Capacity evaluation of composites with new materials based on design equations for concrete and masonry walls

Abstract

Given that new construction materials are emerging but not yet recognized by the building code, it is of interest to develop a general method of generating capacity prediction for such new materials such as emerging fiber reinforced mixtures, hempcrete, 3D concrete printing (3DCP), and 3D clay printing based on design equations for the structural capacity of Reinforced Concrete (RC), Reinforced Masonry (RM), Unreinforced Masonry (URM), and Autoclaved Aerated Concrete (AAC). Many novel construction materials are not reflected in building codes, and/or American Society for Testing and Materials (ASTM) does not cover the relevant testing procedures. This paper reviews the processes that can lead to developing equations for conventional materials in order to propose a general procedure for emerging materials. The available experimental results are compared with predicted results based on design codes to study the accuracy of the equations. The study shows that the general procedure starts with solid mechanics equations and continues with an integrated procedure to convert the data from limited experiments to reliable design equations for new materials. Available procedures for RC, RM, URM, and AAC are reviewed and considered in the development of a general procedure. In the process, the effect of different parameters is discussed, and the effect of each parameter on the accuracy of the design equations is investigated. The effect of mechanical properties of the materials used, aspect ratio, thinness ratio, slenderness ratio, and reinforcement have been investigated on the strength of walls. The procedures and equations are compared to understand the main elements of the equations for new materials. For instance, the development of reinforced concrete walls started with ASD (allowable stress design) method with over-conservative equations. For decades, several studies have improved the predicted capacities to reach the experimental results considering safety. This study provides a comparison of capacity equations for RC, RM, URM, and AAC, and some general equations are proposed for novel materials.