The effect of masonry infills on the seismic response of a four-storey reinforced concrete frame — a deterministic assessment

The fundamental period is one of the most critical parameters for the seismic design of structures. There are several literature approaches for its estimation which often conflict with each other, making their use questionable. Furthermore, the majority of these approaches do not take into account the presence of infill walls into the structure despite the fact that infill walls increase the stiffness and mass of structure leading to significant changes in the fundamental period. In the present paper, artificial neural networks (ANNs) are used to predict the fundamental period of infilled reinforced concrete (RC) structures. For the training and the validation of the ANN, a large data set is used based on a detailed investigation of the parameters that affect the fundamental period of RC structures. The comparison of the predicted values with analytical ones indicates the potential of using ANNs for the prediction of the fundamental period of infilled RC frame structures taking into account the crucial parameters that influence its value.

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Prediction of the fundamental period of infilled RC frame structures using artificial neural networks

Mechanical properties of kenaf fiber reinforced concrete

https://www.research.manchester.ac.uk/portal/files/59202227/Abdulla_et_al_ENGSTRUCT_2017.pdf

Simulating masonry wall behaviour using a simplified micro-model approach

An innovative numerical modeling strategy for the structural analysis of historical monumental buildings

The uniaxial monotonic compressive stress-strain behavior and other characteristics of unreinforced masonry and its constituents, i.e., solid clay bricks and mortar, have been studied by several laboratory tests. Based on the results and observations of the comprehensive experimental study, nonlinear stress-strain curves have been obtained for bricks, mortar, and masonry and six “control points” have been identified on the stress-strain curves of masonry, which can also be used to define the performance limit states of the masonry material or member. Using linear regression analysis, a simple analytical model has been proposed for obtaining the stress-strain curves for masonry that can be used in the analysis and design procedures. The model requires only the compressive strengths of bricks and mortar as input data, which can be easily obtained experimentally and also are generally available in codes. Simple relationships have been identified for obtaining the modulus of elasticity of bricks, mortar, and ...

/pdf/stress-strain-characteristics-of-clay-brick-masonry-under-27idyydbh4.pdf

Stress-Strain Characteristics of Clay Brick Masonry under Uniaxial Compression

Masonry infill MI walls are remarkable in increasing the initial stiffness of reinforced concrete RC frames, and being the stiffer component, attract most of the lateral seismic shear forces on buildings, thereby reducing the demand on the RC frame members. However, behavior of MI is difficult to predict because of significant variations in material properties and because of failure modes that are brittle in nature. As a result, MI walls have often been treated as nonstructural elements in buildings, and their effects are not included in the analysis and design procedure. However, experience shows that MI may have significant positive or negative effects on the global behavior of buildings and, therefore, should be addressed appropriately. Various national codes differ greatly in the manner effects of MI are to be considered in the design process from aseismic performance point of view. This paper reviews and compares analysis and design provisions related to MI-RC frames in seismic design codes of 16 countries and identifies important issues that

/pdf/code-approaches-to-seismic-design-of-masonry-infilled-2jw1f3oofw.pdf

Code Approaches to Seismic Design of Masonry-Infilled Reinforced ConcreteFrames: A State-of-the-Art Review

Behavior and failure mechanisms of masonry-infilled RC frames (in low-rise buildings) subject to lateral loading

Material stress-strain properties are required in the nonlinear analyses of structures. Stress-strain relationships for some construction materials such as concrete and steel are available in the literature and design codes. However, such relationships are not easily available for one of the most widely used construction material, i.e. masonry. In the present comprehensive experimental study, compressive stress-strain relationships for masonry are determined by testing 84 masonry prism specimens constructed using bricks from four different manufacturers and three mortar grades. By regression analysis of experimental data, analytical expressions are proposed to estimate the modulus of elasticity of masonry. An analytical model is proposed to adequately plot the stress-strain curves for masonry using six control points on the curves. A simplified analytical model is also proposed that can be conveniently used in finite element analysis programs.

Uniaxial compressive stress-strain model for clay brick masonry

Performance of structures in different areas of Sikkim, during the earthquake of 14 February 2006, is reviewed. The earthquake caused damage to heritage structures as well as modern buildings. Both masonry and reinforced concrete buildings showed poor performance. On the other hand, traditionally constructed wooden houses performed extremely well. The damage seen in and around Gangtok was clearly disproportionate to the size of the earthquake, which was a moderate 5.7 on the Richter scale. This very clearly establishes the high level of seismic vulnerability of the region. The damage is primarily attributed to poor design and construction practices, and lack of quality control. Urgent need for trained human resources and for creation of a system of checks and balances, to ensure safe constructions in Sikkim is highlighted.

/pdf/performance-of-structures-during-the-sikkim-earthquake-of-14-9in9i77x05.pdf

Hemant B. Kaushik

Papers

Stress-Strain Characteristics of Clay Brick Masonry under Uniaxial Compression

Code Approaches to Seismic Design of Masonry-Infilled Reinforced ConcreteFrames: A State-of-the-Art Review

Behavior and failure mechanisms of masonry-infilled RC frames (in low-rise buildings) subject to lateral loading

Uniaxial compressive stress-strain model for clay brick masonry

Performance of structures during the Sikkim earthquake of 14 February 2006