In-Plane Behavior of Confined Masonry Walls -With and Without Opening

Confined masonry buildings are used in rural and urban area sofiran. they performed almost satisfactoryduring past mod erate earthquakes oflran. there is not a methodology in iranian seismic code (standard 2800- 3rdedition) to est imate their capacities quantitatively: in line with remo ving this constraint, an attempt is made to studyin-plane behavior of two squared confined masonry walls with and without ope ning bv using a numeri calapp roach.these walls are considered based on iranian seismic code requirements. finit e element 2d models of the walls arede veloped and a pushover analysis is carried out . to model the non- linear behavior ofthe confined masonry walls , thefollowing criteria are used: (1) the rankine-hill yield criterion with low orthotropic factor to model the masonrypanel: (2) the rankine yield criterion to model reinforced concrete bond-beams and tie-columns: (3) the coulombfiction criterion with tension cutoff mode to model the interfa ce zone between the masonry panel and reinforc edconc rete members. for this purpose. the unknown parameters are de termined bv testing of masonry and concretesamples: and by finite element analysis. comparing the results show that the ini tial stiffness. the maximum lateralstrength and the ductilitvfactor of walls with and without opening are different . also, the severe compressed zones ofthe masonry panels within the confining elements are found different fro m what are reported for the masonry panelsof infilled fames by other researchers. this study shows that a further investigation is neededfor estimating capacityof confi ned masonry walls with and without open ing analytically and expe rimentally. also where openings, withmedium size are ex isted. the confi ning elements should be added around them. these issues can be considered in thenext revisions of iranian seismic code