梁板式桩筏基础现场测试分析

Field test of piled beam-slab foundation

风力发电工程是我国乃至世界可持续发展之路的重要一步,而梁板式风机基础是陆上风机基础的一种新型形式,梁板式风机基础的研究正受到学术界和工程领域的广泛关注。基于江苏射阳港风电项目,通过在风机基础底板下埋设土压力盒,桩内布设钢筋计,测算风机基础从风机施工至正常运行过程中的基底土压力分布和桩顶轴力。重点讨论风机处于施工过程中和正常运行状态下桩顶轴力的变化规律,分析桩土分担比,并将现场试验得到的基础内力与实际设计方法计算所得基础内力进行对比验证。结果表明,风机运行前,竖向荷载主要由内圈桩承担,风机运行后,外圈桩承担荷载增加,内圈桩承担荷载减小;风机运行后土体承担荷载较大,目前的设计方法不考虑土体的承载作用,计算结果偏于安全。

The project of wind power generation is an important step of the sustainable development path of China or even the world. Piled beam-slab foundation of wind generating set is a new form of the foundation for wind turbine on land, the research on which is attracting broad attention in academic and engineering fields. Through installing earth pressure cells under the baseboard and reinforcement meters in the piles, the test, based on the wind turbine project at Sheyang port in Jiangsu province, measures the soil pressure under the foundation and the axial force at the top of piles when the wind turbine is under construction and working normally The research mainly focuses on the change rules of the axial force at the top of piles of the wind turbine piled beam-slab foundation under construction condition and working condition and the analysis of the load sharing percent of piles and soil. The contrastive analysis of the internal forces between the field test and actual design calculation is also carried out. The results show that the piles bear most of the load before the wind turbine running; piles inside bear less load and piles outside bear more after the wind turbine running. The soil bears large percentage of load when the wind turbine is working; so the current design method which doesn＇t consider the bearing capacity of soil makes the result safer.