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<br />scope of work also assumes that geotechnical drilling will be permitted between the hours of 8 a.m. and
<br />Sp.rn.
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<br />Subtask 3.2.4: Laboratory Testing
<br />Complete the following laboratory tests on representative disturbed and "undisturbedll soil samples:
<br />Moisture Content, Unit Weight, Atterberg limits, Grain Size Distribution, Unconfined Compression,
<br />Direct Shear, Consolidation, and Soil Corrosivity,
<br />
<br />Subtask 3.2.5: Geotechnical Analysis and Report
<br />Geotechnical engineering analysis of the data gathered in Subtasks 3.2.1 through 3.2.4 with specific
<br />conclusions and recommendations to supplement design and construction of the following:
<br />
<br />1. General: Describe geologic and seismic setting, site history" and engineering properties (i.e.,
<br />composition and consistency) of soils encountered in test borings. Describe groundwater
<br />conditions. Describe geologic hazards such as liquefaction, fault rupture, ground shaking, and
<br />provide 2006 IBC/2007 CBC seismic design parameters.
<br />2. Open-Cut Trenching/Tunnel Shaft Excavation: Provide conclusions and recommendations for
<br />trenching/tunnel shaft excavation, anticipated ground behavior, safe temporary cut slopes,
<br />preliminary Cal-OSHA soil classification, clearance from existing utilities and protection of
<br />existing utilities, shoring guidelines including preliminary shoring pressure and surcharge
<br />pressure diagrams and vibration impacts, construction design groundwater level and
<br />construction dewatering criteria, pipe bedding and trench/tunnel pit excavation backfill
<br />materials and compaction specifications, suitability of native soil as trench/tunnel pit exca.vation
<br />backfill, backfill at existing utility crossings and the use of CLSM as pipe embedment and
<br />trench/tunnel pit excavation backfill, flexible and rigid pipeline external loading, Efc for flexible
<br />pipe design, soil corrosivity to uncoated steel and reinforced concrete, anticipated differential
<br />pipeline settlement and trench/tunnel pit excavation backfill settlement, ground improvement,
<br />if needed, and street repaving.
<br />3. Tunneling: Describe anticipated tunnel zone materials including grain size distribution, shear
<br />strength, tunnel design groundwater level" Tunnelrnan's Ground Classification and anticipated
<br />ground behavior, mixed-face and change-in-face conditions, soli strength and ability to support
<br />the tunneling equipment weight and vertical steering corrections, ground improvement along
<br />and below the tunnel zone, tunnel face stability, tunnel overcut limitations, systemic ground
<br />surface settlement estimate as a function of overcut, soli strength and cover depth" surface and
<br />subsurface settlement monitoring, contact grouting, minimum depth of cover and
<br />slurry/lubricant hydrofracture risks} minimum separations from existing utilities and critical
<br />utility monitoring, shaft construction as a function of soil and groundwater conditions, break-In
<br />and break-out portal stability and ground treatment/dewatering at launching and receiving
<br />shafts} preliminary estimate of jacking forces} limitations on pipe selection, annular space
<br />grouting for two-pass pipe jacking, jacking thrust block and/or reaction wall design parameters"
<br />ground treatment behind reaction walls, placement of intermediate jacking stations, shaft
<br />recompression settlement upon backfilling, and definition of obstructions for contract
<br />documents.
<br />4. Permanent Structures: Pertinent recommendations described above for open-cut
<br />trenching/tunnel pit excavation (e.g., those applicable to shoring, dewatering, excavation and
<br />backfilling, etc.). Provide conclusions and recommendations for allowable soli bearing c~paclty,
<br />total and differential foundation settlement estimates, anticipated differential pipeline
<br />settlement at tunnel to manhole connectIons and required range of deflection in flexible
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