Spatially random modulus and tensile strength: Contribution to variability of strain, damage, and fracture in concrete

Abstract

This paper explores the computational modeling of nonlocal strain, damage, and fracture in concrete, considering the isolated contribution of two random, spatially variable properties related to the fracture process: Young’s modulus (E) and tensile strength (ft). Applying a continuum damage model, heterogeneous specimens of concrete with random and spatially varying E or ft were found to produce substantial differences when contrasted with traditional homogeneous (non-random) specimens. These differences include variable and uncertain strain and damage, wandering of the failure paths, and differing (sometimes lower) peak forces, i.e. increased probabilities of failure in the heterogeneous specimens. It is found that ft variability contributes more (from 1.7 to up to 4 times more, depending on the parameter) to the overall performance variability of the concrete than E variability, which has a comparatively lower contribution. Performance is evaluated using (1) force-displacement response, (2) individual, average, and standard deviation maps of non-local strain and damage, (3) fracture paths and strain and damage values along the fractures. The modeling methodology is illustrated for two specimen geometries: a square plate with a circular hole, and an L-shaped plate. The computational results correlate well with reported experimental data of fracture in concrete specimens.

Durability Test and Mechanical Properties of CFRP Bolt under Accelerated Corrosion Conditions

“…e strength and ductility of both are reduced and the stiffness is basically unchanged under freeze-thaw cycles. However, in general, CFRP-and GFRP-reinforced structures still show good performance in harsh environment, and the effect of freezethaw cycle is greater on CFRP and GFRP than that of the dry-wet cycle [6]. Elgohary et al simulated the long-term working environment around concrete beams repaired by FRP through the short-term acceleration test.…”

A simple implementation of localizing gradient damage model in Abaqus

“…The localizing gradient enhancement was shown to work well for different problems, e.g. quasi-static fracture of quasi-brittle materials (Castillo et al., 2021; Sarkar et al., 2019; Shedbale et al., 2021; Tong et al., 2021b), size effects in quasi-brittle fracture (Negi et al., 2021; Zhang et al., 2021), thermo-mechanical fracture (Sarkar et al., 2020), continuous-discontinuous modelling (Sarkar et al., 2021), dynamic fracture (Wang et al., 2019) and ductile fracture (Xu et al., 2020; Xu and Poh, 2019).…”

A multi-scale model from microscopic cracks to macroscopic damage of concrete at elevated temperatures

“…Nowadays, concrete has long been used in various engineering structures such as buildings, utility tunnels, nuclear power plants, and so on (Ahmed et al., 2021; Bai et al., 2022a; Bao et al., 2023; Castillo et al., 2021; Park et al., 2022; Shen et al.,2021; Sun, 2022; Sun et al., 2020; Sun and Xu, 2022; Voyiadjis et al., 2022; Wu et al., 2022; Xu et al., 2018). During the service periods of the engineering structures, fire risk is unavoidable (Aslani and Samali, 2015; Nuruzzaman et al., 2023; Sun et al., 2022a; 2023).…”