摘要
本文结合郑民高速公路项目,针对高速公路粉砂土路基的技术特点,首先分析了粉砂土的动力特征,然后对本文计算方法进行了介绍,接着系统分析了粉砂土路基在地震荷载、汽车、飞机作用下的动力响应,得到以下结论:在汽车荷载作用下,边坡内孔隙压力、位移以及应力随着加载频率的增加,车轮下一定范围内的孔压累积加快,有效应力相应减小,边坡位移增大,且坡面上的点更多地向坡内位移;飞机荷载作用下孔隙水压和位移随加载频率和加载次数的增大而增大,且边坡顶部产生向坡内的水平位移;另外,边坡内的瞬时屈服区或破坏区随加载频率的增大而扩大;随着地震加速度峰值的增加,路堤内拉力区和屈服区的范围增大,液化出现的可能性也增大。特别地指出,当地震加速度达到0.1g时,并不能完全排除路基土液化的可能性。最后通过室内模型试验验证了数值计算分析结果的合理性,揭示了高速公路粉砂土路基的动力响应特性。
在我国,水力成因的粉砂土广泛分布于冲积平原、河流三角洲、沿海平原地区,因此粉砂土路基的高速公路在我国必将得到广泛应用。本文研究结论将对河南及国内高速公路粉砂土路基的设计及施工控制提供有益的参考和工程实践指导,对确保高速公路的修筑质量、延长使用寿命具有重要意义,应用前景广泛。
Combining Zhengmin Highway Project, this paper firstly analyzed the dynamic characteristics of the silty soil in view of the technique characteristics of highway with silty soil roadbed, then introduced the adopted calculation methods in the paper, and systematically analyzed the dynamic response of the silty soil roadbed under the actions of the earthquake loading, autos and airplanes. It came to conclusions as follows:under the actions of autos loading, the pore pressure, displacement and stress of the slope increased with the enhanced loading frequency. Within the limits underneath the wheels, the pore pressure speeded up the accumulation, the effective stress reduced relatively, and the slope displacement augmented, the points on the slope displaced more towards the inner slope; under the actions of the airplane loading, the pore water pressure and displacement augmented with the increasing loading frequency and times, and the top of the slope caused the horizontal displacement towards the inner slope; in addition, the transient yield or the destruction region of the slope enlarged with the increasing loading frequency; with the increasing earthquake acceleration peak, the tension and yield region range of the road embankment augmented, and the possibility of the liquidity was increased as well. It specially pointed out that the liquefaction possibility of the roadbed soil couldn't be excluded completely when the earthquake acceleration reached0.1g. Finally, it validated the analysis result rationality of the value calculation by the indoor model experiment, and disclosed the dynamic response characteristics of the highway with silty soil roadbed.
In our country, silty soil caused by the hydraulic power is widely distributed in alluvial plain, river delta and coastal plain zone,Therefore, silty soil roadbed must be widely applied in our country. The research conclusion in this paper will provide some beneficial reference for the design of the silty soil roadbed in Henan and other domestic highway, as well as its construction control and put forward the practical instruction in the projects. It possesses the vital significance to assure the building quality of the road and extend the service life. The application prospect is wide.
引文
[1]孙淑勤,李雯,中、日公路土质路堤压实控制方法比较[J],国外公路,2001(21):2.
[2]Anon.Dynamic compaction used to solve Montana Soils problem[J]. BetterRoads, 1986,56(7);40-52,
[3]Anon.Dam foundations strengthened by deep dynamic compaction[J].Highway and construction,1987:70-71.
[4]Wallays,M.Deep compaction by certical and horizontal vibration.Recent Developments in Ground Improvement Techniques,1985 A.A Balkema P53-70.
[5]申爱琴,郑南翔,苏毅等.含砂低液限粉土填筑路基压实机理及施工技术研究[J].中国公路学报,2000,13(4).
[6]杨占宝.黄河三角洲地震地质特征研究[D].[硕士学位论文].山东青岛:中国海洋大学,2003
[7]林霖.现代黄河水下三角洲粉土动力特性及液化破坏研究[D].[硕士学位论文]山东青岛:中国海洋大学,2003.
[8]董淑云.黄河三角洲地基土地震液化的试验研究和数值模拟[D].[硕士学位论文]山东青岛:中国海洋大学,2004
[9]马德翠.黄河口粉质土体的动力响应特性及机理研究[D].[硕士学位论文].山东青岛:中国海洋大学,2005.
[10]贾永刚,霍素霞,许国辉.黄河水下三角洲沉积物强度变化原位测试研究[J].岩土力学,2004,25(6)
[11]迟世春,郭晓霞,杨峻.土的动力Hardin-Drnevich模型小应变特性及其阈值应变研究[J].岩土工程学报,2008,30(2):243-249.
[12]ISHIHARAK, TATSUOKA F, YASUDA S. Sand liquefaction in hollow cylinder cylinder torsion under irregular excitation [J]. Soils Foundations,1975,15(1):45-49.
[13]Finn W D L,Bhatia S K.Verification of nonlinear effective stress model in simple shear proceedings.ASCE Fall Meeting,1980.
[14]谢定义,张健民.往返荷载下饱和砂土强度变形瞬态变化的机理,土木工程学报,1987(8):387-397;
[15]谢定义,张健民.周期荷载下饱和砂土强度变形瞬态孔隙水压力的变化机理与计算模型,土木工程学报,1990(5):564-572;
[16]谢定义,张健民.饱和砂土瞬态动力学特性与机理分析,西安,陕西科学技术出版社,1995.
