The interaction between soil and geosynthetics is an important issue in the research of reinforcement mechanism, and the properties of reinforcement material are key parameters in the design of reinforced-soil structure. A new multifunctional soil-geosynthetics testing machine has been developed on the basis of conventional direct-shear test apparatus. The machine consists of two sets of servo motor, automatic control and data acquisition system, and a set of shear box with dimension of 600mm×300mm×300mm, etc. Direct-shear test, pull-out test, confined-tension test and confined-creep test can be conducted on the machine through several auxiliary means and control modes. Furthermore, the sand-confined tensile strength and creep properties of different geogrids were tested and compared. The contribution of geogrid-soil interaction to the strength of soil-geosynthetics was also analyzed. The tests validated that the machine has good operability and accuracy.
Key words
soil-geosynthetics testing machine /
servo control /
interaction of soil-geosynthetics /
pull-out test /
confined tension test /
confined creep test
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
References
[1] 李广信. 关于土工合成材料加筋设计的若干问题. 岩土工程学报, 2013, 35(4): 605-610.
丁金华, 包承纲, 陈仁朋. 加筋土结构中筋材抗拉强度的取值方法研究. 水利学报, 2012, 43(12): 1464-1469.
包承纲, 汪明远, 丁金华. 格栅加筋土工作机理的试验研究. 长江科学院院报, 2013,30(1):34-41.
SL235—2012, 土工合成材料测试规程. 北京:中国水利水电出版社, 2012.
GB/T 17689—2008, 土工合成材料-塑料土工格栅. 北京:中国标准出版社, 2008.
DOBIE M, 何 波. 加筋土结构设计方法及设计安全冗余分析. 长江科学院院报, 2014, 31(3): 115-121.
FHWA-NHI-10-024/025, AASHTO LRFD Bridge Construction Specifications. Design and Construction of Mechanically Stabilized Earth Walls and Reinforced Soil Slopes. U.S.: Federal Highway Administration, U.S. Department of Transportation, 2010.
NAKAMURA T, MITACHI T. In-soil Creep Deformation Behavior of Geogrid and Its Estimation Method.Proceedings of the Japan Society of Civil Engineers, 2002,(722):265-273.
JEON H Y, GONG H B, KANG S G. Analytical Approach to Long-term Creep Behaviors of Geosynthetic Reinforcements∥Proceedings of the 9th International Conference on Geosynthetics, Brazil. November 18, 2010:777-780.
ASTM D6992—2009,Standard Test Method for Accelerated Tensile Creep and Creep-Rupture of Geosynthetic Materials Based on Time-Temperature Superposition Using the Stepped Isothermal Method.West Conshohocken,PA: ASTM International,2009.
QB/T 2854—2007, 塑料土工格栅蠕变试验和评价方法. 北京:中国轻工业出版社, 2007.
李丽华, 王 钊. 加速土工合成材料蠕变试验的时温叠加法简介. 长江科学院院报, 2004, 21(1):29-32.
TONG J, GONG B, LIU J. Experimental Study and Prediction on the Long-term Creep Properties for Geogrids at Different Temperatures∥Proceedings of the 9th International Conference on Geosynthetics, Brazil. November 18, 2010: 873-876.