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Numerical simulation of wave-current load on high pile cap foundation
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摘要: 为研究高桩承台基础在波流作用下的荷载时程特点和压力分布规律，开展某跨海大桥桩-承台复合基础的数值模拟研究。根据Stokes二阶波理论进行数值水池造波，采用雷诺平均应力方程（RANS）求解流体运动方程，计算得出3种淹没系数（0~1）下高桩承台基础的各部分水动力时程及其表面压力分布；应用流体体积函数（VOF）追踪液面形态模拟波浪形态时程。研究结果表明：（1）淹没系数较大时，承台水平力较大且主要来自波流联合作用，尾流区绕射波浪会产生负向水平力和负向浮托力，承台迎波面及顶面后方存在压力波动极值区；（2）随着淹没系数的降低，承台水平力减小，水平力主要以波浪拍击力为主，竖向浮托力、单桩水平力随之增加，尾流区绕射效应降低，承台压力极值波动区缩小直至消失；（3）桩基正向水平力最大值出现在边列最后排桩；负向水平力最大值出现在中列最后排桩。研究所得总力时程和压力分布规律可为优化结构设计提供参考。Abstract: In order to study the load time history characteristics and pressure distribution law of high pile cap foundation under wave current, the pile cap composite foundation of a sea crossing bridge is numerically simulated. According to Stokes second-order wave theory, wave generation in numerical pool is carried out, and Reynolds averaged Navier stokes equation (RANS) is used to solve the fluid motion equation. The hydrodynamic time history and surface pressure distribution of each part of high pile cap foundation under three submergence coefficients in the range of 0~1 are calculated. The volume of fluid function (VOF) is used to track the liquid surface shape and simulate the wave shape time history. The results show that: (1) When the submergence coefficient is large, the horizontal force of the cushion cap is large and mainly comes from the combined action of wave and current; the diffracted waves in the wake area will produce negative horizontal force and negative buoyancy force; there is an extreme pressure fluctuation region on the upstream and downstream of the cushion cap. (2) With the decrease of submergence coefficient, the horizontal force of cushion cap decreases, and the horizontal force is mainly wave beating force; the vertical buoyancy force and the horizontal force of single pile increase accordingly; the diffraction effect in the wake region is reduced; the fluctuation area of extreme pressure of bearing platform is reduced until it disappears. (3) The maximum positive horizontal force of the pile foundation appears in the last row of piles on the side column; the maximum negative horizontal force appears in the last row of piles in the middle column. The research on the total force history and pressure distribution law can provide a reference for optimizing structural design.
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Key words:
- wave current force /
- high pile cap /
- time history analysis /
- pressure distribution
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图 2 计算域尺寸、边界条件及计算网格
Figure 2. Calculation domain size and boundary condition computation grid
图 5 Cs=1.00工况下采用不同网格方案的计算值与试验值对比
Figure 5. Comparison of calculation results and test results of different schemes (Cs=1.00)
图 6 Cs=0.55工况下采用网格方案5计算数据与试验值的对比
Figure 6. Comparison between calculation results of grid scheme 5 and test results (Cs=0.55)
图 7 不同工况下承台水平力时程
Figure 7. Horizontal force time history of bearing platform under different working conditions
图 8 不同工况下承台浮托力时程
Figure 8. Buoyancy time history of bearing platform under different working conditions
图 9 不同工况下群桩总水平力时程
Figure 9. Total horizontal force time history of pile group under different working conditions
