Experimental Study on CaCO_3 Whisker-reinforced Fiber Cement Mortar

摘要

As a kind of monocrystal reinforcing material, CaCO_3 whisker has good characteristics of high strength, high module and high thermal stability. This research aims to optimize the microscopic structure of fiber cement mortar by adding CaCO_3 whiskers and improve the macroscopic mechanical properties. The results showed that CaCO_3 whiskers increased the flexural and compressive strength of cement mortar at 3d age by 29.5% and 19.8% at maximum respectively, which fell to 7.2% and 13.0% at 28d age; when CaCO_3 whiskers content was 10% and polypropylene fibers content was 0.05%, compared with the pure cement mortar, the fiexural and compressive strength were increased by 32.4% and 29.4% at 3d age and 7.6% and 4.6% at 28d age respectively; when the fiber length was 9mm, the composite effect of whiskers and fibers was more ideal; through the SEM analysis, the reinforcing mechanisms of CaCO_3 whiskers and polypropylene fibers in cement mortar were discussed.