城轨高架桥桩基影响下采空区沉降预测与综合治理研究

Settlement prediction and integrated control technology of pile foundations for urban metro viaducts over underlying goafs

摘要

城市轨道交通高架桥穿越采空区施工时, 覆岩受扰动易引发桩基不均匀沉降甚至结构失稳。为揭示桩基荷载与采空区覆岩变形的互馈影响规律并提出治理技术, 以济南地铁8号线穿越采空区高架桥工程为背景, 结合“砌体梁”理论与Geddes应力公式, 构建了引入附加下沉系数的地表移动修正模型。通过桩长、桩径、桩距三因素正交试验, 分析了设计参数对覆岩沉降特征的影响规律, 并结合数值模拟优选了治理方案。研究结果表明: 覆岩结构在设计荷载下保持稳定, 地表沉降呈“中部大、外围小”的分布特征, 最大沉降约138 mm。数值模拟揭示桩长与桩距是影响覆岩沉降的主控因素, 合理增加桩长可显著改善沉降均匀性。半穿越法治理方案可将相邻桩基沉降差稳定控制在1 mm以内, 较灌注充填法和全穿越法分别降低约2 mm, 同时兼顾经济性与施工效率。该研究结果可为采空区条件下高架桥桩基的优化设计与稳定控制提供理论依据与工程参考。

Abstract

During the construction of urban rail transit viaducts crossing goafs, disturbances to the overlying rock are prone to induce uneven settlement of pile foundations and even structural instability. To reveal the mutual feedback mechanism between pile foundation loads and goaf overlying rock deformation, and propose corresponding control technologies, this study took the viaduct project of Jinan Metro Line 8 crossing goafs as the engineering background. By integrating the “voussoir beam” theory and Geddes stress formula, a modified surface movement model incorporating an additional subsidence coefficient was established. Through orthogonal tests on pile length, pile diameter, and pile spacing, the influence law of design parameters on the settlement characteristics of overlying rock was analyzed, and the optimal control scheme was screened out in combination with numerical simulation. The research results show that the overlying rock structure remains stable under the design load and the surface settlement presents a distribution characteristic of “larger in the middle and smaller in the periphery”, with a maximum settlement of approximately 138 mm. Numerical simulation reveals that pile length and pile spacing are the dominant factors affecting overlying rock settlement, and reasonable increase in pile length can significantly improve settlement uniformity. The half-crossing control scheme can limit the differential settlement of adjacent pile foundations within 1 mm, which is approximately 2 mm lower than that of the grouting filling method and the full-crossing method, while balancing the economy and construction efficiency. The research results can provide a theoretical basis and engineering reference for the optimal design and stability control of viaduct pile foundations under goaf conditions.

关键词

采空区 / 桩基沉降 / 覆岩稳定性 / 桩基参数优化 / 治理方案

Key words

goaf / pile foundation settlement / overlying strata stability / pile parameter optimization / control scheme

参考文献

[1] 王滢, 姚真, 宋永山, 等 . 地铁移动荷载作用下准饱和地基振动特性及隔振研究[J]. 山东科技大学学报 (自然科学版), 2023, 42(5): 48-57.

[2] WANG Ying , YAO Zhen , SONG Yongshan , et al. Study on vibration characteristics and vibration isolation of nearly saturated ground under moving load of subway[J]. Journal of Shandong University of Science and Technology (Natural Science), 2023, 42(5): 48-57.

[3] TRENTINI W V E , PARSEKIAN A G , BITTENCOURT N T . Multiobjective optimization of bridge and viaduct design: Comparative study of metaheuristics and parameter calibration[J/OL]. Engineering Structures, 2024, 312.DOI: 10.1016/J.ENGSTRUCT.2024.118252.

[4] YI X Y, ZHU W B, NING S, et al. Critical height of unfilled zone in underlying gob piles[J/OL]. Shock and Vibration, 2021.DOI: 10.1155/2021/6634295.

[5] 张明光 . 极近距离煤层采空区下巷道支护技术研究[J]. 山东科技大学学报 (自然科学版), 2018, 37(4): 35-41.

[6] ZHANG Mingguang . Roadway support technology in goaf of ultra—close distance coal seams[J]. Journal of Shandong University of Science and Technology (Natural Science), 2018, 37(4): 35-41.

[7] 王金淑, 陈永泽, 梅雪峰, 等 . 膨胀岩土地基中影响桩基抬升的参数分析计算与理论研究[J]. 地质与勘探, 2025, 61(5): 1094-1102.

[8] WANG Jinshu , CHEN Yongze , MEI Xuefeng , et al. Calculation and theoretical research on parameters affecting pile foundation uplift in expansive rock and soil foundations[J]. Geology and Exploration, 2025, 61(5): 1094-1102.

