3. Building Technology

Foundations — Quiz

Test your understanding of foundations with 5 practice questions.

Practice Questions

Question 1

How does a water table located at a shallow depth relative to the base of a shallow footing influence its bearing capacity and settlement behavior?

Question 2

Using Terzaghi’s bearing capacity equation for strip footings, calculate the ultimate bearing capacity $q_u$ for a cohesive‐frictional soil with cohesion $c=25\,\mathrm{kPa}$, internal friction angle $\phi=30^\circ$, unit weight $\gamma=18\,\mathrm{kN/m^3}$, footing width $B=1.5\,\mathrm{m}$, and depth $D_f=1\,\mathrm{m}$. Use $N_c=30$, $N_q=18$, and $N_\gamma=20$. Show your calculation.

Question 3

Why might a designer choose a strap (cantilever) footing for two columns with unequal loads instead of two isolated footings?

Question 4

For a required pile skin friction capacity of $400\,\mathrm{kN}$, pile diameter $D=0.30\,\mathrm{m}$, and unit skin friction $f_s=50\,\mathrm{kPa}$, what embedment length $L$ is needed? Show your calculation.

Question 5

In seismic zones, which foundation design modification is commonly used to reduce earthquake forces transmitted to the structure?