New experimental methods for engineering properties of overburden of dam foundation and their applications
CHENG Zhan-lin, PAN Jia-jun, ZUO Yong-zhen, HU Sheng-gang, CHENG Yong-hui
Yangze River Scientific Research Institute, Key Laboratory of Geotechnical Mechanics and Engineering of The Ministry of Water Resources, Wuhan 430010, China
Abstract：For many high rockfill dams, which are constructed or will be constructed in Southwest China, deep overburden is one of the most complex engineering problems. The deformation and stress status play an important role in the safety of dams. For the traditional methods, because it’s almost impossible to collect gravel overburden layer samples, the original density cannot be determined exactly. Thus, it is very difficult to get the reliable mechanical and seepage properties of overburden layer in laboratory tests. A new method that indirectly calculates the original density of overburden gravel using pressuremeter tests (PMT) or dynamic penetration tests (DPT) is proposed. In the construction period of Wudongde, this method is successfully applied to the determination of the density of overburden layer. Furthermore, based on the indoor model tests, it is verified that the correction factor of rod length in DPT follows the description of Newton elastic collision theory. Therefore, a new pressuremeter probe with high pressure and side expansion is developed in order to conduct the whole-process pressuremeter tests on deep overburden. The proposed whole set method provides an important technical support for further studies on the engineering properties of deep overburden of dam foundation.
程展林, 潘家军, 左永振, 胡胜刚, 程永辉. 坝基覆盖层工程特性试验新方法研究与应用[J]. 岩土工程学报, 2016, 38(z2): 18-23.
CHENG Zhan-lin, PAN Jia-jun, ZUO Yong-zhen, HU Sheng-gang, CHENG Yong-hui. New experimental methods for engineering properties of overburden of dam foundation and their applications. Chinese J. Geot. Eng., 2016, 38(z2): 18-23.
[1] 党林才, 方光达. 深厚覆盖层上建坝的主要技术问题[J]. 水力发电, 201l(37): 24-29. (DANG Lin-cai, FANG Guang-da. Technical problems of constructing dam on deep overburden[J]. Hydraulic Power Generation, 2011(37): 24-29. (in Chinese)) [2] 汪小刚, 刘小生, 陈 宁, 等. 深厚覆盖层力学特性测试技术研究[M]. 北京: 中国水利水电出版社, 2011. (WANG Xiao-gang, LIU Xiao-shen, CHEN Ning, et al. Researches on testing techniques for mechanical properties of deep overburden[M]. Beijing: China Water & Power Press, 2011. (in Chinese)) [3] PALMER D, NIKROUZ R, SPYROU A. Statics corrections for shallow seismic refraction data[J]. Exploration Geophysics, 2005, 36: 7-17. [4] 《工程地质手册》编委会. 工程地质手册[M]. 4版. 中国建筑工业出版社, 2007. (Engineering Geological Manuals Committee. Engineering geological manual[M]. 4th ed. Beijing: China Architecture and Building Press, 2007. (in Chinese)) [5] 李树武, 张国明, 聂德新. 西南地区河床覆盖层物理力学特性相关性研究[J]. 水资源与水工程学报, 2011, 22(3): 119-123. (LI Shu-wu, ZHANG Guo-ruing, NIE De-xin. Research on correlation of physics—mechanics characters in river bed overburden layer in southwest area[J]. Journal of Water Resources and Water Engineering, 201l, 22(3): 119-123. (in Chinese)) [6] 胡胜刚, 左永振, 饶锡保, 等. 基于模型试验的河床砂砾石层基本特性研究[J]. 长江科学院院报, 2012, 29(11): 55-58. (HU Sheng-gang, ZUO Yong-zhen, RAO Xi-bao, et al. Model test on the physical property of riverbed sand-gravel layer of dam foundation[J]. Journal of Yangtze River Scientific Research Institute, 2012, 29(11): 55-58. (in Chinese)) [7] 石修松, 程展林, 左永振, 等. 坝基深厚覆盖层密度辨识方法[J]. 岩土力学, 2011, 32(7): 2073-2078. (SHI Xiu-song, CHENG Zhan-lin, ZUO Yong-zhen, et a1. Density identification method of dam foundation deep overburden[J]. Rock and Soil Mechanics, 2011, 32(7): 2073-2078. (in Chinese)) [8] 左永振, 程展林, 丁红顺, 等. 动力触探杆长修正系数试验研究[J]. 岩土力学, 2014, 35(5): 1284-1288. (ZUO Yong-zhen, CHENG Zhan-lin, DING Hong-shun, et al. Study of modified coefficient of dynamic penetration rod length[J]. Rock and Soil Mechanics, 2014, 35(5): 1284-1288. (in Chinese)) [9] JTJC20—2011公路工程地质勘察规范[S]. 2011. (JTJC20—201 Specifications for survey of highway engineering geology[S]. 2011. (in Chinese)) [10] GBJ7—89 建筑地基基础设计规范[S]. 1989. (GBJ7—89 Code for design of building foundation[S]. 1989. (in Chinese)) [11] ASTM D4633—86. Standard test method for stress wave energy measurement for dynamic penetrometer testing systems[S]. 1986. [12] 黄熙龄. 旁压试验及粘性土形变模量的测定[C]// 第一届土力学及基础工程学术会议论文选集. 北京, 1964: 4-6. (HUANG Xi-ling. Determination of pressuremeter test and clay soil deformation modulus[C]// Proceedings of the First Symposium on Soil Mechanics and Foundation Engineering. Beijing, 1964: 4-6. (in Chinese))
