RANDOM AGGREGATE MODEL OF THREE-GRADING CONCRETE AND ITS APPLICATION

摘要

A practical method is presented for modeling of two-dimensional arbitrary aggregate shape, which is the key point of the numerical concrete simulations. An efficient algorithm is developed on the basis of considering the characteristic of mass concrete with high aggregate content ratio (0. 6 — 0. 7). All the same kind of random triangle fundamental aggregates are generated at one time, and then the two dimensional arbitrary shapes of aggregate can be generated by the method of random extension. The presented algorithm is superior to the common method, in which all aggregates are put one by one, and the former algorithm avoids the defects of the latter algorithm, such defects are as follows: inefficiency of algorithm, low aggregate content etc. Corresponding software 2D - RAS is developed on the basis of this algorithm. And with this software, the behavior of the three-grading concrete specimen under uniaxial tension is studied. The results indicate critical load capacity of the specimen with the random arbitrary shape aggregate is greater than that of the specimen with random circle aggregate. The number of cracks of the specimen with random arbitrary shape aggregate is less than that of the specimen j with circle aggregate.