[9] 张乾青 . 竖向抗压桩承载机理与受力特性分析方法[J]. 山东科技大学学报 (自然科学版), 2020, 39(4): 93-105.

[10] ZHANG Qianqing . Bearing mechanism and response analysis method of vertically loaded piles[J]. Journal of Shandong University of Science and Technology (Natural Science), 2020, 39(4): 93-105.

[11] 牛地, 吴倩, 朱成林 . 基于 SBAS—InSAR 技术的安徽省砀山县地面沉降监测[J]. 中国地质调查, 2022, 9(5): 15-23.

[12] NIU Di , WU Qian , ZHU Chenglin . Analysis of monitoring ground subsidence in Dangshan county of Anhui Province based on SBAS—InSAR technology[J]. Geological Survey of China, 2022, 9(5): 15-23.

[13] HAO Q , ZHENG Q Y , LIU S W , et al. Study on the influence of grouting treatment on the movement and deformation of surface in longwall coal mining goaf areas[J]. Mining, Metallurgy and Exploration, 2024, 41(4): 1835-1858.

[14] LU W , GUO Z , HU H , et al. Stability evaluation of mined—out area and borehole grouting treatment: A case study in China[J/OL]. Case Studies in Construction Materials, 2023, 19.DOI: 10.1016/J.CSCM.2023.E02596.

[15] ZHANG Z P, LI F L, CHENG Y, et al. Analysis and research of the stability about the gob of coal mine under the proposed buildings[J]. Advanced Materials Research, 2014(1065/1069): 105-108.

[16] 程强 . 煤矿采空区全充填压力注浆治理及效果评价研究[J]. 工矿自动化, 2025, 51(增1): 192-195.

[17] CHENG Qiang . Study on full filling pressure grouting treatment and effect evaluation in coal mine goaf[J]. Journal of Mine Automation, 2025, 51(S1): 192-195.

[18] ALEXEY L , VADIM K , IVAN U , et al. Theoretical approaches for modeling and calculating the consolidation of a composite weak bottom[J]. Transportation Research Procedia, 2022, 63: 938-945.

[19] JIA H W, YAN B X, YILMAZ E. A large goaf group treatment by means of mine backfill technology[J/OL]. Advances in Civil Engineering, 2021.DOI: 10.1155/2021/3737145.

[20] 孔德森, 吴绍娟, 马顺顺, 等 . 地下空间增层开挖支护桩与基桩工作特性模型试验研究[J]. 山东科技大学学报 (自然科学版), 2023, 42(6): 49-56.

[21] KONG Desen , WU Shaojuan , MA Shunshun , et al. Model test study on working characteristics of support piles and foundation piles during excavation of additional layers in underground space[J]. Journal of Shandong University of Science and Technology (Natural Science), 2023, 42(6): 49-56.

[22] 刘金砺 . 桩基础设计与基础[M]. 北京: 中国建筑工业出版社, 1990.

[23] 钱鸣高, 李鸿昌 . 采场上覆岩层活动规律及其对矿山压力的影响[J]. 煤炭学报, 1982(2): 1-12.

[24] QIAN Minggao , LI Hongchang . The movement of overlying strata in longwall mining and its effect on ground pressure[J]. Journal of China Coal Society, 1982(2): 1-12.

[25] 钱鸣高, 缪协兴, 许家林 . 岩层控制中的关键层理论研究[J]. 煤炭学报, 1996, 21(3): 2-7.

[26] QIAN Minggao , MIAO Xiexing , XU Jialin . Theoretical study of key stratum in ground control[J]. Journal of China Coal Society, 1996, 21(3): 2-7.

[27] 张华兴 . 开采沉陷预测的标准化[J]. 煤矿开采, 2014, 19(1): 1-20.

[28] ZHANG Huaxing . Standardization of mining subsidence prediction[J]. Coal Mining Technology, 2014, 19(1): 1-20.

[29] 邓喀中, 谭志祥, 张宏贞, 等 . 长壁老采空区残余沉降计算方法研究[J]. 煤炭学报, 2012, 37(10): 1601-1605.

[30] DENG Kazhong , TAN Zhixiang , ZHANG Hongzhen , et al. Research on calculating method of residual subsidence of longwall goaf[J]. Journal of China Coal Society, 2012, 37(10): 1601-1605.

[31] 中国煤炭建设协会 . 煤矿采空区建(构)筑物地基处理技术规范 GB51180—2016[S]. 北京: 中国计划出版社, 2016.

基金资助

国家自然科学基金项目(42572362)

山东省自然科学基金项目(ZR2021QE187)

山东省高等学校“青创人才引育计划”项目(ZXQT20221228001)