摘要
通过溶滤试验研究额哈(额济纳—哈密)铁路沿线石膏土的溶陷变形特性,得到了分别采集自平地和山地的2种石膏土在不同荷载作用下的溶陷变形系数和变形稳定时间,并探讨了石膏土产生溶陷变形的原因及荷载、含盐量、颗粒级配对石膏土溶陷变形的影响。试验结果表明:石膏土中的可溶盐是石膏土产生溶陷变形的根本原因。当外荷载不变时,石膏土浸水后短时间内可产生较大变形,占到稳定变形的80%以上,其后在长期溶滤作用下仍可产生较大变形。石膏土的溶陷变形随荷载的增大而增大。随着溶滤时间的延长,可溶盐含量逐渐减少,石膏土的溶陷变形随荷载增大趋于稳定。溶陷变形的大小与石膏土的含盐量有关。在相同外荷载作用下,含盐量越高石膏土溶陷变形越大。溶陷变形的速度主要与土的颗粒级配有关。石膏土中粗颗粒含量越大其溶陷变形速度越快。
Collapse deformation characteristics of gypsum soil along Ejina-Hami railway were studied by lixiviation test. The collapse deformation coefficient and deformation stability time of two kinds of gypsum soils collected respectively from plain and mountainous areas under different loads were obtained. Reasons that cause the collapse deformation of gypsum soil were probed, and influences of load, salt content and grain composition on the collapse deformation of gypsum soil were discussed. The results show that the soluble salt in gypsum soil is the root cause of the deformation of gypsum soil. Gypsum soil deforms largely within a short time after soaking under a constant load, accounting for more than 80% of the stable deformation, and then large deformation can still occur under the action of long-term lixiviation. The collapse deformation of the gypsum soil increases with the increase of the load. With the prolongation of lixiviation time, the soluble salt content decreases gradually, and the deformation of gypsum soil stabilizes with the increase of load. The amount of the Collapse deformation is related to the salt content of gypsum soil. Collapse deformation increases with the increase of salt content under the same load. The velocity of Collapse deformation is mainly related to the grain composition. The more coarse particles the gypsum soil has, the faster the collapse deformation will be.
出处
《铁道建筑》
北大核心
2017年第5期104-108,共5页
Railway Engineering
关键词
铁路路基
溶陷变形
试验研究
石膏土
额哈铁路
溶滤试验
Railway subgrade
Collapse deformation
Experimental study
Gypsum soil
Ejina-Hami railway
Lixiviation test
