【摘要】 本工作创新性地将硅藻土进行预吸水处理,将其作为掺和料掺入高强混凝土中以解决高强混凝土易出现早期开裂的问题。试验研究了质量分数为1%、3%和5%的干燥硅藻土经过预吸水处理后对高强混凝土(混凝土等级C60)在特定状态下的早期抗裂性能和基本力学性能的影响,并结合水分蒸发试验,研究了掺入预吸水硅藻土后混凝土的失水规律。结果表明:与基准混凝土相比,预吸水硅藻土掺量为1%、3%和5%的高强混凝土的早期开裂面积分别减少31.8%、54.4%和65.8%,显著提高了高强混凝土的早期抗裂性能,同时降低了高强混凝土前期水分蒸发速率和质量损失,抑制其塑性收缩。另外,预吸水硅藻土的掺入对抗压强度未产生较大的负面影响,对劈裂抗拉强度与拉压比稍有提高。更多还原

【Abstract】 In this paper,the diatomite were wetted to be used as the admixture in high-strength concrete in order to solve its early cracking problem.The effect of pre-wetted diatomite(the mass fraction of dry diatomite are 1%,3%and 5%)on the early-age cracking resistance and the basic mechanical performance of high-strength concrete were studied.Water losing principle of the prewetted diatomite high-strength concrete was also tested by evaporation test.The results showed that the pre-wetted diatomite could significantly improve the early cracking resistance of the high-strength concrete.When the mass fraction of dry diatomite are 1%,3% and 5%,the early cracking area of concrete were reduced by 31.8%,54.4%and 65.8%.Meanwhile,the pre-wetted diatomite could significantly reduce the water losing of concrete,which inhibits plastic shrinkage.In addition,the incorporation of the pre-wetted diatomite could increases the tensile strength and the ratio of tension and compressive strength,and had no great negative effect on the compressive strength.更多还原