The following subtended angles were read on a 2m long subtense bar using a theodolite:0°54' 13" , O°22'20 ", O°32'06", and 0°19' 46“. Compute the horizontal distance from the theodolite to each position of the bar. Show your solutions here.

A shallow square foundation for a column is to be constructed. It must carry a net vertical load of 1000 kN. The soil supporting the foundation is sand. The standard penetration numbers (N60) obtained from field exploration are as follows: FIG. 17.15 The groundwater table is located at a depth of 12 m. The unit weight of soil above the water table is 15.7 kN/m3, and the saturated unit weight of soil below the water table is 18.8 kN/m3. Assume that the depth of the foundation will be 1.5 m and the tolerable settlement is 25 mm. Determine the size of the foundation.

Determine the factor of safety against bottom heave for the braced cut described in Problem 15.18. Use Eqs. (15.66) and (15.70). For Eq. (15.70), assume the length of the cut, L = 18 m. 15.18 Refer to Figure 15.51 in which = 17.5 kN/m3, c = 60 kN/m2, and center-to-center spacing of struts is 5 m. Draw the earth pressure envelope and determine the strut loads at levels A, B, and C. FIG. 15.51

The water table at a site is at 5 m below the ground level, and it is required to excavate to this level. The soil profile consists of a thick bed of sand where the unit weight is m = 17.0 kN/m3 above the water table and sat = 20.0 kN/m3 below the water table. The friction angle of the sand is 37. The wall of the excavation will be supported by cantilever sheet piles. How deep would you drive the sheet piles? Use the simplified analysis (Figure 15.37) with a factor of safety of 1.5 on the passive resistance. Determine the maximum bending moment in the sheet pile and the required section modulus for the sheet pile section (given an allowable stress of 190 MN/m2).

EB and FG are two planes inside a soil element ABCD as shown in Figure 10.50. Stress conditions on the two planes are Plane EB: EB = 25 kN/m2; EB = +10 kN/m2 Plane FG: FG = 10 kN/m2; FG = 5 kN/m2 (Note: Mohrs circle sign conventions for stresses are used above) Given ; = 25, determine: a. The maximum and minimum principal stresses b. The angle between the planes EB and FG c. The external stresses on planes AB and BC that would cause the above internal stresses on planes EB and FG

A braced cut shown in Figure P19.3 is to be made to a depth of 9.0 m in a saturated clay deposit where the unit weight is 17.65 kN/m3 and the undrained shear strength is 30 kN/m2. The struts are spaced horizontally at 3.0 m center to center. Find the strut loads.