管道结构垂向—侧向耦合管土作用机理性试验研究

钢制悬链线式立管的触地段与海床会发生频繁的相互作用，对管道的安全性影响很大。首先探索干土环境下管土作用的机理有助于更好地理解真实海况下管道—湿土作用规律。试验测试是研究管土作用最可信最直接的手段。进行了垂向及侧向管土作用机理性试验，根据土体抗剪强度验证了试验中相互作用机理与管道尺寸的无关性。研究了不同运动速度对土体反力的影响，发现运动速度对垂向及侧向管土作用均存在一定的放大效应，而垂向低速工况下放大效应不明显；接着分别研究了垂向与侧向管土作用的规律，分析了土体反力变化的成因，最后针对管土垂向—侧向的耦合效应进行研究，发现不同的垂向深度会极大地影响侧向管土作用。为后续的管道—含水土体相互作用试验奠定基础，也可为陆上管土作用相关研究提供参考与建议。

Experimental study on the vertical-lateral coupling pipe-soil interaction of pipelines structure

The contact section of the steel catenary riser will frequently interact with the seabed, which has a great impact on the safety of the pipeline. First, exploring the law of pipe-soil interaction in dry soil environment is helpful to understand the law of pipe-wet soil interaction under real sea conditions. Experimental research is the most credible and direct method to study pipe-soil interaction. Vertical and lateral pipe soil tests are conducted. The shear strength of the soil is used to verify the independence of the pipe size in the tests. The influence of different speeds on soil reaction force in pipe-soil interaction is studied. It is found that the velocity has an amplifying effect on both the vertical and lateral pipe-soil interaction, but the amplification effect is not obvious in the vertical low speed condition. Then, the law of vertical and lateral pipe-soil interaction and the cause of soil reaction force change are studied respectively. Finally, the vertical-lateral coupling effect of pipe-soil is studied. It is found that different vertical depths will greatly affect the lateral pipe-soil interaction. The research lays the foundation for subsequent pipeline-wet soil interaction experiments, and also provides references and suggestions for the related researches on the pipe-soil interaction on land.