基于分形机制的红砂岩路基填筑现场试验研究  

Field Test Research for Subgrade Filling of Red Sandstone based on Fractal Mechanism

作　　者：傅强 刘晓明[2] 

机构地区：[1]湖南省通平高速公路建设开发有限公司,湖南平江414500 [2]湖南大学土木工程学院,湖南长沙410082

出　　处：《公路工程》2011年第5期1-6,17,共7页Highway Engineering

基　　金：国家自然科学基金项目(50808076);湖南省科技推广重点项目(2007CK3065)

摘　　要：红砂岩的软化和崩解是具有复杂机制的物理现象。本文结合湖南通城至平江高速公路工程中遇到红砂岩,基于红砂岩崩解过程的分形机理,针对红砂岩崩解过程中的颗粒及其分数维变化特征,建立红砂岩完全崩解的分维数指标,并开展现场试验。试验结果表明:通平高速公路红砂岩属于III类红砂岩,但仍会崩解,故不能作为填石路堤对待;红砂岩崩解颗粒及其分数维变化的临界值最后稳定在2.6～2.7之间;采用"光静1遍+羊静1遍+羊振4～5遍+光振1遍+光振1遍"处治的红砂岩下路堤最大粒径控制在25 cm以下的能力,弯沉满足设计要求;路基中的红层填料的分数维基本满足2.6～2.7要求,采用该工艺处治后的红砂岩路基崩解已经趋于完成,可用于93区填筑。It is a physical phenomenon with complex mechanism for softening and disintegration of red sandstone. In this paper, combined with the red sandstone geological conditions encountered in the Tongcheng-Pingjiang Expressway Project in Hunan Province, based on fractal mechanism of red sandstone disintegration process,the index of fractal dimension is established for red sandstone disintegration com- pletely, aimed on the particles and their fractal dimension change characteristics in the process of red sandstone disintegration. And the field test is carried out. Test results show that the red sandstone class III of Tong-Ping expressway is categorized to the red sandstone class III, but it will still disintegrate and can not be treated as rockfill embankment filler. The critical value of disintegration particle of and red sand- stone and its fractal dimension changes stabilizes at 2.6 to 2.7 finally. And the treatment of ＂static rolling by smooth-wheeled roller one times ＋ static rolling by tamping foot vibratory roller one times ＋ vibration rolling by tamping foot vibratory roller 4 - 5 times ＋ vibration rolling by smooth-wheeled roller one times ＋ vibration roiling by smooth-wheeled roller one times＂, make the maximum size of red sandstone con- trolled below 25 cm and have deflection less than the design requirements. The fractal dimension of redbed filler in subgrade basically meets the requirements of 2.6 to 2.7, and the disintegration of red sandstone subgrade has come to complete, then can used as 93 section filling material.

关 键 词：路基工程 红砂岩 分形机理 分数维 现场试验 

分 类 号：U416.03[交通运输工程—道路与铁道工程]