross sections be issued and/or are they available?

Cross sections are not available.

23.0

Item ref: 201-204, Concrete Barrier
Special Provision Ref: Table of Contents - 10-1.91, pg. 250.

After paragraphs N, additional paragraphs B & C appear.

The additional Paragraphs B & C appear to be superfluous.Should they be deleted by addendum?

Bid it as you see it, unless an addendum is issued to change the plans.

24.0

In addenda 2 the sign quantities sheet s-8 (182 of 430) shoew the quantities of both furnish and install sign structure (truss) as changed to 57,492 kg. The engineer's estimate for Addenda 2 has quantities of 40,402 kg for both items 151 (f) and 152 (s-f).

Which quantity is correct?

See Addendum #4. Items #151 and #152 of Engineer's Estimate were revised.

25.0

In Addenda 2, a sign foundation was added to retaining wall #2.

Please clarify as to where the metal portion of the sign foundation is paid.

Bid it as you see it, unless otherwise an addendum is issued to change the plans.

26.0

Item Ref: 151, 152, F&I Sign Structure
Plan Sheet ref: 182 of 430
Special Provisions ref: Section 10-1.74, pg. 242

Addendum #2 revised the Overhead Sign Quantities chart S-8, sheet #182 for Furnish and Install Sign Structure (Truss) from 40402 KG to 57492 KG. This is not reflected in Addendum #2 or #3 for Items #151 and 152. This is a very large change (42%) that must be absorbed in the Final Pay Items if not revised.

See Addendum #4. Items #151 and #152 of Engineer's Estimate were revised.

27.0

In regard to the above mentioned bid proposal, we have received the Notice to Contractors and Special Provisions on the project and I would like to know who are the bidders on this project?

You can get the current list of bidders for any advertised contract by inputting the contract no. on this webpage address(it's long so just highlight, copy and paste onto your browser)-
http://troe.dot.ca.gov/FMRes/FMPro?-db=plan%5fholders.fp5&-format=zSearchTxt.htm&-lay=web%5fsearch%5fview&-max=1&-token=100&-view

28.0

The Special Provisions refer to the keff (effective stiffness)"..as shown on the plans" but it is not shown on the plans. Please provide the Keff value. (Please note that the Keff has been defined by the Special Provisions to have a tolerance of +/- 15% so the Keff value should be (F/Dmax*1/1.15) so that the actual Keff value can exceed Keff design value by 15% without exceeding F. F is defined on the plans to be the seismic lateral force and the Special Provisions refer to that value as a maximum)

Bid it as you see it, unless an addendum is issued to change the plans.

29.0

Prototypes are required to be tested at the period of vibration as shown on the plans. The plans show a 1.7 second period. If it is the intention of Caltrans to have these bearing tested at the period of vibration (real-time) this test must be done in Caltrans funded test machine, the SRMD at the University of California at San Diego (UCSD). This is the only facility that can test at that velocity. On past Caltrans projects that required the bearings to be tested at UCSD the Special Provisions have specifically stated that the testing will be done at UCSD and it has been done at not cost to the manufacture. Please confirm that the seismic bearing must be tested at the period of vibration and if so required, conform that Caltrans will conduct this testing at the UCSD at no cost to the manufacture. Alternately, the Special Provisions can be changed to allow prototype testing at a velocity of 25mm/sec, which is consistent with the production testing requirements. This velocity of testing can be performed by the bearing manufacture, eliminating the need for testing at UCSD.

Bid it as you see it, unless an addendum is issued to change the plans.

30.0

The Special Provisions require testing at a sinusoidal peak velocity of 25mm/sec. This velocity is in the quasi-static rang where the measured properties do not measurably vary whether the testing speed is sinusoidal or constant velocity. Sinusoidal testing does add to the cost of testing bearings without changing the test results. Please change the requirement to allow for constant velocity testing.

Bid it as you see it, unless an addendum is issued to change the plans.

31.0

The maximum testing speed for the thermal testing is only 25mm/min which is slower than out test machine is capable of testing. Please adjust the test maximum speed to 100mm/min.

Bid it as you see it, unless an addendum is issued to change the plans.

32.0

The maximum thermal lateral force needs to be increased by a factor of 10. The current value appears to be based on Kp instead of Ke. (Note: The Fy is 347kN at 22mm so the thermal force at 23mm should be close to the Fy value. It is currently shown as 37kN)

Bid it as you see it, unless an addendum is issued to change the plans.

33.0

Addendum no, 2 the revised plans changed type h excavation to hazardous. Does item 64 Structure Excavation type H now mean hazardous?

See Addendum #4. Engineer's Estimate was revised for Item #64.

34.0

The typical cross sections show excavation and embankment on the west side of the CCNB line from 96+19.830 to 98+66.000. The stage construction plan sheet 98 Detail D-D shows this work from CCNB 95+40.000 to WR 7+22.772. The cross sections for this project do not show this excavation/embankment. Are the typical cross sections correct?

Yes, the typical cross sections are correct. Stage Construction Plan, Sheet 98, Section D-D shows only portion of the typical cross section work. In the following stages, the rest of the typical cross section work is to be completed. The roadway excavation includes excavation for Lightweight Embankment Material (Cellular Concrete).

35.0

How is the existing roadway removal within the new roadway section paid for?

For the new roadway section, existing roadway removal is paid as roadway excavation unless otherwise shown or stated.

36.0

Ref Specification 10-1.61 and Plan pages 332 & 333. Paragraph 3 under the subsection titled "TEMPORARY GIRDER SEGMENT SUPPORTS AND TEMPORARY LATERIAL BRACING" states "Temporary supports for precast prestressed spliced concrete bridge members shall be placed parrallel to the bents". Is this in conflict with the details and girder lengths shown on plan pages 332 & 333?

Bid it as you see it, unless an addendum is issued to change the plans.

37.0

Ref Pay Item 149 "SHOTCRETE". We are unable to find a specification section regarding this work.

Bid it as you see it, unless an addendum is issued to change the plans.

38.0

In Addendum No. 2 Page 2, Paragraph 5 states:

In the Special Provisions Section 10-1.40 "Light Weight Embankment Material (cellular concrete)," in the thirteenth paragraph the first and second sentences are deleted.

Please clarify what sentences this refers to.

In Addendum No. 2, the first and second sentences of the thirteenth paragraph of Section 10-1.40 were deleted. However, the second sentence was deleted inadvertently, so it was returned via Addendum No. 4. The thirteenth paragraph of Section 10-1.40 should read as follows:

"On Waterfront Road, an existing water valve shall be protected during excavation for and placement of lightweight embankment material (cellular concrete) as shown on the plans. Final adjustment to grade will be made by others."