废弃橡胶混凝土的力学性能和断裂韧性及抗冻性能

Mechanical properties, fracture toughness and frost resistance of waste rubber concrete

以废弃轮胎加工产生的橡胶颗粒为原材料,研究了废弃橡胶混凝土的力学性能、断裂韧性和抗冻性能。结果表明,掺加橡胶后,混凝土的抗压强度、拉伸强度和弹性模量均低于基准混凝土,且随着橡胶取代率的增加而逐渐下降,掺入粒径为2~4 mm的橡胶时,橡胶混凝土的抗压强度、拉伸强度均达到最大。橡胶颗粒的存在能够缓解裂缝尖端的应力集中,延缓橡胶混凝土试件裂缝的产生及发展,有利于增强橡胶混凝土的断裂韧性。在混凝土中掺入适量的橡胶有利于提高橡胶混凝土的抗冻性能,当橡胶取代率为5%时,冻融循环后橡胶混凝土的相对抗压强度最高。

The mechanical properties, fracture toughness and frost resistance of waste rubber concrete were studied with rubber particles produced by waste tire processing as raw materials. The results showed that after adding rubber, the compressive strength, tensile strength and elastic modulus of concrete were lower than those of reference concrete, and gradually decreased with the increase of rubber replacement ratio. When adding rubber with particle size of 2-4 mm, the compressive strength and tensile strength of rubber concrete reached the maximum.The existence of rubber particles could alleviate the stress concentration at the crack tip, delay the generation and development of cracks in rubber concrete components, and helpe to enhance the fracture toughness of rubber concrete.Adding appropriate amount of rubber in concrete was beneficial to improve the frost resistance of rubber concrete. When the rubber replacement ratio was 5%, the re-lative compressive strength of rubber concrete after freeze-thaw cycle was the highest.