A concrete beam symmetrical I-section spanning 8m has flange width and thickness of 300mm and 60mm respectively. The overall depth is 400mm. The thickness of the  of the web is 80mm. The beam is prestressed by a parabolic cable with eccentricity of 150mm at the center and zero at the supports with an effective force of 100kN. The live load on the beam is 2kN/m. Draw the stress distance diagram at central section for a) prestress + self weight (Unit weight of concrete =24kN/m^3) b) prestress + self weight + Live load) .

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.

A planned flexible load area (see Figure P7.2) is to be 3 m × 4.6 m and carries a uniformly distributed load of 180 kN/m2. Estimate the elastic settlement below the center of the loaded area. Assume that Df = 2 m and H = . Use Eq. (7.4).

A beam is part of the framing system for the floor of an office building. The floor is subjected to both dead loads and live loads. The maximum moment caused by the service dead load is 45 ft-kips, and the maximum moment for the service live load is 63 ft-kips (these moments occur at the same location on the beam and can therefore be combined). a. If load and resistance factor design is used, determine the maximum factored bending moment (required moment strength). What is the controlling AISC load combination? b. What is the required nominal moment strength for a resistance factor of 0.90? c. If allowable strength design is used, determine the required moment strength. What is the controlling AISC lead combination? d. What is the required nominal moment strength for a safety factor of 1.67?

The cross section of a braced cut supporting a sheet pile installation in a clay soil is shown in Figure 14.22. Given: H = 12 m, clay = 17.9 kN/m3, = 0, c = 75 kN/m2, and the center-to-center spacing of struts in plan view, s = 3 m. a. Using Pecks empirical pressure diagrams, draw the earth-pressure envelope. b. Determine the strut loads at levels A, B, and C.

Determine the maximum column load that can be applied on a 1.5 m 1.5 m square foundation, placed at a depth of 1.0 m within a soil, where = 19.0 kN/m3, c = 10 kN/m2 and =24. Allow a factor of safety of 3.0.

A flexible circular footing of radius R carries a uniform pressure q. Find the depth (in terms of R) at which the vertical stress below the center is 20% of q.

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