ABSTRACT:

Large aggregate concrete is usually used in the mass offshore concrete structures. This paper presents the behavior of large aggregate concrete and sieved concretes under biaxial stress states. The tests are carried out on large size specimens of 25 × 25 × 40cm and 25 × 25 × 25cm and small size concrete specimens of 15 × 15 × 30cm and 15 × 15 ×15cm respectively. The specimens were subjected to biaxial load combinations covering the two regions of compression-compression and compression-tension. The test data indicated that the deformation and strength of the mass concrete specimens were lower than those of the corresponding wet-screened concrete small specimens, but the initial tangent modulus of the stress-strain curve for the former was larger than that for the latter. The test results showed that the size effect of the specimens under biaxial loading was important so that it should be considered in the design for the mass concrete structures. Based on the test data, failure criterion of mass concrete under biaxial loading was established and it could provide effective references for the design and safety evaluation of the massive coastal and offshore structures such as offshore platform and concrete dock wall in which the multiaxial strength of the concrete must be taken into consideration.

INTRODUCTION

For various purposes, in massive concrete structures such as concrete dams, water gates, docks, harbor constructions and nuclear power plants, large-sized coarse aggregates are used in the mix design of concrete (usually the maximum aggregate size reaches 80mm or more). Large coarse aggregates require less energy for size reduction with increased production rates. And they help to reduce thermal cracking and shrinkage during mass concrete curing. In practical engineering, these large concrete buildings are generally working under biaxial or triaxial stress state.

This content is only available via PDF.
You can access this article if you purchase or spend a download.