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The failure of a laminated glass beam is investigated by two full discrete numerical approaches: a Rigid Body-Spring Model (RBSM) and a mesh-free numerical method arising from bond-based Peridynamics (PD). The brittle nature of the failure has been modelled and investigated by exploiting the discrete nature of these models, and specifically the PD which allows the bond/spring strengths to be explicitly related with the size and orientation of the defects in the structure. Strength values have been assigned randomly, within the beam, by a Monte Carlo simulation, according to Weibull statistical distributions calibrated on experimental results obtained from literature. For the first time, the differences and analogies of the two discrete approaches are shown and discussed together with the analysis of variability of the load capacity of the beam related to the statistical presence of flaws in the structure. Results show that, due to the heterogeneous strength properties of the numerical models and mechanical features of the inter-layer, multiple cracking stages can be distinguished for the structural element, thus different cumulative distribution function of limit load can be obtained. [ABSTRACT FROM AUTHOR]

• Thermal cracking on massive reinforced concrete (RC) member was quantitatively evaluated. • Newly proposed constitutive laws on the 3D-RBSM were proposed for this objective. • Crack width and crack spacing of massive RC walls subjected to external restraint were evaluated. • Time-dependent cracking behavior of a massive RC wall structure was clarified. • Impacts of factors affecting thermal cracking were studied using the proposed method. This study aimed to develop a numerical method to evaluate thermal cracking, in terms of parameters such as thermal crack width and crack spacing, on massive reinforced concrete (RC) wall structures externally restrained by a base structure. The existing experimental study was investigated using the rigid body–spring model (RBSM) with new constitutive laws developed for this objective. Thermal cracks, which localized and propagated throughout the wall thickness, were successfully reproduced, and the good agreement with the experiment indicated the capability of the proposed numerical method. The time-dependent cracking behavior and the impacts of factors affecting thermal cracking, which are difficult to investigate experimentally, are discussed. [ABSTRACT FROM AUTHOR]

• Even surface cracking conditions are similar, internal stress and cracking vary greatly. • Strength and stiffness can increase with expansion in case of coupled damage. • Internal cracking and stiffness are important to estimate structural performance. Real concrete structures can suffer simultaneously from the alkali-silica reaction (ASR) and delayed ettringite formation (DEF), resulting in expansion of the concrete and surface map cracking. This damage can lead to serious durability problems. The respective effects of ASR and DEF have been studied, but the cracking behavior of concrete when they act together remains unclear. In this study, a three-dimensional rigid body spring model (3D RBSM) is used to simulate the cracking and mechanical property degradation of concrete under coupled ASR and DEF. A parametric study is conducted to understand various combinations of ASR and DEF. In line with previous studies by the authors on independent ASR/DEF damage, expansions caused by ASR and DEF are, respectively, introduced as strains at the mortar-aggregate interface and in mortar elements. Due to a confinement effect, specimens subjected to coupled expansion may suffer less expansion or cracking than when only one of the degradations is acting. The model clearly visualizes the cracking process and stress development as the degree of coupled expansion increases. More importantly, based on the simulated results, the interactions of the two types of expansion are revealed by correlating the degradation in mechanical properties with internal cracking behavior. Further, the confinement effect arising on application of the second type of expansion is quantitatively examined. While there is no significant change in stiffness, compressive strength in some cases increases with expansion as larger cracks close up under the confinement effect. This kind of investigation of coupled effects is difficult to quantitatively analyze through experimentation, but this work demonstrates that it is possible using RBSM simulations. [ABSTRACT FROM AUTHOR]

• Different damage configurations of 3 layers tempered glass plate were investigated. • The contribute of compressed layer after reloading is evaluated by meso-scale RBSM. • A macro-scale RBSM has been implemented to predict the out-of plate response. The mechanical response of a plate made of a three layers laminated tempered glass (LG) with different damage configurations has been investigated and modelled by a rigid body-spring numerical approach. Experiments showed that the mechanical contribution of one or more fractured glass plies cannot be disregarded when evaluating the global stiffness of a damaged LG plate, as well as with regard to the effective stress distribution in the undamaged plies. A micro-scale analysis was performed by means of an in-plane Rigid Body-Spring Model (RBSM) to study the membrane response of a single fractured layer when subjected to a simple compression loading. Then, a macro-scale approach was adopted for modelling the out-of plane response, in which the actual distribution of the broken fragments was neglected, through a phenomenological constitutive law that assumes the response at the sectional level. The two step procedure, with the proposed phenomenological laws adopted for the damaged layers, proved to be effective in predicting the different experimental results of the three point bending tests on partially damaged laminated plates. [ABSTRACT FROM AUTHOR]