天然树脂对混凝土抗冻性能的影响与机理

Effect of natural resin on frost resistance and mechanism of concrete

研究了分别掺质量分数为0％，0．1％，0．5％，1％，2％的天然树脂（NR）对混凝土抗冻性影响，探讨了天然树脂（NR）改善混凝土抗冻性的作用机理，并建立了相应的理论模型．结果表明：不同掺量的天然树脂（NR）可提高冻融后混凝土的抗压强度20％～50％左右，而且使冻融后混凝土的弹模显著提高，一般为空白混凝土的3．76～5．64倍．同时表面微观结构、MIP及NR溶液负温性能研究表明：NR改善混凝土抗冻性的机理在于有效廷缓混凝土孔溶液的热质交换与传递过程，使混凝土孔隙溶液达到冰点的时间后移，提高混凝土冻融循环后的结构稳定性．

Effects of natural resin（NR） on the frost resistance of concrete with the frost resistance containing 0% , 0. 1%, 0. 5% , 1%, and 2% NR were investigated, and the frost mechanism and model of concrete with NR were explored. Results indicate that compressive strength of concrete after the freeze and thaw test with NR increases 20% - 50% and elastic modulus also increases remarkably, which is 3.76 - 5.64 times more than that of the control concrete. At the same time, the results of MIP and the minus-temperature property of NR solution indicate that the frost resistance of concrete with NR can be improved due to delaying the exchange and transfer in the pore solution concrete, which results in the delay of the time when pore solution reaches to freezing point and improving the structure stability of concrete after the freezing and thaw process.