描述PHC桩抗拔荷载-位移曲线的Weibull数学模型

为加深对PHC桩的认识和推广它的应用，基于3个场地中共11根现场试验PHC抗拔桩的实侧资料的优化拟合，对PHC桩的一些抗拔性状进行了研究。针对抗拔PHC桩的承载特性，选用了Weibull 数学模型描述PHC抗拔桩的上拔荷载-上拔位移曲线，对11根现场试验桩的拟合表明，Weibull 模型的拟合精度高，相关系数 为0.98877~0.99963，平均0.99782；该模型对抗拔PHC桩的拟合效果比指数模型、双曲线模型的都要好；基于该数学模型的PHC桩上拔荷载的计算值与实测值的误差一般为 ；基于Weibull 模型的拟合曲线，某两工程中PHC桩上拔荷载达到极限状态时的上拔位移量一般在5mm~17mm之间；基于Weibull 模型的拟合结果，对PHC桩抗拔荷载与抗压荷载、PHC桩与钢管桩进行了比较。结果表明，本文选用的Weibull 数学模型针对抗拔PHC桩上拔荷载-上拔位移曲线的拟合是较为精确的和可靠的，PHC桩是一种较为优越的桩型。

Study on Weibull mathematical model fitting uplifting load versus uplifting displacement curve of PHC pile

In order to understand PHC pile profoundly and extend its application, based on optimized fitting of actual measurement data of 11 field testing piles in 3 sites, some uplift characteristics of PHC pile were studied.. Aiming at the bearing characteristics of PHC pile, Weibull mathematical model was selected and optimized fitting analysis of uplift load versus uplift displacement curves was carried out. The fitting results of 11 field testing piles with the model showed that the fitting precision was high, the correlativity coefficients R was 0.98877~0.99963, the average value was 0.99861.The fitting effect with the model was better than the hyperbolic model and exponential model. The error between calculation value and field measure value of uplifting load of PHC piles based on fitting equations was ; the uplift displacement of PHC piles was 5mm~17mm in certain two engineering when uplift reach ultimate state based on fitting curves; comparison between uplift load and compression load of PHC pile, between PHC pile and steel pipe pile was carried out based on fitting results. The following conclusions can be drawn that the Weibull mathematical model is accurate and credible for fitting of uplift load versus uplift displacement curves of PHC piles and PHC pile is a excellent pile.