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Cement and fly ash as a cementitious material with the straw fiber composite to get a certain strength and less dense composite lightweight insulation . This composite material based on the cementitious material is a continuous phase, straw fibers as a dispersed phase, made ??by vibrators molding . Specimen of physical properties, mechanical properties and thermal performance test system straw form of straw ash , fly ash material substitution rate the straw fiber pretreatment, conservation and molding methods , and other factors on a cement base straw properties of fibrous material . First study the impact of different mass fractions of sodium hydroxide solution , soaking time and morphology of straw straw fiber quality loss , facilitate straw fiber in cement-based composite applications ; Secondly, the study straw morphology , straw ash , fly ash material replacement rate and conservation of the physical properties of the straw fiber cement-based materials , mechanical properties, thermal properties of the impact of the law , to determine prepared necessary for testing the the straw fiber length range , the best content of the straw fiber , fly ash the best replacement rate , the best conservation methods and molding way ; then followed by fiber research pretreated straw straw straw fiber cement-based fiber materials investigated , and finally , according to the results of the scanning electron microscope , the paper discusses the chemical composition of the straw investigated and the mechanism of action of different scales and incorporation of plant fiber formation process of setting and hardening process of cement hydration products , microstructure , cement - straw interfacial adhesion . The test results showed that the straw fibers in the mass fraction of 4% NaOH solution for 12 hours , the basic mass loss of the straw fibers have reached the maximum value ; compared to the coefficient of thermal conductivity of the fine straw fiber prepared CSF compared with coarse straw fiber prepared CSF low; when the straw fiber content is 20% , CSF thermal conductivity of 0.117W / m · k; replace the rate of 50% fly ash material , the CSF early strength decreased ; alkali treatment and sodium silicate the straw fibers can be coated effectively improve the strength of the CSF substrate ; through the observed on CSF scanning electron microscope pictures , an alkali treatment and sodium silicate coated straw fibers can effectively improve the adhesion of the straw fibers and cement stone , improved straw fiber and cement paste interface structure .
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