Automatic Generation Of Mesostructure Of Concrete

Nowadays, research on mechanical behavior of concrete is based on experiment, which takes plenty of manpower and material resources, and test results obtained from the experiments is largely discrete because of experimental conditions, circumstance and complexity of material itself etc. In this case, numerical simulation in mesolevel, which combine experiment and theory together, is an effective way of researching concrete.From the point of concrete material, complying with the idea of software engineering, based on data structure and computer graphics, the mesostructure of concrete is automatic generated with MATLAB. The main content includes: automatic generation and optimization of 2-D concrete mesostructure, automatic generation of 3-D concrete mesostructure.In meso-level, concrete is taken as complex multiphase inhomogeneous material consists of aggregate, mortar matrix and the interface zone between them. Several achievements are gained. Firstly, polygon aggregate with random shape is generated by altering the polar radius and polar angle in polar coordinates. According to grain gradation and Walraven formula, the number of aggregate in every intercom can be calculated. Planar numerical concrete mesostructure is founded through distributing randomly aggregates from large to small. Optimization on 2-D mesostructure of concrete has been done which includes spiculate and flaky judgment, overlap judgment, statistics of coordination number and so on. Secondly, algorithm is improved in the sense of efficiency, which contains optimization of aggregate distribution and precisely meets of grain gradation. Quality evaluation of mesostructure of concrete is done. At last, in spherical coordinates, generation algorithm of convex polyhedron is erected through choosing randomly several points on the surface of the ellipsoid as the vertexes of the convex polyhedron. 3-D concrete mesostructure is successfully obtained through distributing randomly aggregates while aggregate location conflicts and overlaps are eliminated with conflicting and overlapping criteria in the algorithm. Example shows mesostructure of concrete simulates accurately the real concrete.