Tensile Fracture Mechanism of Masonry Wallettes Parallel to Bed Joints: A Stochastic Discontinuum Analysis

Abstract

Nonhomogeneous material characteristics of masonry lead to complex fracture mechanisms, which require substantial analysis regarding the influence of masonry constituents. In this context, this study presents a discontinuum modeling strategy, based on the discrete element method, developed to investigate the tensile fracture mechanism of masonry wallettes parallel to the bed joints considering the inherent variation in the material properties. The applied numerical approach utilizes polyhedral blocks to represent masonry and integrate the equations of motion explicitly to compute nodal velocities for each block in the system. The mechanical interaction between the adjacent blocks is computed at the active contact points, where the contact stresses are calculated and updated based on the implemented contact constitutive models. In this research, different fracture mechanisms of masonry wallettes under tension are explored developing at the unit–mortar interface and/or within the units. The contact properties are determined based on certain statistical variations. Emphasis is given to the influence of the material properties on the fracture mechanism and capacity of the masonry assemblages. The results of the analysis reveal and quantify the importance of the contact properties for unit and unit–mortar interfaces (e.g., tensile strength, cohesion, and friction coefficient) in terms of capacity and corresponding fracture mechanism for masonry wallettes.

In-plane structural performance of dry-joint stone masonry Walls: A spatial and non-spatial stochastic discontinuum analysis

“…Note that the stiffness values presented in this table are the multipliers for stiffness, whereas the mean values of other parameters are taken from Table 4. Normal distribution was assumed for the elastic stiffness and friction angle parameters, following the pertinent literature [22,57,59,60]. The tensile strength of the masonry units is assigned with a lognormal distribution to prevent negative values during sampling, with a slightly higher coefficient of variation given the larger scatter found in tests.…”

On the Use of the Digital Twin Concept for the Structural Integrity Protection of Architectural Heritage

“…Given the stochastic nature of masonry properties, probabilistic structural models that consider uncertainties and analyse their effects on the response can be reliable for addressing problems associated with random variables. Recently, some researchers have explored these models [55][56][57]. Furthermore, hybrid models that combine numerical and probabilistic analysis can be generated to assess the structural response of masonry structures, including the effect of uncertainties.…”

Effect of Precompression and Material Uncertainty on the In-Plane Behavior of URM Pier–Spandrel Systems

“…Additionally, it is noted that the elastic stiffness of the lintel was considered constant during the analyses (adopted as E lintel = 0.3 GPa). A normal distribution was used for compressive strength and friction angle parameters, whereas a lognormal distribution was assigned to the tensile strength of units and joints, complying with the earlier work of the authors and the pertinent literature [5,7,16,77,78]. The variables and their statistical distributions are presented in Table 1.…”

“…This phenomenon yields localized cracks in the form of joint openings and sliding along the head and bed joints in URM walls. Conversely, weak unit-strong joint action causes opposite behavior, in which the cracks predominantly pass through the masonry units [15][16][17]. In each combination of masonry constituents, progressive damage can be noticed in URM walls subjected to lateral loading due to successive failures at the masonry units and mortar joints.…”