Abstract:

In this paper,three kinds of organic lightweight aggregate concrete,whose coarse aggregate was partially substituted respectively by virgin expanded polystyrene ( EPS) beads,recycled EPS beads and waste rubber particles,respectively,were prepared,and the failure mode,elastic modulus and complete stress-strain curve of the concrete under uniaxial loading were investigated. Moreover,the complete stress-strain curves of the organic lightweight aggregate concrete were fitted by using different formulas. The results illustrate that the complete stress-strain curves of the organic lightweight aggregate concrete are all similar to those of the ordinary concrete,while the feature points on the curves are significantly different from those of the ordinary concrete,that the elastic modulus and peak stress of the concrete are remarkably lower than those of the control concrete,that the elastic modulus of the recycled EPS concrete is similar to that of the virgin EPS concrete,that rubber concrete is of the lowest elastic modulus and peak stress but it is of the highest ratio of peak elastic modulus to peak stress,that the elastic modulus,peak strain and peak stress of EPS concrete all decrease with the increase in EPS dosage,and the complete stressstrain curves of the three kinds of concrete fitted with different formulas all accord well with those obtained by experiments,with the correlation coefficient being more than 93%.

Key words: lightweight aggregate concrete, expanded polystyrene, rubber bead, elastic modulus, complete stressstrain curve