RAPC抗压强度离散性与骨料关系试验研究

Experimental Study on Dispersion of Compressive Strength of Recycled Aggregate Permeable Concrete

骨料是影响再生骨料透水混凝土(Recycled Aggregate Permeable Concrete,RAPC)强度离散性的关键之一。对不同强度不同来源的再生骨料,设计试验研究RAPC的抗压强度特征和抗压强度离散性。结果表明:RAPC的离散性表现明显,原混凝土强度等级越高,再生骨料的基本物理性能越好,抗压强度与之正相关,抗压强度离散性与之反相关。建筑垃圾回收厂的再生骨料制作的离散性更大。因此回收利用再生混凝土骨料时,有必要根据其强度等级进行分类回收,最大限度地发挥RAPC的性能。

At present,due to the different sources and uneven quality of recycled aggregates,the performance of RAPC is severely restricted,and the popularization and application of RAPC pavement is limited.To solve this problem,four kinds of waste concrete with different strength grades were used to prepare recycled aggregates,and recycled aggregates from different sources were used to prepare recycled aggregate permeable concrete,and the influence of aggregate sources on the compressive strength and dispersion of compressive strength of RAPC was studied.The results show that:the higher the strength grade of native concrete,the better the basic physical properties of recycled aggregate,showing higher apparent density and close packing density,lower water absorption and crushing index;the strength of native concrete is related to the RAPC resistance.The compressive strength is positively correlated,and the compressive strength of RAPC can be increased by about 10%for every 10 MPa increase in the strength of the original concrete;the discreteness of the compressive strength of RAPC prepared from recycled aggregates with determined sources is much lower than that of recycled bone produced by construction waste crushing plants RAPC prepared with raw materials,and the higher the strength of the original concrete,the better the discreteness of the compressive strength of RAPC.Therefore,when recycling recycled concrete aggregate,it is necessary to classify and recycle according to its strength level to maximize the performance of RAPC.