现有岩土体微细结构试验方法均存在不足和弱点，要更深入的揭示岩土材料的力学行为和工程现象本质，开拓新的测试手段和分析方法是必要的。节约不可再生资源、减少对环境影响的新型岩土材料气泡混合轻质土，在作为路堤填料时，其耐久性一直为人们所担忧，亟待深入研究和探索。本项目拟在构建新试验手段的基础上，开展气泡混合轻质土耐久性方面的研究。主要内容：⑴研制光学测试与Micro-CT测试双模态融合的岩土三维微细结构演化分析试验系统；⑵借助微细结构试验研究，分析气泡混合轻质土在初始损伤及车辆动载、干湿循环、化学侵蚀不利因素作用下微细结构的变化规律，揭示耐久性劣变规律与损伤机理；⑶借助损伤理论等，研究能描述气泡混合轻质土初始损伤和在各种工况下耐久性劣变过程的损伤量，建立含微细结构变化特征参数的损伤演化方程。研究成果不仅有利于新型岩土材料安全、科学的推广应用，而且对我国岩土微细结构试验技术的发展也有较大的促进作用。

Due to the deficiency of current micro-structure test methods of rock and soil, it is necessary to explore new test means and analysis ways in order to further reveal the nature of mechanical behavior and engineering phenomenon of geotechnical material. New geotechnical material such as Foamed Mixture Lightweight Soil(FMLS) , which can save non-renewable resources and reduce effects on environment, when used in embankment filling, of which durability has caused people’s concerns and needs to be studied and explored deeply. This project intends to carry out researches on the durability of FMLS, based on building a new test method. Main research contents: (1)Develop evolution analysis test system of geotechnical three-dimensional micro-structure which is bimodal fusion of optical test and Micro-CT test. (2)By means of experimental study of micro-structure, analyze the change rule of FMLS micro-structure under effects of initial damage, vehicle dynamic load, dry-wet circulation, chemical erosion and other adverse factors, and reveal durability deterioration law and damage mechanism. (3)Using damage theory, etc, study the damage amount which is able to describe durability deterioration process of FMLS under initial damage and various engineering conditions, and build damage evaluation equation which includes change characteristic parameter of micro-structure. Research results are beneficial not only to safe and scientific popularization & application of new geotechnical material, but also to promoting the development of the micro-structure test technology of rock and soil in China.