Problem Sheet 3 Questions

Question 1

A square concrete section of dimensions a by b of length 12m is driven through a dry sand. You are given the critical friction factor and the unit weight of the soil.

What is the 4 step process to finding the design resistance of the pile?

Answer 1

1 - Find the design material parameters
2 - Find the end bearing resistance
3 - Find the shaft resistance
4 - Find the total resistance by applying safety factors

Question 2

A signle, weightless pile of diameter 0.4m is driven 8 m into ground

W.T 1.5m below ground surface.
0-5m sand A
5-8m sand B

How would you find the design resistance?

Answer 2

1 - Find design parameters, being the critical andgle and K

2 - Find end bearing resistance, using the critical angle at the lowest sand,

3 - Find skin resistance of the 3 zones ( using effective stress )

4 - Find total resistance.