Multiaxial Failure Criterion Of Concrete In Freeze-Thaw Cycling Environment

Experimental investigation on multiaxial failure criterion of concrete in freeze-thaw cycling environment is just in initial stages, and the literature in this field is scarce. As a part of the project of science foundation "Research on failure criterion and durability of concrete in severe environments" (2023901023) of educational department of Liao Ning province, 127 specimens' experiments on unaxial compression, unaxia tension, biaxial compression, biaxial compression-tension and triaxial compression under proportional stresses of normal concrete whose strength degree is C30 after different cycles of freeze-thaw cycling were made. Based on the comparison between experimental results of specimens after freeze-thaw cycling and that in normal environment, multiaxial failure criterion of concrete after freeze-thaw cycling is established. Main researchful contents in this paper are as follows:1. Freeze-thaw cycling experiments of Concrete specimens 100 100 100mm3 were made, cycles of freeze-thaw cycling include 25, 50, 75 and 100. Weight loss and dynamic elastic moduli are measured.2. Multiaxial Proportional loading experiments of concrete specimens under normal environment and after freeze-thaw cycling were made using triaxial test system for concrete. Deformation measure methods are analysed.3. Failure forms of common concrete under biaxial compression, biaxial tension-compression and triaxial compression after freeze-thaw cycling are analyzed, and comparison of failure form with concrete in normal environment under same loading condition are made.4. Affection of cycles of freeze-thaw cycling, stress ratio on strength, strain of concrete are studied. Based on regression of experimental results, failure criterions of concrete under biaxial compression,biaxial tension-compression and triaxial compression after freeze-thaw cycling are established.