2. Each block has a weight of 400 lb. Determine how far the force P can compress the spring until block B slips on block A. What is P for this to occur? The inclination between the block is 5-12 Equd Mct. Calcoloter k = 800 lb/ft μ's = 0.5 30° 5 B A 12 s=0.2

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

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 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.

For the data given in this problem, determine the magnitude of the active thrust on the wall retaining a c soil, using the procedure discussed in Section 16.10. Given H = 15.0 ft, c = 100 lb/ft2, = 26, = 115 lb/ft3, kv = 0, and kh = 0.3.

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?