Geotechnical Course Project
Task: Design of temporary support for an excavation for a cut-and-cover tunnel for a major highway project.
Dimension of excavation: Depth 1.5m, Width 30m
Geotechnical information: BH114 & BH115, Groundwater table at 1.5m depth
Design criteria:
1) Maximum wall deflection 50mm,
2) Maximum ground settlement 30mm,
3) Minimum FoS against piping 1.5,
4) Minimum FoS against basal heave 1.5,
5) Minimum FoS against blow-in 1.5, and
6) Minimum FoS for wall stability 2.0.
Design assumptions:
1) No drawdown of groundwater table outside excavation,
2) Groundwater table lowered to 1m below base of excavation, and
3) Surcharge load adjacent to excavation 20kPa.
Walling system:
1) Diaphragm wall,
2) Sheetpile wall, or
3) Contiguous bored pile wall.
Bracing system:
1) Internal struts,
2) Ground anchors, or
3) Any suitable systems.
Required design output: 1) Walling system (type, size & depth),
2) Bracing system (type, size and arrangement),
3) Construction sequence, and
4) Demonstration of design meeting design criteria.
Attachment:- Geotechnical engineering.zip