Question

7. Pile cap foundation design A pile cap foundation systems is a thick concrete mat that rests on concrete or timber piles that have been driven into soft or unstable ground to provide a stable foundation for bridge piers as shown in the figure below In this example, each bridge pier is built on piles with length of 15 m and diameter of 0.5 m. The modulus of elasticity of the pile is 6890 MPa. The soil provides a frictional resistance along the piles length that varies linearly fro w 0 at y 0, to w 60 kN/m at y-15 m. The displacement at the end of the pile (y15 m) can be assumed 0 similar to problem 4 The total load acting on the pile cap is 3000 KN for each bridge pier. What's the minimum number of piles required to limit the total deflection of the bridge to 5 nm? It can be assumed that other components of the bridge remain rigid compared to the piles. The effect of the pile cap to reduce the deflection can also be ignored IIm1 Pier Cap → Pier Pile Cap

Answer 1

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