纳米CaCO3和PVA纤维增强混凝土工作性及力学性能的研究

基于坍落度、坍落扩展度、抗压强度和抗压弹性模量试验,研究了体积掺量分别为0.05%、0.1%、0.15%、0.2%的PVA纤维和质量掺量分别为1%、2%、3%、4%的纳米CaCO3颗粒对掺粉煤灰混凝土工作性和力学性能的影响。结果表明,在一定的掺量范围内,随着纳米CaCO3掺量的增加,混凝土的抗压强度和抗压弹性模量先增大后减小,当纳米CaCO3掺量为3%时,抗压强度和抗压弹性模量达到最大值;随着PVA纤维体积掺量的增加,混凝土抗压强度先增大后减小,而抗压弹性模量整体上呈逐渐减小的趋势,当纤维体积掺量为0.15%和0.05%时,抗压强度和抗压弹性模量分别达到最大值;新拌混凝土的工作性随着纳米CaCO3和PVA纤维掺量的增加而逐渐降低。

Study on the Workability and Mechanical Properties of Nano-CaCO3 and PVA Fiber Reinforced Concrete

The slump,slump spread,compressive strength and compressive elastic modulus tests were carried out,and the effects of PVA fiber with volume content of 0.05%,0.1%,0.15%,and 0.2%and nano-CaCO3 particles with mass content of 1%,2%,3%,and 4%on the workability and mechanical properties of fly ash concrete were studied.The results show that the compressive strength and compressive elastic modulus of concrete increase first and then decrease with the increase of nano-CaCO3 content within a certain range,and when the nano-CaCO3 content is 3%,the compressive strength and compressive elastic modulus can reach the maximum.The compressive strength increases first and then decreases with the increase of PVA fiber content,while the compressive elastic modulus decreases gradually as a whole,and when the content of PVA fiber are 0.15%and 0.05%,the compressive strength and compressive elastic modulus reach the maximum.The workability of fresh concrete gradually decreases with the increase of nano-CaCO3 and PVA fiber content.