Lateral influence rules on explosion-compacted loess embankment by linear explosive bars
-
摘要: 为了合理设计既有公路路堤爆炸挤密钻孔的平面布置方案,以爆炸挤密加固某高速公路黄土路堤为例,研究了条形药包爆炸挤密黄土路堤的横向影响规律。先根据该高速公路实际几何尺寸和材料参数建立有限元模型,然后用ANSYS/LS-DYNA分等横截面不等长和等长不等横截面两类条形药包共计16种工况进行数值模拟,得出爆腔水平半径、土壤密度峰值及其位置和爆炸挤密黄土路堤横向影响半径的变化规律,此外还拟合出横截面为2支药管组成的条形药包爆炸挤密后土壤的密度增量与该点距爆心的水平距离和药量之间的关系表达式。最后,结合工程实例,说明了上述规律在施工方案设计中的应用。Abstract: In order to rationally design the plane layout scheme of drilling holes for explosion compacting the loess embankment of an existing highway, this paper took the loess embankment of a highway reinforced by explosion compaction(EC) as an example and studied the lateral influence rules on EC with linear explosive bar. Firstly, a finite element model was established according to the actual geometry and material parameters of the highway. Then, based on the numerical simulation of sixteen cases carried out by ANSYS/LS-DYNA, the change rules of the horizontal radius of the explosion cavity, the peak values of soil density and their position, the lateral influence radius of explosion compacting loess embankment were obtained. These sixteen cases belong to two kinds of situations. One kind is of explosive bars with equal cross section and unequal length, while another one is of those with equal length and unequal cross section. Moreover, the relationship functions among the increment of soil density after EC with the explosive bar whose cross section was composed of two explosive tubes, the horizontal distance to the core of the explosive bar and the amount of explosive were fitted. Finally, combined with the actual EC engineering of the highway, the application of the above rules in the design of construction scheme was illustrated.
-
Key words:
- road engineering /
- explosion compaction /
- linear explosive bar /
- loess embankment /
- lateral influence
-
表 1 有限元模型中路面结构层的主要参数
Table 1. Key parameters of pavement structure layers in finite element model
结构层 ρc/(g·cm-3) Ec/MPa μc σcy/MPa Ecτ/MPa βc 路面层 2.70 350 0.20 0.8 30 0.40 基层 2.40 460 0.27 0.5 42 0.80 垫层 2.20 390 0.28 0.3 35 0.60 -
[1] 吴银柱.土力学与基础工程[M].北京:高等教育出版社, 2012:270. [2] 梁桥欣, 郑明辉, 张维, 等.软弱地层路基加固效果方案优化研究[J].国防交通工程与技术, 2015(6):37-40. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=gfjtgcyjs201506010LIANG Qiaoxin, ZHENG Minghui, ZHANG Wei, et al. A study of the optimization of the consolidating schemes for roadbeds in the soft stratum[J]. Traffic Engineering and Technology for National Defence, 2015(6):37-40. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=gfjtgcyjs201506010 [3] 张铁军.干拌水泥碎石桩路基加固技术[J].交通标准化, 2014, 42(10):62-67. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=jtbzh201410021ZHANG Tiejun. Subgrade reinforcement technology of dry mixed cement gravel pile[J]. Transportation Standardization, 2014, 42(10):62-67. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=jtbzh201410021 [4] 张小斌.公路路基工程防护与加固浅析[J].长沙铁道学院学报(社会科学版), 2014, 15(2):311-312. http://d.wanfangdata.com.cn/Periodical_cstdxyxb-shkxb201402150.aspxZHANG Xiaobin. Analysis of protection and reinforcement of highway subgrade engineering[J]. Journal of Changsha Railway University (Edition of Social Sciences), 2014, 15(2):311-312. http://d.wanfangdata.com.cn/Periodical_cstdxyxb-shkxb201402150.aspx [5] CHU J, VARAKSIN S, KLOTZ U, et al. Construction processes[C]//Proceedings of the 17th International Conference on Soil Mechanics and Geotechnical Engineering. Alexandria, 2009: 3008-3011. [6] 陈涛, 郭院成, 顾强康.爆炸法加固黄土地基数值模拟[J].重庆建筑大学学报, 2007, 29(6):80-83. http://d.wanfangdata.com.cn/Periodical_cqjzdxxb200706018.aspxCHEN Tao, GUO Yuancheng, GU Qiangkang. Numerical simulation of explosion method in loess ground treatment[J]. Journal of Chongqing Jianzhu University, 2007, 29(6):80-83. http://d.wanfangdata.com.cn/Periodical_cqjzdxxb200706018.aspx [7] 中华人民共和国建设部. 建筑桩基技术规范: JTJ 94-2008[S]. 北京: 中国建筑工业出版社, 2008: 7-9. [8] 中华人民共和国住房和城乡建设部. 建筑地基基础设计规范: GB50007-2011[S]. 