Analysis of combined strip footing undergoing alocal of support

Local subsidence beneath foundation may result from excavation for < temporary repairs, erosion by ground water, compaction, or by forming sinkholes. This subsidence eliminates the soil support beneath a portion of the foundation. The effect of this subsidence on the behavior of combined strip footing is investigated by using the method of finite element analysis. The soil support beneath the footing has been presented by springs at the nodes lying on the contact line of the soil-footing interface. The analysis has been made for different factors including footing height, coefficient of subgrade reaction. size of gap, and gap location. from these results, relationships between the dimensionless stresses. bending moments. contact stresses, and vertical displacements have been established for different values of the above mentioned factors. These relationships provide an insight into the effect of the gap presence, beneath the footing. on the footing behavior. Such relationships are vital in the development of a design procedure to assure the safety of combined strip footings undergoing loss of support.