A grade beam AB supports three concentrated loads and rests on soil and the top of a large rock. The soil exerts an upward distributed load, and the rock exerts a concentrated load RR as shown. Knowing that w_B = 0.4wA, determine 

(a) The largest value of P for which the beam is in equilibrium, 

(b) The corresponding value of w_A. In the following problems, use γ = 62.4 lb/ft³ for the specific weight of fresh water and γ_c = 150 lb/ft³ for the specific weight of concrete if U.S. customary units are used. With SI units, use ρ = 10³ kg/m³ for the density of fresh water and ρc = 2.40 × 10³ kg/m³ for the density of concrete. (See the footnote on page 222 for how to determine the specific weight of a material given its density.)

Transcribed Image Text:

0.4 m 15 m 0.5 m IS EN 24 KN -LS m -1.2 m