北京: 中国建筑工业出版社, 2011: 120-123. [9] SOLYMAR Z V, ILOABACHIE B C, GUPTA R C, et al. Earth foundation treatment at Jebba Dam Site[J]. Journal of Geotechnical Engineering, 1984, 110(10):1415-1430. doi: 10.1061/(ASCE)0733-9410(1984)110:10(1415) [10] LA FOSSE U, GELORMINO T A. Soil improvement by deep blasting: A case study[C]//Proceedings of 17th Annual Symposium on Explosives and Blasting Technique. Lasvegas: International Society of Explosive Engineers, 1991, Vol. 1: 205-213. [11] MURRAY P, SINGH N K, HUBER F, et al. Explosive compaction for the Seymour Falls Dam seismic upgrade[C]//Proceedings on the 59th Canadian Geotechnical Conference, 2006: 218-237. [12] NARSILIO G A. Spatial variability and terminal density: Impication in soil behavior[D]. Atlanta: Georgia Institute of Technology, 2006: 247. [13] FORDHAM C J, MCROBERTS E C, PURCELL B, et al. Practical and theoretical problems associated with blast densification of loose sands[C]//Proceedings of the 44th Canadian Geotechnical Conference of the Canadian Geotechnical Society. Richmond, Canada: Canadian Geotechnical Society, 1991: 92-98. https://www.researchgate.net/publication/296007609_Practical_and_theoretical_problems_associated_with_blast_densification_of_loose_sands [14] GANDHI S R, DEY A K, SELVAM S. Densification of pond ash by blasting[J]. Journal of Geotechnical and Geoenvironmental Engineering, 1999, 125(10):889-899. doi: 10.1061/(ASCE)1090-0241(1999)125:10(889) [15] GOHL W B, JEFFERIES M G, HOWIE J A, et al. Explosive compaction: Design, implementation and effectiveness[J]. Géotechnique, 2000, 50(6):657-665. doi: 10.1680/geot.2000.50.6.657 [16] HALL C E. Compacting a dam foundation by blasting[J]. Journal of the Soil Mechanics and Foundations Division, 1962, 88(3):33-51. http://cedb.asce.org/CEDBsearch/record.jsp?dockey=0257666 [17] NARSILIO G A, SANTAMARINA J C, HEBELER T, et al. Blast densification: Multi-instrumented case history[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2009, 135(6):723-734. doi: 10.1061/(ASCE)GT.1943-5606.0000023 [18] RAJU V R, GUDEHUS G. Compaction of loose sand deposits using blasting[C]//Proceedings of the 13th International Conference on Soil Mechanics and Foundation Engineering, 1994: 1145-1150. [19] ROLLINS K M, ANDERSON J K S. Cone penetration resistance variation with time after blast liquefaction testing[C]//Proceedings of Geotechnical Earthquake Engineering and Soil Dynamics Ⅳ. Reston, VA, USA: Geotechnical Special Publication, 2008: 181. http://www.researchgate.net/publication/269157328_Cone_Penetration_Resistance_Variation_with_Time_after_Blast_Liquefaction_Testing [20] SOLYMAR Z V. Compaction of alluvial sands by deep blasting[J]. Canadian Geotechnical Journal, 2011, 21(2):305-321. doi: 10.1139/t84-032?journalCode=cgj [21] WILD P A. Tower foundations compacted with explosives[J]. Electrical World, 1961(66):36-38. http://cedb.asce.org/CEDBsearch/record.jsp?dockey=0288788 [22] 董亮, 叶阳升, 蔡德钩, 等.爆炸荷载作用下软土地基的变形特性[J].爆炸与冲击, 2007, 27(5):416-467. doi: 10.11883/1001-1455(2007)05-0416-04DONG Liang, YE Yangsheng, CAI Degou, et al. Deformation behavior of soft soil ground under explosive loading[J]. Explosion and Shock Waves, 2007, 27(5):416-467. doi: 10.11883/1001-1455(2007)05-0416-04 [23] ESLAMI A, PIROUZI A, OMER J R, et al. CPT-based evaluation of blast densification (BD) performance in loose deposits with settlement and resistance considerations[J]. Geotechnical and Geological Engineering, 2015, 33(5):1279-1293. doi: 10.1007/s10706-015-9900-x [24] FINNO R J, GALLANT A P, SABATINI P J. Evaluating ground improvement after blast densification: Performance at the Oakridge landfill[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2016, 142(1):1-13. doi: 10.1061/%28ASCE%29GT.1943-5606.0001365 [25] 国家能源局. 水电水利工程爆破施工技术规范: DL/T 5135-2013[S]. 北京: 中国电力出版社, 2014: 10-12. [26] 魏连雨, 刘艳竹, 马士宾, 等.高填方路堤软弱区域爆炸挤密技术[J].科技导报, 2014, 32(15):49-52. doi: 10.3981/j.issn.1000-7857.2014.15.006WEI Lianyu, LIU Yanzhu, MA Shibin, et al. EC technology of the weak area of the high-filled embankment[J]. Science & Technology Review, 2014, 32(15):49-52. doi: 10.3981/j.issn.1000-7857.2014.15.006 [27] 魏连雨, 刘艳竹, 李海超, 等.高填方路堤土中爆破数值模拟[J].科技导报, 2014, 32(32):32-36. doi: 10.3981/j.issn.1000-7857.2014.32.005WEI Lianyu, LIU Yanzhu, LI Haichao, et al. Numerical simulation of blasting in highly filled embankment soil[J]. Science & Technology Review, 2014, 32(32):32-36. doi: 10.3981/j.issn.1000-7857.2014.32.005 [28] Livermore Software Technology Corporation. LS-DYNA keyword user's manual[M]. Livermore: Livermore Software Technology Corporation, 2013:Vol.Ⅱ.2.64-2.66. [29] 杨秀敏.爆炸冲击现象数值模拟[M].合肥:中国科学技术大学出版社, 2010:335-338. [30] 林大能, 胡伟, 彭刚.岩土介质爆炸挤压特性分析[J].岩石力学与工程学报, 2003, 22(11):1767-1770. doi: 10.3321/j.issn:1000-6915.2003.11.002LIN Da'neng, HU Wei, PENG Gang. Analysis on blasting extrusion characteristic of soil and rock[J]. Chinese Journal of Rock Mechanics and Engineering, 2003, 22(11):1767-1770. doi: 10.3321/j.issn:1000-6915.2003.11.002