Differential Settlement Effect on RC Framed Structures

Differential settlement could be triggered by many factors within the soil strata, including frost heave, seismic activities, collapse of sinkholes, poorly compacted soil, or adjacent excavation activities. Such activities result in an uneven relaxation within the soil, forming undesirable settlements and imposing stress conditions, which are unaccounted for in the design process. Ground settlements can inflict serious, and in some cases, irreparable damage to pre-existing structures. Understanding the impact such settlements could have on structural systems is vital in developing effective preventative measures that would help mitigate such effects. Hence, this study investigates the effects of the differential settlement on a reinforced concrete framed structure by examining the structural behaviour considering different spans and heights. The nonlinear behaviour of the structure is simulated through two-dimensional (2D) frame finite element simulations. The propagation of mechanical damage within the structural members and the plastic hinge formation with respect to the induced settlements are then analyzed. The affect of ductility on the frame’s behaviour is demonstrated, and comparisons with settlement tolerances proposed in literature are drawn to assess the effectiveness of these limits.