Experimental Study On The Shear Behavior Of Recycled Concrete With Artificial Sand

The tremendous ecological pressure which caused by excessive consumption of natural aggregate and construction waste have to be the major global problems. In order to solve the problems, researches on recycling aggregate concrete are studied by many scholars at home and abroad. The researches have obtained important achievement, some of which have widely applied in the practical engineering and played a positive role in protecting ecological environment and conserving ecological resources. Therefore, the research on recycled aggregate concrete have been become an important subject in the future. Based on learning the mature theories and test results of recycled concrete, our g roup have been carrying out some researches on recycled concrete with artificial sand.The recycled concrete with artificial sand researched in this paper is a new style construction material which designed in a certain mix proportion to the fine aggregate and coarse aggregate. The fine aggregate is made by using the artificial sand crushed from limestone waste, and the coarse aggregate is made by the materials crushed from the waste expressway pavement concrete. On the basis of our group’s test results of the physical and mechanical properties of recycled concrete with artificial sand and understanding the domestic’s dynamic about the recycled concrete mechanical properties, the experimental research which is carried out by four-point static loading test on shear performance of recycled concrete with artificial sand is carried on in this paper. Considering two strength grades (C35, C45) and the different artificial sand replacement rate (0%、30%、50%、70%、100%) as variables factors, thirty-six uniform depth beams are designed in the experimental.The main conclusions for the test study can be drawn as follows:1) The recycled concrete with artificial sand could have the comparative workability with the natural concrete.2) With the same water-cement ratio, cubic compressive strength of the recycled concrete with artificial sand is higher than that of the natural concrete’s. The higher amplitudes range between7%and20%. 3) The replacement percentage of artificial sand has a certain influence to the cube compressive strength. Artificial sand replacement ratio which range of30%to70%in has made the cube compressive strength more lower than other situations.4) The recycled concrete with artificial sand’s shear destruction is a typical brittle fracture. Fracture surface is basically flat, including the old and new mortar joint surface splitting and internal cross-section from the coarse aggregate particles.5) The shear strength and peak strain of the recycled concrete with artificial sand raised with the increase of the cubic compressive strength, but the values are lower than the nature ones. The decreasing Value of shear strength is between13.1%-20.1%.6) The shear stress and shear strain curves of the recycled concrete with artificial sand are similar to the results of nature concrete, but the slope of the curves is lower than it in the nature concrete. The values of peak shear strain are generally from300to450us. And the calculation formula for stress-strain curve are proposed on the basis of test results.7) The recycled concrete with artificial sand’s shear modulus is lower than the natural concrete.