Recommended Excavation Methods for an urban project
Recommended Excavation Methods for an urban project
(OP)
Hello every one,
I am dealing with an excavation of about 11' (~ 3.3 m) depth, and dimensions of 190' x 130', this will be an underground parking for a 4 story building. The soil is mostly sand with little silt and clay, not very cohesive. The project site is adjacent to two major streets from north and south, and the ground water level is almost 5' (1.5 m) below ground surface. The excavation will start in May and rain fall is expected.
Considering the above conditions, what method of excavation and equipment would you recommend specially for the two sides adjacent to the streets? What would you recommend to control the ground water in these sides? Sheet piles, slurry trenchs, point wells?
Thanks for your valuable suggestions.
I am dealing with an excavation of about 11' (~ 3.3 m) depth, and dimensions of 190' x 130', this will be an underground parking for a 4 story building. The soil is mostly sand with little silt and clay, not very cohesive. The project site is adjacent to two major streets from north and south, and the ground water level is almost 5' (1.5 m) below ground surface. The excavation will start in May and rain fall is expected.
Considering the above conditions, what method of excavation and equipment would you recommend specially for the two sides adjacent to the streets? What would you recommend to control the ground water in these sides? Sheet piles, slurry trenchs, point wells?
Thanks for your valuable suggestions.





RE: Recommended Excavation Methods for an urban project
RE: Recommended Excavation Methods for an urban project
RE: Recommended Excavation Methods for an urban project
RE: Recommended Excavation Methods for an urban project
RE: Recommended Excavation Methods for an urban project
If conventional then sheet piles would be my preferred option as mentioned in previous threads.
Should piles be undertaken, then a soldier pile system would be my option (perhaps could be incorporated into the design?). In terms of water control, I would be wary of well points that could draw the water table down and effect surrounding foundations (check what the other foundations comprise of). That could lead to unnecessary claims and problems. The use of a subsurface drainage system (we call it a geodrain in South Africa, essentially a french drain system) installed in the sand along the perimeter and centre of the excavation would collect/control the groundwater and surface runoff. The geodrain could then be connected to a sump collection point and discharged. A cheaper solution to other dewatering methods.
How thick is the sand beneath the founding level? and what does the underlying geology comprise of?
Hope this is of help.