(c) Calculate the load and the stress on each pillar before and after the 800m underground excavation, in the plan view shown below. Two types of pillars are present: Pillar type A is 2m by 2m in cross section and Pillar type B is 6m by 2m, as shown below. Assume a rock mass density of 24 kN/m³. (15 marks) 2+2+6+6+2+2+3=23m A₁:2x2m B₁ 6x2m 6@2m 6@2 m =12m B₂ =12 m k 2+6+4+2+4+2+3=23m

(c) Calculate the load and the stress on each pillar before and after the 800m underground excavation, in the plan view shown below. Two types of pillars are present: Pillar type A is 2m by 2m in cross section and Pillar type B is 6m by 2m, as shown below. Assume a rock mass density of 24 kN/m³. (15 marks) 2+2+6+6+2+2+3=23m A₁:2x2m B₁ 6x2m 6@2m 6@2 m =12m B₂ =12 m k 2+6+4+2+4+2+3=23m

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter8: Applications Of Plane Stress (pressure Vessels, Beams, And Combined Loadings)

Section: Chapter Questions

Problem 8.5.16P: A sign is supported by a pipe (see figure) having an outer diameter 110 mm and inner diameter 90 mm....

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