The Research On Numerical Simulation Of Reinforced Concrete Masonry Walls With Block Element Method

Block Element Method (BEM) is proposed for numerical simulation on non-continuum problems. The Reinforced Concrete Masonry Walls(RCMW), composed of masonry, mortar, grouted concrete and reinforcements, could be regards macroscopically as non-continuum. The "block-seam-block" like modality of BEM would match the form "masonry-mortar-masonry" of RCMW geometrically. In addition, the block element is considered as rigid body, and its strength is greater than that of seam, which being treated as deformed body. This mechanic matching between BEM and RCMW, as well as their similarity in configuration, contribute to the application of BEM in numerical simulation on RCMW.The analysis is conducted in the plane-stress field, which needs the simplification of RCMW to plane-stress model. Both the effect of reinforcements and joint format of RCMW with other components should be taken into account before modeling. By adding the stiffness of reinforcement into the global stiffness matrix without expending its dimensions, the calculating model, that embedding the effect of reinforcement into block element effectively , was proved to be valid and reasonable via case studies. Also, the coupled-model of FEM and BEM, using transition seam, resolved the joint simulation between different components.After investing experimental results of masonry and mortar properties, it assumed that these materials behave as brittle stuff when rupturing, which led to applying the injury model to formulate their constitutive properties. Also, the cracking rule was specified on the basis this injury model. Accordingly, BEM home-code for RCMW cracking simulation was programmed via MATLAB.Based on the RCMW test of K.C.Voon, the BEM home-code was employed in simulating two walls-the one was reinforced with horizontal bar and the other not. The simulating results, showing the detailed cracking behaviors of walls under loading conditions, matched the test results, which verified the vidality and rationality of the simulation idea with BEM, as well as the BEM simulation home-code. Furthermore, the difference between walls with horizontal reinforcement and without, reported by code-based simulation, accorded with the test results.