[17]HABIBALLAHT, CHAZALLONC. An Elastoplastic Model Based on the Shakedown Concept for Flexible PavementsUnbound Granular Materials [J]. International Journal of Numeric and Analysis Method in Geomechnics,2005 (29):577-596.
[18]SEED H B, CHAN C K, MONISMITHC L. Effect of Repeated Load on the Strength and Deformation of Compacted Clay [J]. Highway Research Record,1955 (34):541-558.
[19]BROWN S F, HYDE A F L. Significance of Cyclic Confining Stress in Repeated Load Triaxial Testing of Granular Materials[J]. Transportation Research Record,1985 (537):49-58.
[20]BARKSDALE R D. Laboratory Evaluation of Rutting in Base Course Materials [C]// Proceedings of the 3rd International Conference on Structural Design of Asphalt Pavements, London:Park Lane,1972:161-174.
[21]SWEERE G T H. Unbound Granular Bases for Roads [D]. Delft:University of Delft,1990.
[22]PAPPIN J W. Characteristics of a Granular Material for Pavement Analysis [D]. Nottingham:University of Nottingham,1979.
[23]沙庆林.路基压实与压实度标准[M].北京:人民交通出版社,1997.
[24]张立辉,郑华,尹丽艳.粉砂土路基施工技术[J].交通科技与经济,2002,(3).
[25]吴泊人.浅议粉土的工程特性[J].安徽建筑,2002,(1).
[26]徐根洪,丁晓光.某高速公路路底基层粉土稳定土试验[J].安徽建筑,2006,(3).
[27]石桂梅,李天鸿.粉质砂土填土路堤压实标准的研究[J].科技咨询导报,2007,(23).
[28]孙明漳,左佐生,刘国栏等.路基填土压实及检测方法.北京:中国铁道出版社,1999.
[29]郭庆国.粗粒土的工程特性及应用.郑州:黄河水利出版社,1999
[30]河南省交通厅科学技术研究院.洛三高速公路高填土冲击压实机具施工工艺研究报告[R],2000.
[31]吕文江,赵进.冲击式压路机对路基进行补充碾压的效果分析[J].公路,2002(8).
[32]贾海华.冲击压实技术在高速公路路基施工中的应用[J].土工基础,2000(3).
[33]N. Mocavitt,M.R. Yats, M.C. Forde:Dynamic Stiffness Analysis of Concrete Pavement[J]. Journal of Transportation Engineering, ASCE, No.4:1992
[34]U.S. Department of Transportation, Federal Aviation Administration. Airport Pavement Design and Evaluation, AC No:150/5320-6D. U.S. Department of Transportation, Federal Aviation Administration,1995.7.
[35]Duncan,J.M., L.Monismith and E.L.Wilson. Finite Element Analysis of Pavement[C] TRB, National Research Council, Washington, D.C.
[36]Navneet Carg, Erol Tutumluer & Marshall R.Thompson. Structural Modelling Concepts for the Design of Airport Pavements for Heavy Aircraft[c]. Fifth International Conference on the Bearing Capacity of Roads and Airfields, Trondheim, Norway, July,1998.
[37]Goniez-Ramirez, F.M. and Thompson, M.R. Characterizing Aircraft Multiple Wheel Load Interaction for Airport Flexible Pavement Design. Civil Eng Studies, [R], Univ of Illinois at Urbana-Champaign,2002.
[38]赵鸿铎.适应大型飞机的沥青道面交通荷载分析方法及参数的研究[D].上海:同济大学.
[39]杨群,黄晓明.沥青稳定基层与半刚性基层疲劳设计分析[J].公路交通科技,2001,(6).
[40]Sherif Yehia. Conductive Concrete Overlay for Bridge Deck Deicing:Mixture Proportioning. Optimization and properties[J]. ACI Materials Journal.2000,97(2):172-181.
[41]Katarzyna Zwarycz. Snow Melting and Heating Systems Based on Geothermal Heat Pumps at Golemiow Airport Poland[R]. Goethermal Training Programme Reports, The United Nations University, Iceland,2002.
[42]NCHRP Report 350.Recommened Proeedures for the Safety Performance Evaluation of Highway Features[R].1993
[43]Paul Miller and JohnF. Computer Simulations of Roadside Crash Cushion Impacts[J].Journal of Transportation Engineering,1997.
[44]张洪亮.路桥过渡段车路动力学分析及容许差异沉降研究[D].西安:长安大学,2003.
[45]Ritter. W. Stcin, F. Janssen. Traffic Sign Recognition Using Colour Information [J]. Mathematical and Computer Modelling,1995.
[46]]Hashim Al-Madani, Abdul-Rahman Al-Janahi. Assessment of Drivers'Comprehension of Traffic Signs Based on Their Traffic, Personal and Social Characteristics[J].Transportation Research,2002,(5):361-374.
[47]凌建明,郑悦锋,金维明.机场道面评价体系研究[J].交通运输工程学报,2001(3):29-33.
[48]呙润华,凌建明.飞机荷载作用下场道地基附加应力特征[J].同济大学学报,2001,29(3):288-293
[49]张友峰,袁海平,FLAC3D在地震边坡稳定性分析中的应用[J]。江西理工大学学报,2008(5),29.