极端波浪荷载作用下近海桥梁下方海床瞬态液化稳定性研究

发布时间：2018-02-20 08:01

本文关键词： 极端波浪 RANS方程海床液化箱梁　出处：《岩土力学》2017年07期 　论文类型：期刊论文

【摘要】：为研究极端波浪荷载作用下近海桥梁下方密实海床的瞬态液化稳定性,通过求解RANS方程和Biot方程,建立了极端波浪作用下箱梁下方密实海床动力响应的有限元数值模型。将该模型与以往试验结果对比,验证了该模型的准确性,基于此模型进一步研究了极端波浪作用下箱梁周围的波浪压力场分布及波浪特性、淹没深度对桥梁下方密实海床瞬态液化稳定性的影响。研究结果表明:处于淹没状态的箱梁对周围波压场影响较大,箱梁迎浪侧密实海床的瞬态液化深度大于背浪侧,液化深度幅值距离箱梁1/10~1/8波长范围内达到最大;随着波高与波浪周期的增大,箱梁左、右两侧密实海床瞬态液化深度均增大;在迎浪侧,当箱梁刚好完全被淹没时,海床瞬态液化深度最大,而在背浪侧,随着淹没深度增加,箱梁下方海床趋于安全。其研究结果可为跨海桥梁安全性分析提供参考。
[Abstract]:In order to study the transient liquefaction stability of the dense seabed beneath the offshore bridge under extreme wave loads, the RANS equation and the Biot equation are solved. The finite element numerical model of the dynamic response of the dense seabed under the extreme wave action is established, and the accuracy of the model is verified by comparing the model with the previous experimental results. Based on this model, the wave pressure field and wave characteristics around the box girder under extreme wave action are further studied. The influence of submerged depth on the transient liquefaction stability of dense seabed under the bridge. The results show that the submerged box girder has a great influence on the surrounding wave pressure field, and the transient liquefaction depth of the dense seabed is greater than that of the back wave side. The amplitude of liquefaction depth reaches the maximum within the wavelength range of 1 / 10 / 1 / 8 of box girder; with the increase of wave height and wave period, the transient liquefaction depth of the box girder increases on the left and right sides of the dense seabed, and on the wave side, when the box girder is completely submerged, The depth of transient liquefaction of the seabed is the largest, but on the side of the back wave, the seabed beneath the box girder tends to be safe with the increase of the submerged depth. The results of the study can provide a reference for the safety analysis of the cross-sea bridge.
【作者单位】：西南交通大学桥梁工程系;
【基金】：国家自然科学基金(No.51178397)~~
【分类号】：U441

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