Experimental Research on Influence of Loading Method on Dynamic Behavior of Recycled Concrete

Abstract

The exploitation and application of recycled concrete are more and more extensive in latest years. But the research on the mechanics characteristic of recycle concrete under cyclic loading is very little. Six types of recycled concrete specimens were made in laboratory. After they were cured for a certain age, we have made a series of cycling loading tests on them. In the tests the maximum and minimal stress ratio, the loading frequency and loading waveform were all considered. The mechanics characteristic of recycled concrete under static loading and cyclic dynamic loading were contrasted. After analyzing the test results, we could get that the maximum stress and minimal stress ratio, the loading frequency and loading waveform influenced the unloading and loading modulus of recycled concrete directly in the tests, and the fatigue life of recycled concrete changed with the loading method.

Fatigue limit of recycled aggregate concrete

“…observed [13,[50][51][52]. In this case, the three stages representing approximately 15%, 70% and 15% of the total life time respectively unlike those observed by other authors [11,12]. The first stage A is similar to that observed one in concretes exceeding 2 •10 6 cycles.…”

“…Fatigue Behavior of Concrete with Recycled Concrete Aggregates" [10] in which the fatigue behavior of recycled concrete with different degrees of substitution and water/cement (w/c) ratios has been considered. Luo and Yao [11,12] have analyzed the deformation curves and the response to the ultrasonic pulses of recycled plain concrete subjected to low frequency fatigue and have confirmed the presence of three stages of behavior with a lifespan of 10%, 80% and 10% of the fatigue life, respectively. This effect is observed in non-recycled concrete specimens by Do et al [13].…”

Fast fatigue method for self-compacting recycled aggregate concrete characterization

“…Subsequently, these cracks begin to grow and interconnect until they reach a critical dimension that leads to failure (Carloni and Subramaniam, 2013). Regarding the fatigue behaviour of recycled concrete, although it is not a very developed topic, there are some works that indicate that the use of recycled concrete aggregates reduces the fatigue life, especially at replacements greater than 20% (Luo and Yao, 2011). determined that the loos in the fatigue limit due to the presence of recycled aggregates is higher than the reduction in the compressive strength.…”