
2012年9月上第41卷第372期
施工技术
CONSTRUCTION TECHNOLOGY
高速公路路基加筋红层泥岩填料三轴试验研究
姜兵,卢萍,韩志型
(西南科技大学土木工程与建筑学院,四川绵阳621010)
【摘要】采用三轴试验主要从施工压实度方面对红层泥岩填料的物理力学特性进行研究。试验表明,压实度的提高虽然可以提高素土体的强度,但同时也降低其延性,加入土工化合物后可增加土颗粒的侧向约束、提高其围压达到改善土体路用性能的目的,同时加筋后不仅大幅提高了红层泥岩填料的峰值强度与残余强度,而且增大了峰值应变的区间并改变了土体的应力-应变模式。结合现行施工规范分别给出红层泥岩素填料及加筋填料合理的施工压实度,为确定高速公路施工压实度提供了可靠的数据支持。
【关键词】公路工程;路基;红层泥岩;土工合成材料;试验;三轴试验;压实度
[中图分类号】TU449
[文献标识码]A
【文章编号】1002-8498(2012)17-0047-03
Triaxial TestStudy on ReinforcedRed-bed MudstoneforHighwayEmbankment
Jiang Bing,Lu Ping,Han Zhixing
(School of Civil Engineering and Architecture, Southwest Unisersity of Science and Technology,
Mianyang,Sichuan621010,China)
Abstract: Physical properties of red-bed mudstone were studied using triaxial test with the degree of compaction as the main investigated parameter. Test result shows that by inereased the degree of compaction, the plain soil strength can be increased as well, but ductility will be decreased. By adding geo-symthetic materials, the confining pressure of the grains can be increased and as a result, pavement performances can be improved. The peak strength and residual strength of the red-bed rock can be increased significantly by the reinforcement. .The reinforcement also changes the stress-strain mode and increased the duration of the peak strain. With reference to the current codes, the reasonable degree of compaction of the plain soil and the reinforcing fller are suggested. The work presented provided reliable support to the determination of the degree of compaction in highway construction.
Key words:road construction; embankment; red-bed mudstone; geosynthetic material; testing; triaxial test; compaction degree
西南地区是国内红层泥岩规模最大、类型最特殊的地区之一,同时西南地区地形地貌复杂,高速公路修筑中不可避免地会遇到大量的高填方路基,目前对于此路段多采用换填优质填料,但是对于难以获取换填材料路段此举弊端显而易见(1]。随着基础建设工程的逐步发展,在土中加人土工合成材料在解决路基不均匀沉降问题方面显示出突出的优势。六武高速[2]、怀新高速[3]、安楚高速(4]等多
【收稿日期】2011-12-29:[修订日期】2012-03-05
[基金项目]国家自然科学基金项目(10602048);四川省自然科学基金资助项目(2009YJ0060)
【作者简介】姜兵,讲师,E-mail:jiangbing0828@126.com 万方数据
47
条高等级公路都采用加筋砂砾填料的方式处治高填方路基沉降病害,最高处治高度达到32.8m。调查发现(34),西南地区高填方路基施工过程中往往存在压实度不足或不均匀的间题,面大量的事实表明,提高压实度是解决路基沉降病害的重要措施。然而目前我国的高速公路路基对于中低路堤、高路堤均采用相同的标准,同时现行的《公路路基施工技术规范》JTGF10—2006[9】(以下简称“规范")对于加筋复合土仍采用素土压实标准,同样也缺乏充分的科学依据,因此很有必要研究土体压实度对红层泥岩路基填料的强度和变形特性的影响。本文的研究对于拓展西南地区高填方路段填料问题具有重要的基础理论及实践意义。