图 10 群桩总力正向（负向）最大时各单桩贡献系数
Figure 10. Contribution coefficient of each single pile when the positive force (negative force) is maximum
图 11
$ {C_{\text{s}}} $ =1.00，波浪形态时间历程（单位: m）Figure 11. Time history of wave form (
$ {C_{\text{s}}} $ =1.00) (unit: m)
图 13
$ {C_{\text{s}}} $ =0，波浪形态时间历程（单位: m）Figure 13. Time history of wave form (
$ {C_{\text{s}}} $ =0) (unit: m)
图 12
$ {C_{\text{s}}} $ =0.55，波浪形态时间历程（单位: m）Figure 12. Time history of wave form (
$ {C_{\text{s}}} $ =0.55) (unit: m)表 1 波浪要素及计算工况
Table 1. Wave elements and working conditions
淹没系数 静水深度/m 波高/m 周期/s 波长/m 静水流速/（m·s−1） Cs=1.00 22.30 6.9 8.3 96 3.64 Cs=0.55 18.93 Cs=0 14.80 
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表 2 不同网格方案参数
Table 2. Parameters of different grid schemes
最大网格尺寸/m 单元数/个 计算域范围 Z/Y向网格 X向网格 承台-桩表面网格 网格方案1 4 6 4 172 785 网格方案2 2 6 2 297 177 网格方案3 2 6 1 346 513 网格方案4 1 3 0.5 1 015 335 网格方案5 1 3 0.25 2 005 582 网格方案6 0.5 1 0.1 5 402 545
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表 3
$ {C_{\text{s}}} $ =1.00计算结果对比Table 3. Comparison of calculation results (
$ {C_{\text{s}}} $ =1.00)单位：kN 方案 承台水平力 承台浮托力 桩基最大力 单桩最大力 网格方案1 7 296.22 3 154.68 5 698.01 741.48（Z8） 网格方案2 7 250.34 3 472.13 5 445.38 705.38（Z4） 网格方案3 6 993.28 3 766.94 4 876.31 540.78（Z10） 网格方案4 7 006.78 3 685.23 4 638.88 546.02(Z10) 网格方案5 7 182.15 4 206.10 4 461.20 556.40（Z3） 网格方案6 7 173.45 4 216.13 4 213.40 543.23（Z3） 试验数值 6 768.5 4 616.1 4 393.7 507.4（Z3）
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[1] 方庆贺. 跨海近岸桥梁极端波浪作用研究[D]. 哈尔滨: 哈尔滨工业大学, 2012. FANG Qinghe. Study on extreme wave loads of coastal highway bridges[D]. Harbin: Harbin Institute of Technology, 2012. （in Chinese） [2] 项海帆. 21世纪世界桥梁工程的展望[J]. 土木工程学报,2000,33(3):1-6 XIANG Haifan. Prospect of world’s bridge projects in 21st century[J]. China Civil Engineering Journal, 2000, 33(3): 1-6. (in Chinese) [3] 黄雯, 冯谊武, 张海龙. 波浪作用下的群桩受力及优化布置[J]. 桥梁建设,2016,46(3):51-56 HUANG Wen, FENG Yiwu, ZHANG Hailong. Mechanical properties and optimal arrangement of group piles acted by wave forces[J]. Bridge Construction, 2016, 46(3): 51-56. (in Chinese) [4] 房忱, 李永乐, 秦顺全, 等. 中、美、英规范关于跨海桥梁桩基波浪力的对比[J]. 桥梁建设,2016,46(6):94-99 FANG Chen, LI Yongle, QIN Shunquan, et al. Comparison of wave forces of pile foundations for sea-crossing bridges provided in Chinese, American and British codes[J]. Bridge Construction, 2016, 46(6): 94-99. (in Chinese) [5] MORISON J R, JOHNSON J W, SCHAAF S A. The force exerted by surface waves on piles[J]. Journal of Petroleum Technology, 1950, 2(5): 149-154. doi: 10.2118/950149-G [6] WEI K, YUAN W C, BOUAANANI N. Experimental and numerical assessment of the three-dimensional modal dynamic response of bridge pile foundations submerged in water[J]. Journal of Bridge Engineering, 2013, 18(10): 1032-1041. doi: 10.1061/(ASCE)BE.1943-5592.0000442 [7] MACCAMY R C, FUCHS R A. Wave forces on pliles: a diffraction theory[R]. Corps of Engineers Washington DC Beach Erosin Board, Ojio: Us Army Coastal Engineering Research Center, 1954. [8] BHATTA D D, RAHMAN M. On scattering and radiation problem for a cylinder in water of finite depth[J]. International Journal of Engineering Science, 2003, 41(9): 931-967. doi: 10.1016/S0020-7225(02)00381-6 [9] 杜修力, 赵娟, 赵密. 