Question

A long strip footing foundation will be used to support a concrete masonry- bearing wall for a business building. The footing will be 2m wide and 45 m long. The wall loading imposed onto the foundation will be 200 kN per meter of wall length.

i) Using both the 2:1 approximate and Boussinesq methods, determine the vertical stress increase (∆σ) at 3m below the footing center.

ii) Compare and discuss the ∆σ values calculated from the two methods.

Answer 1

1. 2.1 metod: (122) soo L>>>s. (Betanz) (L+2nz) (L+202)~L 200 kn 45m (2+2 (2) (3)) Δσ 200kn (us) (14) 0.317 kN/m².. Do = Bousinesques method: so = 30 (1+2) 273² 15/2 do 3(200) Jacasz (He 16 Bor 600 22 (9) Doa 10.61 kN/m². (:). (or) > (80): 1 method Bousi . In this care Bousiness ay is giry mae value than 21 /melas