抗拔桩极限承载力预测模型研究

发布时间：2018-01-09 04:16

本文关键词：抗拔桩极限承载力预测模型研究　出处：《南昌航空大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着我国国民经济的快速发展,土木工程建设方兴未艾,深基础的应用范围越来越广泛,桩基础在工程建设中发挥着十分重要的作用,其中的抗拨桩普遍应用于地下抗浮结构物、高耸而轻型的结构物、深基坑开挖以及膨胀土地区等。如何正确预测抗拔桩的承载能力,保证抗拔桩的安全使用。在此背景之下,本文主要进行以下几个方面的工作:(1)对桩基础的发展历史进行阐述,总结抗拔桩的研究现状,包括现场试验研究、模型试验研究和极限承载力计算等。(2)介绍抗拔桩基础的理论研究。在相关参考文献的基础上分析抗拔桩的破坏形态、抗拔桩和承压桩荷载传递机理的异同和抗拔桩承载力的计算方法。(3)根据桩基现有的技术规范,所计算的值往往偏于保守,造成资源的浪费和工程成本的提高。对此,本文在考虑了桩身自重的情况下,通过对折减系数进行调整以估算钻孔灌注桩抗拔承载力。(4)在静载荷有限的实验数据的背景下,利用灰色模型新陈代谢法取四组不同的数据对残差值进行预测,确定了残差值最小,精确度最高的数据组,优化了灰色预测过程中对原数据的选取。(5)根据三根桩S/Q-S的直线拟合图可以清楚的看出每段的直线斜率在不断减小,即预测的数据点越多预测的抗拔桩破坏荷载也越大。(6)根据折减系数法得到三根桩的极限承载力对比工程中静载荷法得到的极限承载力,可以得出由于静载荷试验设备有限,工程中对承载力估计偏于保守。
[Abstract]:With the rapid development of our national economy, just unfolding civil engineering construction, deep foundation is applied more and more widely, pile foundation plays a very important role in the engineering construction, the anti pulling pile is widely used in underground anti floating structures, lightweight structures towering, deep excavation and expansive soil area. How to correctly predict the bearing capacity of uplift piles, ensuring the safe use of the uplift pile. Under this background, this thesis mainly focuses on the following work: (1) the development history of the pile foundation are expounded, summarizing the research status of uplift piles, including field tests, bearing capacity calculation model experimental study and limit. (2) the theoretical study on uplift pile foundation. The failure pattern of pile based on related references, similarities and differences between the transfer mechanism of pile and pile bearing load resistance and bearing capacity of uplift piles The calculation method. (3) according to the technical specification of existing pile foundation, tends to be conservative values calculated, resulting in a waste of resources and increases the cost of project. In this regard, considering the pile gravity, adjusted to estimate the uplift bearing capacity of Drilled Grouting Pile by fold reduction coefficient (4. The experimental data of static load) in the limited context of the four different groups of data on the residual value is predicted by the grey model method to determine the residual value of The new supersedes the old., minimum data set the highest accuracy, optimize the selection of the original data of grey prediction process. (5) according to the linear fitting chart of three piles S/Q-S can each section of straight slope decreases constantly see clearly, the more predicted data point prediction of uplift pile failure load is greater. (6) according to the reduction coefficient of three pile ultimate bearing capacity in the static load is obtained by the method of comparison of Engineering The ultimate bearing capacity can be obtained because the static load test equipment is limited, and the estimation of the bearing capacity is conservative in the project.

【学位授予单位】：南昌航空大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU473.1

【参考文献】