GM(1,1)模型与指数模型在基桩沉降预测中的应用

Application of GM(1,1) Model and Index Curve Model in the Forecast of Foundation Pile Settlement

以某大型基桩的沉降预测为例,利用灰色系统理论的GM(1,1)与Aeax曲线模型进行基桩在外荷载作用下沉降量的预测。结果表明:两种模型对于呈指数变化规律的系统能获得较好的预测结果;两种模型对基桩累计沉降的预测符合工程实际,对各级荷载作用下的本级沉降预测不够合理。对两种模型关系的研究表明,两者有内在联系,都属指数曲线预测模型,且指数曲线Aeax预测模型比GM(1,1)模型应用起来更简单,方便。

Taking the settlement forecast of a certain large foundation pile as an example, the methods of gray forecast GM(1,1) model and index curve Aeax model are presented and are used to predict the settlement of the foundation pile under the action of the external load. The results show that satisfactory results may be obtained if they are used to predict the system which changes with index curve rules and the accumulative total settlement of a pile can be predicted with the two forecast models accurately, but each level settlement cannot be predicted reasonably under each level of load. From the research, some conclusions can be drawn that the two forecast models both belong to index curve forecast model, and index curve Aeax forecast model is simpler and more convenient than GM(1,1) forecast model in application.