Geotechnical Site Investigations for Underground Projects Volume 1 (1984) / Chapter Skim
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Appendix C: Data Collection and Compilation Procedures
Appendix C: Data Collection and Compilation Procedures
Pages 128-148
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From page 128... ...
The firm's project manager and his assistant were briefed by the subcommittee's senior consultant on the procedures to be followed and the terminology to be used. (Examples of completed data forms were available for two projects volunteered by the Washington Metropolitan Area Transit Authority.)
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From page 129... ...
As a final check on consistency, the completed data forms were reviewed and often revised by the senior consultant and by the subcontractor as a prelude to the next stage, the creation of a project abstract. In completing a data form to approximately 100 percent, an interviewer was expected to combine answers from the owner, the contractor, the 40 percent stage forms, and sometimes the volunteered data forms.
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From page 130... ...
• The emphasis on •changed conditions claims• as a yardstick for measuring construction problems and cost overruns had to be changed when it became apparent that many cost overruns are recorded as contract modifications, even when the initial request for payment is in the form of a claim or results in the initiation of litigation. A different method of tabulating the information was formulated, which is indicated by the following note appended to each data form: •cost overrun tabulations make repeated refer ences to claims, claimed conditions, differing 130
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From page 131... ...
Final costs could not be obtained for projects under construction or for completed projects with continuing litigation over changed conditions claims. • Mined tunnel costs are rarely tabulated separately by owners, either as estimated or bid, and therefore the cost had to be determined by selecting the proper tunnel bid items from the total project bid items.
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From page 132... ...
Deep shafts generally are built for purposes other than those typical of civil engineering and, as a result, procedures common to mined tunnel projects are not always common to deep shafts. For example, deep shafts may proceed through design and construction without performance of a comprehensive site investigation, and many deep shaft projects are acquired by contractors through a process of negotiation rather than bidding.
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From page 133... ...
DESCRIPTION OP DATA PORI The 15-page data form included in this section was the basic means of compiling and recording information on every project selected for study as a case history. Many of the questions and information items are selfexplanatory, but others may be subject to interpretations that differ from the subcommittee's intent.
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From page 134... ...
II.l. Total Underground Construction Costs: modified to refer to mined (or sunk, or raised, in the case of deep shafts)
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From page 135... ...
The terminology was carried over from the inter views and •as-built• reports and recorded in the data forms in order to avoid second-guessing original sources. Hence, there are probably some instances in which the forms refer to wet tunnel occurrences as running ground when flowing ground would be a better description.
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From page 136... ...
(Note: Contract also included 6 shafts, a tiebreaker station, and a pilot tunnel for a future pas senger station. Unless otherwise noted, data presented are for running tunnels only.)
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From page 137... ...
Underground Construction Timea Scheduled& 286 calendar days for mining and placing temporary support in running tunnels III.
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From page 138... ...
& Rock tunnel -- no particular water bearing layer noted. water tablea 70 to 103 ft above tunnel crown.
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From page 139... ...
• No predictions. Prebid predicted ainillum sustained inflow and pressure& NO pre dictions.
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From page 140... ...
If provided, describea Results of all field and lab testing on soil samples, rock cores, boreholes, and observation wells.
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From page 141... ...
(The contractor was required to submit for ap proval a graphic network diagram [schedule] indicating construction dates for various major features, which did include running tunnels estimated at 286 calendar days for mining.)
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From page 142... ...
a Details of temporary support strictly the responsibility of the contractor, with payment to be included in the overall contract unit price per ft for •single track tunnel.• 7. Construction Methods Specified• Tllla Option*
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From page 143... ...
This final lining omitted in the 653 ft long section where a future station was to be blasted out of the rock between the running tunnels and the pilot drift. (Applies to standard tunnel section, as noted in 7, above.)
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From page 144... ...
If Contractor Claill was Based on Differing Site Conditions, Please Describe the Claimed Condition and Bow it Allegedly Differeda The contractor encountered ground so bad that the mole became stuck and efforts to turn the cutterhead resulted in flows of mud and water into the tunnel, with some caving above the tunnel. The mole fought its way through 300 ft of this ground but a top heading, hand-mined •rescue• tunnel had to be driven from ahead to meet the machine; a similar top heading was driven for 650 ft in the adja cent tube.
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From page 145... ...
The precipitates also clog drainage slots, lines, and gratings, and probably any gravel filter blankets under the concrete inverts. They tend to form messy, slippery deposits that can be a hazard on the safety walks.
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From page 146... ...
The delay in the completion of the work arises from un foreseeable causes beyond the control and without the fault or negligence of the Contractor, including but not restricted to, acts of God, acta of the public enemy, acts of the Authority in its contractual capacity, acta of another contractor in the performance of a contract with the Authority, fires, floods, epidemics, quarantine restrictions, strikes, freight embar goes, unusually severe weather, or delays of subcontractors or suppliers at any tier arising from causes other than normal weather beyond the control and without the fault or negligence of both the Contractor and such subcontractors or suppliers; and (2) The Contractor, within 10 days from the beginning of any such delay (unless the Contracting Officer grants a further period of time before the date of final payment under the con tract)
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From page 147... ...
for any costs incurred more than 20 days before the Contractor shall have noti fied the Contracting Officer in writing of the act or failure to act involved (but this requirement shall not apply as to a claim resulting from a suspension order)
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From page 148... ...
only SO percent of the invoiced cost of materials or equipment delivered to the site but not incorporated in the construction up to the time the materials or equipment are actually incorporated in the work.
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