【摘要】 采用平板试验(包括分形维数分析)研究了橡胶砂浆的塑性收缩开裂性能,同时,采用ACI-544推荐的落锤法,研究了橡胶混凝土的抗冲击性能。结果表明,用橡胶颗粒等体积取代25%的砂,能有效抑制裂缝的产生和扩展,显著提高砂浆抵抗塑性收缩开裂的能力。此外,橡胶颗粒等体积取代25%的砂后,虽然混凝土抗压强度较素混凝土下降了34%,但其抗冲击次数却提高了6.2倍。复合掺加橡胶颗粒和1kg/m3的高弹性模量PVA纤维后,混凝土抗冲击次数是素混凝土的8.3倍,为单掺橡胶混凝土的1.3倍。更多还原

【Abstract】 The early-age plastic shrinkage and cracking resistance of rubber particles modified mortar are investigated by using slab tests with fractal theory and the influence of rubber particles on impact performance of concrete is also studied by hammer-drop tests.The results show that the rubber particles can restrain the occuring and propagating of the plastic shrinkage cracks of mortars,and the impact property is improved obviously due to the addition of rubber particles included in concrete.Rubber included concrete can resist 6.2 times higher impact attack than reference concrete although its compressive strength is 34% lower than reference concrete.Furthermore,when high elastic modulus PVA fibers are added in to concrete together with rubber particles,the concrete can undertake 8.3 times higher impact attack than reference concrete,that is 1.3 times higher than that of only adding the rubber particles.更多还原