基于响应面法的碱激发地聚物固化淤泥质土试验研究  

Experimental Study of Alkali-Activated Geopolymer Cured Silty Soil Based on Response Surface Method

作　　者：李胜 张红日 王桂尧[1] 邓人睿 LI Sheng;ZHANG Hongri;WANG Guiyao;DENG Renrui(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,China;Guangxi Transportation Science and Technology Group Co.,Ltd.,Nanning 530007,China)

机构地区：[1]长沙理工大学土木工程学院,长沙410114 [2]广西交科集团有限公司,南宁530007

出　　处：《硅酸盐通报》2023年第12期4438-4448,共11页Bulletin of the Chinese Ceramic Society

基　　金：桂西南地区特殊土联合实验室资助(崇科2023ZY0504);交通运输部2022年度交通运输行业重点科技项目(2022-MS5-125)。

摘　　要：为实现滩涂淤泥质土和工业废料资源化利用,定量优化地聚物固化淤泥质土的关键因素,基于Box-Behnken响应面法对碱激发矿渣-粉煤灰基地聚物固化淤泥质土的配合比进行优化,选取矿渣掺量、碱激发剂模数和碱激发剂掺量为主要考察因素,并结合宏观性能和微观形貌进行固化机理分析。结果表明:固化土最优配合比为矿渣掺量86.5%(质量分数),碱激发剂模数0.84,碱激发剂掺量7.3%(质量分数),此时固化土7和28 d无侧限抗压强度分别为5823和7027 kPa,预测值与实际值误差较小,所建立的模型与实际数据拟合准确可靠;固化土的水化产物主要为无定形凝胶水化硅铝酸钙(C-(A)-S-H)和硅铝酸盐聚合物(N-A-S-H),可增强土体的密实程度和骨架结构,以此提高固化土的强度。本研究为碱激发地聚物固化淤泥质土提供了理论依据和实验基础。In order to achieve the resource utilization of beach silty soil and industrial wastes,and quantitatively optimize the critical factors of geopolymer cured silty soil,the mix ratio of alkali-activated slag-fly ash based geopolymer cured silty soil was optimized based on the Box-Behnken response surface method.The slag content,alkali activator modulus and alkali activator content were selected as the main factors to be investigated,and the curing mechanism was analyzed by combining the macroscopic properties and microscopic morphology.The results show that:the optimum mix ratio of cured soil is slag content 86.5%(mass fraction),alkali activator modulus 0.84,alkali activator content 7.3%(mass fraction),the unconfined compressive strength of cured soil at 7 and 28 d under the optimum mix ratio is 5823 and 7027 kPa,respectively.The prediction value has a small error with the actual value,and the established model is accurate and reliable in fitting the actual data.The hydration products of cured soil are mainly amorphous gel hydrated calcium silica-aluminate(C-(A)-S-H)and silica-aluminate polymer(N-A-S-H),which enhance the densification and skeletal structure of soil body,thus improving the strength of cured soil.This study provides a theoretical basis and experimental foundation for alkali-activated geopolymer cured silty soil.

关 键 词：响应面法 碱激发 地聚物 淤泥质土 优化 无侧限抗压强度 微观结构 

分 类 号：TU52[建筑科学—建筑技术科学]