【作者】 王明江；

【导师】 杨英姿；

【作者基本信息】 哈尔滨工业大学 ， 建筑与土木工程， 2012， 硕士

【摘要】 稻壳/稻草是农业废弃物，占用空间、破坏环境。将其应用于建筑材料行业，将会带来巨大的经济和环境效益。本课题研制了一种用稻壳、石屑、粉煤灰等工农业废料结合少量水泥制作的水泥基材料用做新型轻质水泥基材料。本文的主要研究内容是稻壳掺量、稻壳预处理方式、制作工艺等对稻壳水泥基材料(Cement-based Rice Husk Materials简称CRHM)物理力学性能和耐久性能的影响，稻草制作的水泥基材料(Cement-based Straw Fibers Materials简称CSFM)的性能以及CRHW的几种性能改善方案。研究表明：稻壳质量掺量在0~8%逐渐增加时：CRHM的抗压强度下降88.6%，体积密度下降33.5%，稻壳质量掺量4%时的试件28d抗压强度12.7MPa，体积密度1618kg/m~3，较为理想。随着稻壳掺量的增加，CRHM冻融试验质量损失，强度损失逐渐变大，50次冻融后最大质量损失4.8%，最大强度损失27.5%，掺量8%的CRHM抗冻标号D25，掺量0~6%的CRHM抗冻标号为D50；CRHM收缩率随稻壳掺量增加而减小，28d时，未掺稻壳试样收缩率为467微应变，而质量掺量8%的试件为220微应变。抗碳化性随着稻壳掺量增加逐渐减弱，由于CRHM的疏松多孔，稻壳掺量8%的试件在14d时碳化深度就已经达到了100mm。CRHM软化系数随着稻壳掺量增加逐渐降低，但均在0.75以上。其中稻壳质量掺量3%的试件软化系数0.95，耐水性能良好。比较5种稻壳预处理方式，“表面喷水，陈化12h”对提高CRHM抗压强度效果最好，“表面喷有机硅烷水溶液，60℃烘干”对提高CRHM抗冻性效果最好。保持水灰比0.5制作水泥基稻草纤维材料，当稻草质量掺量超过(占水泥质量)5%以上时，出现凝结困难或者不凝现象。稻草纤维3种预处理方式中NaOH溶液处理对提高CSFM抗压强度效果最好。质量掺量相同时，稻壳比稻草更能降低试件体积密度、提高试件抗压强度，二者体积密度最大相差11.3%，抗压强度最大相差5.8倍。硫铝酸盐水泥CRHM强度增长快，1d就可以达到28d强度的87%，但不宜用蒸汽养护，蒸汽养护3d强度比标准养护28d强度小33.8%。蒸汽养护有利于普通硅酸盐水泥制备的CRHM强度增长。河砂等量取代石屑制作CRHM，体积密度与抗压强度变化不大。用煤矸石取代石屑制作CRHM，体积密度增加6.4%、抗压强度提高30.0%。将实验室获得配合比进行工厂试制，依据GB/T15229-2002《轻集料混凝土小型空心砌块》的相关规定，利用稻壳水泥基材料可制成体积密度800级~900级、抗压强度均满足MU5.0的空心砌块。更多还原

【Abstract】 Rice husk/Rice straw is a series of agricultural waste, which takes up the cultivatedland and contaminates the environment. Its application in building materials industrywill bring huge economic and environmental benefits. This paper will focus on a kind ofcement-based material used as new light-weight wall materials by applying rice husk,stone flocks, fly ash and a certain amount of cement.The main research contents are that the effects of the dosage of rice husk,pretreatment methods, manufacture technology on the physical and mechanicalperformance and durability of Cement-based Rice Husk Materials (referred to CRHM),and the performance and preparation of Cement-based Straw Fibers Materials(referredto CSFM), as well as the optimization design of CRHW.The experimental results showed that with the dosage of rice husk increased from0to8%, the compressive strength of CRHM reduced88.6%and the volume densitydecreased33.5%. The better mix proportion was with of4%rice husk content, and itscompressive strength at28d reached12.7MPa with the volume density of1617.5kg/m~3.Along with the increase of the rice husk dosage, the mass loss and strength loss ofCRHM were getting bigger after freeze-thaw cycles. The largest mass loss was4.8%and the biggest strength loss was27.5%after50freeze-thaw cycles. The frost resistancegrade of CRHM with of8%rice husk was D25, and the others were D50. The shrinkagerate of reduced with the rice husk dosage increased. At28d, the shrinkage rate of theCRHM without rice husk was467micro strain and the CRHM with rice husk of8%was only220micro strain. The carbonation resistance of CRHM was getting weakerwith the increase of rice husk dosage, because the looser porous structure of CRHM.For example, the carbonation depth with8%of rice husk in14d had reached100mm.The softening coefficient of CRHM gradually decreased with the dosage of rice huskincreased, but all of them were more than0.75. Especially, the softening coefficientCRHM with3%rice husk reached0.95.Compared5kinds of rice pretreatment method,"surface water spray,12h" was thebest way to improve compressive strength of CRHM and "spray organic silane solution,60℃drying" was the best way to improve frost resistance of CRHM.Keep the water cement ratio equaled0.5, the cement base straw fiber materialswere difficult to set and harden when the straw fiber content was more than5%(of thequality of the cement). Of three pretreatment methods for straw fibers, the NaOHsolution processing was the best way to improve the compressive strength of CSFM.When the content of rice husk and straw fiber kept constant, the rice husk could easilyreduce volume density and improve the compressive strength. Even both the volume density showed a little difference, however, the compressive strength of the biggestdifference was5.8times.The sulphoaluminate cement increased the strength of CRHM quickly, whosestrength at1d can reach87%of the28d strength, but it is not suitable for steam curingbecause the3d strength for steam curing is smaller33.8%than that of standard curing at28d. Steam curing was better for the strength growth of CRHM with ordinary Portlandcement. Sand may substitute the crumbs for the production of CRHM. Replaced stonechips made by coal gangue CRHM, the volume density will increases by6.4%and thecompressive strength will increase by30.0%.After the factory testing, according to GB/T15229-2002"Standard for smallhollow blocks of lightweight aggregate concrete ", the rice husk/straw fiber cement basematerials can produce the hollow blocks with volume density level of800~900grade,compressive strength of MU5.0.更多还原