Structural Response of Unreinforced Masonry Walls

Abstract

Historical buildings located in seismic regions have URM (unreinforced masonry) walls of considerable width as their main structure. In order to study the structural response of such type of masonry, it is necessary to know its mechanical and elastic characteristics. For such purpose, it is generally necessary to perform destructive and non-destructive tests. Other procedures, such as the study of masonry through numerical models, would make it possible to predict, with close approximation, the response of masonry to different actions. The purpose of this paper is to evaluate the behavior of URM walls subjected to axial and horizontal load by using a finite element model with the Abaqus code. Constitutive laws of materials, bricks and mortar are defined, using two constitutive models of plasticity and damage included in the materials library. The constitutive models used employ information of experimental tests performed on bricks and mortar. The results of an analysis for an URM wall subjected to axial and horizontal load are presented. Responses of walls were obtained in terms of load versus displacement for different constitutive models and for different qualities of bricks and mortar. The two constitutive models used show similar results, particularly in the response waveforms. However, the ultimate capacity values show mean variations of around 30%. The two constitutive models display high dependence upon the mechanical characteristics of bricks and mortar.

Deformable nose design for the non-penetrating projectile

“…Table 2: Properties of plastic and failure for CK45 steel [31 and 32] and aluminum AL2024-T3 [33] Table 3: Characteristics of the plastic behavior of brick wall and cargo [34] In Table 3, y  is yield stress, Fb 0 /fc 0 is maximum two-axis to single-axis compressive stress ratio, and K is the second constant ratio of the stress tensor on the tensile meridian to the same parameter on the pressure meridian. The dilation angle determines the amount of lift due to shear displacement.…”

“…The eccentricity cuts off the flow potential function at the beginning of the horizontal axis of the hydrostatic stress at an angle of 90 degrees. In fact, the function will be a curve under that condition [34].…”