风电安装平台插桩过程的试验与理论研究

针对风电安装平台在多层土中的插桩过程,通过现场取样测试获取土壤的物理参数,并通过插桩试验得到其平均插桩深度,以此建立插桩过程的数值模型,对插桩阻力与深度的变化规律以及土壤的流动失效机制进行了研究。结果表明,经验法选取土壤弹性模量与实际相差较大,试验测出的平均插桩深度为7.3m;数值结果与试验结果吻合良好,证明了理论模型的正确性;土壤发生了表面隆起、空腔形成、壁面坍塌和土壤回流四种失效模式。

Experimental and Theoretical Investigations on Penetration Processof Offshore Wind Turbine Installation Platform

Experimental and theoretical investigations on the penetration into multilayer soil were presented for some offshore wind turbine installation platform. The soil physical parameters of the penetration area were obtained by the field experiments. The average penetration depth was evaluated according to the penetration test of the platform under 10000t loading. Then, numerical model of this penetration process was proposed. Finally, distributing rules of the penetration resistance-depth and mechanisms of the soil flow failure were investigated. The results showed that, soil elastic modulus evaluated by empirical method differed greatly from its real value. The tested average penetration depth was 7.3m. The numerical result agreed well with corresponding experimental value, proving the accuracy of the theoretical model. The penetration resistance first increased fast, then increased linearly with a low speed; As the spudcan approached the interface between 1# layer and 2# layer, it deceased slightly, and then increased fast; When the spudcan approached the interface between 2# layer and 3# layer, the resistance suddenly changed, and then increased sharply. Failure modes such as surface heave, cavity formation, wall collapse and soil back-flow appeared in the soil.