不同再生粗集料混凝土单轴受压应力-应变全曲线

Complete Stress-Strain Curve of Concrete with Different Recycled Coarse Aggregates under Uniaxial Compression

用原始强度等级分别为C20和C50的废混凝土制作了再生粗集料,再将再生粗集料以不同的比例混合,然后采用相同的配合比制作棱柱体混凝土试件,并在电液伺服试验机上测定其单轴受压应力-应变全曲线.结果表明:当再生粗集料不同时,再生混凝土单轴受压应力-应变全曲线之间离散较大,轴心抗压强度明显降低,而弹性模量则受控于废混凝土强度等级较低的再生粗集料.

Two kinds of waste concrete, C20 and C50, were crushed as recycled coarse aggregates and mixed at different ratios to simulate recycled coarse aggregates from different origins. Prisms （100 mm×100 mm×300 mm） were cast with the same mix proportion and the complete stress-strain curves under uniaxial compression were obtained using an electro-hydraulic servo test machine. It can be found from the stress-strain curves that when different recycled aggregates are mixed, the diversity of stress-strain curves becomes greater. Meanwhile, the axial compressive strength decreases, and the elastic modulus is controlled by the coarse aggregate with lower original concrete strength grade.