Simplified strut-based model for cracking of infill walls due to excavation-induced distortions

Conventionally, damage in adjacent structures to excavations is evaluated considering the adjacent facilities as deep beams in which the stiffness is varied to represent the different building types. For frame buildings, this approach may not be appropriate given the interaction of the frame and the infill walls. This study presents a simplified model to determine the critical distortion and damage in infill panels of frame buildings due to excavations. The interaction between the infill panel and its bounding frame elements is evaluated by representing the wall as an equivalent strut; thus, the likelihood of cracking on each floor of the building can be evaluated independently. The presented approach neglects the effects of transverse beams and RC slabs on the cracking of the infill walls. The presented approach is compared with a data set of published experimental results to assess its validity and limitations. Although the original development of the strut model was based on horizontally loaded frames, using a factor of 1/3 for the cracking strain of the masonry was deemed satisfactory in light of the experimental results.