基于灰色系统的天津滨海区软弱地基沉降分析及预测

发布时间：2018-03-13 11:44

本文选题：灰色预测　切入点：软土地基　出处：《中国地质大学（北京）》2014年硕士论文　论文类型：学位论文

【摘要】：高速公路如何规避沉降问题一直是工程质量主要控制问题，而软土路基则是理论研究的重点。滨海道路对沉降要求高，软土路基沉降计算和预测是道路建设工程中急需解决的重要问题。本文以天津滨海区京津高速公路工程为依托，根据实际沉降资料，分析高速公路相关监测与地质资料，归纳分析影响沉降的主要因素和发展变化规律，为软土地基处理与公路施工提供理论研究基础，同时采用灰色模型来分析及预测软土地基沉降量。本文的主要研究成果如下： 1.本论文依据实际测得的数据，对软基变形的特点进行了讨论。填土路基中的软基变形隶属于平面应变的范畴，当前建立在一维固结理论基础上的沉降计算方法不能有效预测软基变形的问题。软土的塑流现象是造成软基变形的重要影响因素。 2.填土的速度是造成软弱地基变形现象另一重要的影响因素。合理有效地填土速度是保证高填方软基路堤安全施工的重要控制点，，可以直接影响路堤的稳定性、地基沉降的大小及其后续的发展方向。不合理的填土速度不但会增加工程完工后的沉降现象，还拖延工程后续施工步骤，进而拖延整个施工工程的质量与速度。 3.已有的规范不能有效且准确的预测软基沉降的相关数据，目前诸如指数曲线法、对数曲线法等传统方法对最终沉降的估算仅仅是建立在少量沉降数据的基础上的，其准确度不高，存在较大的误差。本论文使用的灰色预测法能够有效利用现有的所有沉降数据，具备较高的准确度，预测结构可信度更高。 4.本论文运用灰色预测模型较为准确的估算了软土地基的最终沉降量。利用该模型进行预测的首要条件是原始数据必须是等时（空）距的，我们为了得到这类型的原始数据，运用三次B样条函数对实际测得的沉降数据进行了插值，并运用插值数据进行沉降预测，预测结果符合预期，与实测值误差不超过10%。实践证明，灰色预测方法可行且有效。
[Abstract]:How to avoid the settlement of expressway has always been the main problem of engineering quality control, and the soft soil subgrade is the focus of theoretical research. The calculation and prediction of subgrade settlement in soft soil is an important problem in road construction engineering. Based on the Beijing-Tianjin Expressway Project in Tianjin Binhai area, based on the actual settlement data, the paper analyzes the relevant monitoring and geological data of expressway. The main factors affecting settlement and the law of development and change are summarized and analyzed to provide a theoretical basis for soft foundation treatment and highway construction. Meanwhile, grey model is used to analyze and predict the settlement of soft soil foundation. The main results of this paper are as follows:. 1. Based on the measured data, the characteristics of soft foundation deformation are discussed in this paper. The deformation of soft foundation in fill subgrade belongs to the range of plane strain. The settlement calculation method based on one-dimensional consolidation theory can not effectively predict the deformation of soft foundation. The plastic flow phenomenon of soft soil is an important factor that causes the deformation of soft foundation. 2. The velocity of fill is another important influence factor to the deformation of soft foundation. Reasonable and effective filling speed is an important control point to ensure the safety construction of high fill embankment, which can directly affect the stability of embankment. Unreasonable filling speed will not only increase the settlement phenomenon after the completion of the project, but also delay the subsequent construction steps of the project, and then delay the quality and speed of the whole construction project. 3. The existing codes can not effectively and accurately predict the relevant data of soft foundation settlement. At present, traditional methods such as exponential curve method, logarithmic curve method and other traditional methods for estimating the final settlement are only based on a small amount of settlement data. The grey prediction method used in this paper can use all the existing settlement data effectively and has higher accuracy and higher reliability of prediction structure. 4. In this paper, the final settlement of soft soil foundation is estimated accurately by using the grey prediction model. The primary condition of prediction by this model is that the original data must be isochronous (spatial) distance, in order to obtain this kind of original data, The cubic B-spline function is used to interpolate the actual settlement data, and the interpolation data is used to predict the settlement. The predicted results are in line with the expectation, and the error from the measured values is not more than 10. The practice shows that the grey prediction method is feasible and effective.
【学位授予单位】：中国地质大学（北京）
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U416.1

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