Enhancing the Resilience of Urban Buildings Against Extreme Wind Events: Evaluation, Mitigation, and Diagnostic Approaches

Abstract

Urban buildings could be significantly affected by exceptionally severe environmental actions, particularly those related to extreme wind. Therefore, it is convenient the urban buildings adaptation to face the incoming environmental risks due to wind actions with mitigation of their adverse effects and improvement of corresponding resilience. In reinforced concrete buildings (RC buildings) with infilled masonry walls, the capacity of the building`s envelope to face intense wind actions could be critically dependent on the mechanical resistance of their unreinforced masonry (URM) infill walls. The facade of reinforced concrete buildings (RCS buildings) could be subjected, due to wind, to intense out-of-plane (OOP) and in-plane (INP) loads, which could cause cracking in URM infill walls and consequently adversely affect, in certain severe situations, the safety of those buildings. Wind is usually related to normal climatic actions, but could also be linked to the effects of climate change, which have continuously increased lately. Moreover, the out-of-plane (OOP) capacity of URM infill walls related to wind action can be affected by vertical deformations. Therefore, specific knowledge of the type of damage due to wind loads is required to ground adequately the measures to minimize, particularly, the cracking of walls. Initially, basic elements about wind loads on facades are presented. Experimental investigations into the mechanical behavior of block masonry infill walls (compression tests) are analyzed, and related discussions of the results are made. Subsequently, discussions and analyses concerning the behavior of the walls under in-plane and out-of-plane wind loads are made. The influence of previous vertical deformations of the supporting elements on the out-of-plane (OOP) capacity of the URM infill walls to face the OOP wind loads is also analyzed. Relevant aspects of the mitigation of cracking due to wind loads and strategies for strengthening and repair are discussed. Finally, in the context of monitoring cracking of the URM infill walls.