Experimental Research On The Mechanical Properties Of Recycled Concrete And The Bending Performance Of Beams

This thesis researched the influences of using replacement of natural aggregate with recycled concrete, fly ash and slag on the mechanics capacity of recycled concrete through experiments, as well as analyzed the working mechanism of recycled concrete. based on the analysis of plentiful standardized test block experiment results, the author selected several scenarios, poured recycled concrete beam, researched the influences on the bending performance of recycled concrete beam of different replacement of natural aggregates and additives. From the analyses of the test result get some conclusions as follow:1) When compare with concrete, the mechanical property of recycled concrete is low. When the replacement of natural aggregate with recycled concrete reaches 30%, with the increasing of replacement of natural aggregate with recycled concrete, the property of recycled concrete became lower and lower. If use fly ash to replace cement equate, with the increasing of fly ash quantity, the mechanical properties of recycled concrete declined. If use fly ash and slag to replace concrete together, the effect is better.2) There are no clear distinctions between the bending performance of recycled concrete beam and concrete beam. The strain measured on cross-section of recycled concrete beam still obliges to the plane section assumption better. When compare with concrete beam, the cracking strength of recycled concrete beam is low. With the increasing of replacement of natural aggregate with recycled concrete. The destroy strength of recycled concrete beam become lower and lower.3) There are both technical and economic possibilities of recycled concrete, the cost of miniature recycled concrete projects is high, however, from the point of environmental protection and sustainable development, recycled concrete has its unique advantages. The promotion of recycled concrete needs government's policy supports.