Miscellaneous engineering services

Tender description

This Contract involves the Geotechnical Investigation into the A361 / A39 North Devon Link Road from the Borner's Bridge Junction at South Molton to the Buckleigh Road Junction near Bideford. This Contract involves the Geotechnical Investigation into the A361 / A39 North Devon Link Road from the Borner's Bridge Junction at South Molton to the Buckleigh Road Junction near Bideford. The ground investigation will comprise the following works: — The excavation of mechanically dug trial pits to a maximum depth of 4 m or refusal. — Windowless sample borehole drilled by a dynamic sampling rig to depths as given in the Procurement Documents or refusal on rockhead. This is to include in-situ Standard Penetration Testing (SPT) and undisturbed sampling. Hand-dug starter pits shall be excavated at all exploratory borehole locations. — Combine dynamic sample / rotary open hole / rotary cored boreholes to depths as given in the Procurement Documents. This is to include in-situ Standard Penetration Testing (SPT) and undisturbed sampling. Hand-dug starter pits shall be excavated at all exploratory borehole locations. — Excavation of hand-dug trial pits in sides of existing cuttings and removal of vegetation to expose underlying rock mass to facilitate kinematic analysis. — Excavation of hand dug pits at base of cutting where inaccessible to mechanical excavation/boring methods. — Installation of groundwater monitoring standpipes in boreholes to a depth specified by the supervising engineer. Monitoring standpipes shall be 19 mm diameter or greater. — In-situ determination of California bearing Ratio (CBR) — to be undertaken using Dynamic Cone Penetration (DCP) equipment. The number and location of DCP tests required to provide sufficient coverage will be determined on site by the Investigation Supervisor. — Groundwater monitoring is to be conducted following the completion of site works at intervals determined by the Investigation Supervisor. All installations shall be monitored to establish the elevation of groundwater. — Geotechnical Laboratory testing on selected samples. — Environmental/Chemical Laboratory testing on selected samples. — Specific borehole requirements and Borehole location plans are detailed within the Procurement Documents. — Provide Devon County Council with a Ground Investigation Report and Interpretation Report, plus design support.