Mechanical and Failure Criteria of Air-Entrained Concrete under Triaxial Compression Load after Rapid Freeze-Thaw Cycles

Feng-Kun Cui,Guo-Sheng Ren,Guo-Xi Fan,Tie-Jun Zhao,Huai-Shuai Shang

doi:10.1155/2017/6786270

Abstract

The experiment study on the air-entrained concrete of 100 mm cubes under triaxial compression with different intermediate stress ratioα2=σ2D : σ3Dwas carried out using a hydraulic-servo testing system. The influence of rapid freeze-thaw cycles and intermediate stress ratio on the triaxial compressive strengthσ3Dwas analyzed according to the experimental results, respectively. The experimental results of air-entrained concrete obtained from the study in this paper and the triaxial compression experimental results of plain concrete got through the same triaxial-testing-system were compared and analyzed. The conclusion was that the triaxial compressive strength is greater than the biaxial and uniaxial compressive strength after the same rapid freeze-thaw cycles, and the increased percentage of triaxial compressive strength over biaxial compressive strength or uniaxial compressive strength is dependent on the middle stress. The experimental data is useful for precise analysis of concrete member or concrete structure under the action complex stress state.

Highlights

In cold regions, such as northern China, Russia, Canada, and northern Europe, the performance deterioration of concrete applied in practical engineering can be caused by the action of rapid freeze-thaw cycles
After the action of 200 rapid freeze-thaw cycles, the uniaxial compression strength and biaxial equal compression strength decreased to 81.0 and 83.1 percent of those prior to the rapid freezethaw cycles, respectively; under the action of triaxial compression with stress ratio α = 0.10 : 1.00 : 1.00, the strength decreased to 86.05 percent of that prior to the rapid freeze-thaw cycles
The triaxial compression strength and biaxial compression strength of air-entrained concrete are higher than uniaxial compression strength, and the triaxial compression strength is higher than biaxial compression strength due to the fact that there are inhibitory effect in the direction of σ1D and σ2D

Summary

Introduction

In cold regions, such as northern China, Russia, Canada, and northern Europe, the performance (e.g., strength, deformation and elasticity modulus) deterioration of concrete applied in practical engineering can be caused by the action of rapid freeze-thaw cycles. Ozgan and Serin [1] investigated the effect of freeze-thaw cycles on asphalt concrete materials according to Marshall stability values and ultrasonic velocity and so forth. The value of fracture parameters of lightweight concrete after different freeze-thaw cycles was determined through a three-point bending test in [2]. The weight loss, pulse velocity, and resonance frequency of silica fume concrete after the action of freeze-thaw cycles were reported in [3]. The influence of freeze-thaw cycles on the behavior (compressive strength, weight loss, and relative pulse velocity) of concrete with synthetic fibre additions was studied in [4]. The experimental results show that the freeze-thaw cycles can cause the degradation of the strength and deformation properties of asphalt concrete, lightweight aggregate concrete, silica fume concrete, and so forth

Results

Discussion

Conclusion