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The aim to retrofit and preserve the monumental stone masonry buildings due to their historical and cultural relevance is accompanied by the necessity of understanding the behaviour of the unstrengthen structure, as well as its behaviour after the strengthening systems are applied. There is scarce information related to the mechanical properties of stone masonry buildings and even less regarding the assessment of these characteristics in numerical models. Therefore, simulating the force displacement variation and the stress-strain distribution of stone masonry loaded in diagonal compression is a challenging issue. This work contributes to this topic by developing two detailed micro non-linear 3D models. The first model was designed for an unreinforced masonry (URM) wall and the second one was developed for a strengthened URM wall. For this purpose, a commonly used seismic strengthening system, referred to as reinforced plastering mortar (RPM) or textile reinforced mortar (TRM) was applied on the wall. All the components of the TRM strengthening system and the interfaces between the system and the stone masonry wall were considered in the numerical model. The structural responses of the models were analysed and compared and the TRM system effectiveness in increasing the in-plane load resistance and ductility of stone masonry walls was highlighted.

The investigation of the interlaminar damage evolution on multi-layered composites as well as the numerical modelling techniques available for the simulation of the interface delamination are still a current concern. The complexity of modelling the mechanical behaviour and fracture modes of composite laminates is increased because of the anisotropic behaviour of the material, the fibre arrangement or other important parameters, such as stacking sequence, fibre orientation angle and the configuration of the composite laminates. Different failure modes may occur on multi-layered composites, which can lead to significant stiffness and strength reduction or to the complete loss of the load carrying capacity. The interlaminar stresses are the main factors responsible for the initiation and growth of the interlaminar failures such as delamination. They may occur as a result of manufacturing defects, low-velocity impacts or as an effect of the presence of the free edges. The delamination onset can lead to serious problems such as the premature buckling of the laminates, moisture infiltration, and stiffness degradation or even to progressive delamination growth and the separation of the layers of the composite laminates. The paper presents the numerical modelling of a multi-layered composite subjected to the tensile opening fracture mode as well as the investigation of the delamination growth. The purpose of the analysis is to study the delamination evolution on a symmetric composite laminate, starting from a pre-existing initial crack, at the interface between the adjacent layers from the middle plane. Thenumerical modelling approach for the simulation of the delamination evolution is conducted based on the Cohesive Zone Method. The results are presented in terms of the total displacement jump and equivalent stress distributions on the layers of the composite laminates.

Due to the continuous development of the transportation sector and the industrial areas, the roads network has become complex nowadays. The administrators of these networks are thus responsible for maintaining it in proper conditions, using the limited budget available, insufficient for the many structures and problems identified across the network. Therefore, effective systems have been created and developed to prioritize the required works, and the benefits of their implementation have been ascertained from the early stages of the degradation development. One of these systems is the modern methodology for assessing the structural state of bridges, called Structural Health Monitoring (SHM), responsible for discovering and monitoring the degradation occurrence and development. In this paper, the authors present the numerical modelling and the dynamic analysis of a bridge with mixed steel-concrete structure. The bridge is located in Romania, ensuring the continuity of DN 28 road near Scheia. The bridge superstructure, 220.70 m in length, was fully modelled using the SAP2000 program, highlighting the specific behaviour of a continuous girder. The frequencies and deformations for the first four vibration modes were determined. The data will be used in a forthcoming experimental study and compared to those recorded in-situ, in order to determine the structural degradation.

Unreinforced masonry (URM) structures represent a large share of the dwelling stock, traditional industrial buildings and historical heritage of mankind. Most of the URM structures have been built with little or, in some cases, no seismic provisions. In order to overcome this drawback, the application of external reinforcement layers, especially those made of composites, to improve the structural behavior of masonry structures has been a research focus area during the past decades. The aim of this paper is to propose and assess a simplified and accepted Finite Element (FE) modelling strategy to simulate the diagonal compression test of the URM walls strengthened with glass fibre meshes embedded in a cement-based mortar. In the case of masonry walls strengthened with composites reinforced with glass fibre meshes, both the masonry material model and the modelling and the meshing of the composite strengthening system need to be addressed by taking into account the complex phenomena that characterise the bond interaction between the glass fibre mesh, mortar and the masonry support. The FE analyses were developed with reference to the experimental tests available in the current literature and, according to the preliminary outcomes of an experimental program which is currently under development at the Faculty of Civil Engineering and Building Services, Iasi.