Reference no: EM131227010

Round off your results appropriately in each case. Work without appropriate UNITS will be returned without grading.

Note: Total allowable settlement = 25 mm.

Q1. Fig.1 shows the soil profile and Table below shows the SPT N data. Bore hole size = 100 mm. Standard split spoon sampler and standard energy were applied for SPT tests.

Apply rod-length corrections, and overburden stress correction. Determine (N₁)₆₀, estimate relative density Dr, friction angle Φ', and modulus E and plot all of them in a figure. Depth must be plotted increasing downward in the figure. Appropriate scale must be used for axes.

Q2. Determine the allowable bearing stress q_all based on both, tolerable settlement and ultimate bearing capacity qult with at least FS=3, for the following cases (a) to (c).

Use (a) Terzaghi & Peck method, as well as (b) Schmertmann's method (use simplified Iz diagram) for settlement calculations. Ignore creep settlement.

a) Strip Footing, B= 1.75m, Depth of embedment = 1m.

b) Rectangular Footing: B=1.75m, L=2B, Depth of embedment = 1m.

c) Circular Footing (same cross sectional area as (b)). Depth of embedment = 1m.

d) Determine the allowable Load Q for a, b, and c. Depth of embedment = 1m. Neatly tabulate your results.

Fig.1: Soil Profile at a Site

Sand

Assume moist unit weight = 16.4 kN/m³

Ground water (1m below ground level), Assume saturated unit weight = 18.5 kN/m³;

Unit weight of water = 9.81 kN/m³

Bedrock at 15m depth

Depth	SPT
m	Nm
0
1	10
2	12
3	16
4	8
5	10
6	12
7	15
8	13
9	16
10	20