Effect of inclined water table level on bearing capacity of cohesive soil

  • Upendra M
  • Venkateswarlu P
  • Shiva Prasad K.
  • J.B. Patel
Keywords: Bearing capacity; Settlement ratio; circular footing

Abstract

The bearing capacity of footing is considerably governed by soil settlement. Water table depth, footing dimensions, loading type etc., are various factors which affect the bearing capacity of soil. Depth of water table was considered in the study to find out the effect on bearing capacity. From the Terzaghi’s bearing capacity theory, water table depth corrections were applied to the ultimate bearing capacity of soil. These levels of water table are parallel to the base of the footing at a distance b from the ground surface. In this paper an attempt was made to find out the bearing capacity of cohesive soil with the presence of level of water table inclined 45 degrees to the base of the footing. The idea of the study is generally soil exists in stratified alternative layers of soil. If the aquifer layer of soil exist below the foundation is inclined and the level of water table is inclined below the foundation. A shallow depth, surface loading, smooth base mild steel circular footing (diameter(B)-50mm, height-50mm) was used in the study. The WTD maintained at different elevations, where the ratio of depth of water table below the base (b) to the base width of the footing (B) are 0, 1, and 2. The samples were kept 96 hours for soaking. Tri-axial test loading frame was used to apply compressive force at a strain rate of 1.25 mm/min. The 10% of settlement ratio ((settlement/width of footing)×100) was considered for the computation of ultimate bearing capacity. This paper emphasizes on the particular topic of the inclined water table depth effect on the bearing capacity of soil.

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Published
2018-10-05