稻壳灰对水泥基材料力学性能的影响研究

Effect of rice husk ash on mechanical properties of cement-based materials

为了研究稻壳灰对水泥基材料力学性能和抗冻融性能的影响,在不同稻壳灰掺量、不同龄期以及不同冻融循环次数等因素影响下开展了基本力学性能试验和冻融循环试验的研究,运用SPSS软件建立了冻融循环试验后掺入稻壳灰的水泥基材料抗压强度的多元线性回归方程,并通过SEM试验揭示了稻壳灰对水泥基材料的抗冻融性能的影响机理。结果表明:稻壳灰掺量在一定范围内,水泥基材料的强度与稻壳灰掺量成正比例关系;养护龄期28 d、稻壳灰掺量7%水泥基材料的抗折和抗压强度与基准组相比分别提高了44.1%、74.4%;随着冻融循环试验次数的增加,稻壳灰水泥基材料的抗折和抗压强度降低速率与基准组相比较为缓慢;SEM试验结构表明水泥基材料在冻融循环作用下,稻壳灰可有效提高水泥基材料的抗冻融性能。

In order to study the effect of rice husk ash on the mechanical properties and freeze-thaw resistance of cement-based materials,the basic mechanical properties and freeze-thaw cycle tests were carried out under the influence of different rice husk ash content,different age and different freeze-thaw cycle times,The multiple linear regression equation of compressive strength of cement-based materials mixed with rice husk ash after freeze-thaw cycle test is established by SPSS software,and the influence mechanism of rice husk ash on the freeze-thaw resistance of cement-based materials is revealed by SEM test.The results show that the strength of cement-based materials is directly proportional to the content of rice husk ash in a certain range.Compared with the reference group,the flexural and compressive strength of cement-based materials with curing age of 28 days and rice husk ash content of 7%were increased by 44.1%and 74.4%respectively.With the increase of freeze-thaw cycle test times,the reduction rate of flexural and compressive strength of rice husk ash cement-based materials is slow compared with the reference group.SEM test structure shows that rice husk ash can effectively improve the freeze-thaw resistance of cement-based materials under the action of freeze-thaw cycle.