大直径深水圆柱结构动水压力的时域算法[J]. 土木工程学报,2012,45(增刊1):316-320 DU Xiuli, ZHAO Juan, ZHAO Mi. A time-domain method for the hydrodynamic pressure on deep-water cylindrical structure with large diameter[J]. China Civil Engineering Journal, 2012, 45(Suppl1): 316-320. (in Chinese) [10] 张胡, 刘清君, 王登婷. 大尺度结构波浪力计算研究[J]. 水道港口,2018,39(2):151-156, 187 ZHANG Hu, LIU Qingjun, WANG Dengting. Research on calculation of wave forces acting on the large scale structure[J]. Journal of Waterway and Harbor, 2018, 39(2): 151-156, 187. (in Chinese) [11] 邓莎莎, 沈火明, 刘浪, 等. 基于绕射理论的大尺度桥墩波浪力计算方法[J]. 西南交通大学学报,2018,53(2):266-271 DENG Shasha, SHEN Huoming, LIU Lang, et al. Research of calculation method for wave forces acting on large-scale bridge piers based on diffraction theory[J]. Journal of Southwest Jiaotong University, 2018, 53(2): 266-271. (in Chinese) [12] 兰雅梅. 桩基结构物的波-流作用力研究[D]. 上海: 上海交通大学, 2006. LAN Yamei. Study on hydrodynamic loads on piled structures in wave-current combination[D]. Shanghai: Shanghai Jiao Tong University, 2006. （in Chinese） [13] 魏凯, 周聪, 徐博. 跨海桥梁高桩承台波浪冲击荷载概率模型[J]. 工程力学,2020,37(6):216-224 WEI Kai, ZHOU Cong, XU Bo. Probability model of wave impact load on the elevated pile cap for sea-crossing bridges[J]. Engineering Mechanics, 2020, 37(6): 216-224. (in Chinese) [14] 仇正中, 赵东梁. 中马友谊大桥主桥承台波浪荷载数值模拟研究[J]. 施工技术,2019,48(5):5-8 QIU Zhengzhong, ZHAO Dongliang. Study on numerical simulation of wave load on main bridge foundation cap for China and Maldives friendship bridge[J]. Construction Technology, 2019, 48(5): 5-8. (in Chinese) [15] 刘正浩, 万德成. 波流作用下海上固定式风机基础的水动力性能数值模拟[J]. 江苏科技大学学报(自然科学版),2017,31(5):555-560,566 LIU Zhenghao, WAN Decheng. Numerical study of hydrodynamic performance of wind turbine foundation under wave-current combinations[J]. Journal of Jiangsu University of Science and Technology (Natural Science Edition), 2017, 31(5): 555-560,566. (in Chinese) [16] 董伟良, 诸裕良, 胡金春, 等. 跨海桥梁大尺寸承台波浪力数值模拟研究[J]. 水道港口,2020,41(1):50-57 DONG Weiliang, ZHU Yuliang, HU Jinchun, et al. Numerical simulation study of wave load on large-size cap of cross-sea bridge[J]. Journal of Waterway and Harbor, 2020, 41(1): 50-57. (in Chinese) [17] 金小凯, 陈锦剑, 廖晨聪. 波浪荷载对单桩承载力影响的水槽模拟试验研究[J]. 上海交通大学学报,2021,55(4):365-371 JIN Xiaokai, CHEN Jinjian, LIAO Chencong. Wave flume simulation experiment on influence of wave load on bearing capacity of monopile[J]. Journal of Shanghai Jiao Tong University, 2021, 55(4): 365-371. (in Chinese) [18] 徐博, 魏凯. 基于RANS的跨海桥梁高桩承台波浪作用数值模拟[J]. 铁道标准设计,2019,63(12):79-84 XU Bo, WEI Kai. Numerical simulation of wave forces on elevated pile cap of sea-crossing bridges based on RANS[J]. Railway Standard Design, 2019, 63(12): 79-84. (in Chinese) [19] 刘桦, 王本龙, 薛雷平, 等. 桩基承台结构的波流力研究进展[J]. 应用数学和力学,2013,34(10):1098-1109 LIU Hua, WANG Benlong, XUE Leiping, et al. Recent progress in wave-current loads on foundation structure with piles and cap[J]. Applied Mathematics and Mechanics, 2013, 34(10): 1098-1109. (in Chinese) [20] 张洪翔. 波浪—流联合作用下结构—海床耦合系统的动力响应分析[D]. 南京: 南京航空航天大学, 2019. ZHANG Hongxiang. Dynamic response analysis of structure-seabed coupled system under wave-current[D]. Nanjing: Nanjing University of Aeronautics and Astronautics, 2019. （in Chinese） -
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