滑坡时间预测预报目前主要以滑坡最终破坏的时间为目标函数,但对于变形特征为阶跃型的滑坡却难以准确地预测其破坏时间。为此,提出以位移作为此类滑坡时间预报的目标函数。将滑坡位移分解为蠕变位移和波动位移,采用二次移动平均法分别提取,然后采用多项式拟合和灰色GM(1,1)模型分别对蠕变位移和波动位移进行预测,最后将两部分预测位移相加得到滑坡预测的总位移。以典型阶跃型位移特征滑坡——三峡库区八字门滑坡为例,运用其位移监测数据进行验证,并对多模型预测结果进行对比分析,结果表明,该位移预测模型预测精度良好,能较好地预测阶跃型位移特征滑坡位移。
Recently, the landslide forecast is mainly focused on the prediction of the time when the landslide fails. But it is difficult to predict the failure time accurately for the landslides whose displacement shows step-style. Therefore, the displacement prediction is proposed as the target function for this kind of landslide. Firstly, the landslide displacement is divided into two parts, creepage displacement and fluctuation displacement, which are picked up by the twice moving average method. Then, the polynomial fit and grey GM (1, 1) model are applied to predict the creepage displacement and fluctuational displacement separately. Finally, the two parts of forecasted displacement are added up and the total landslide displacement is obtained. A typical step-style landslide in the Three Gorges Reservoir, Ba Zhimen landslide is taken as study case. This model is verificated with the monitoring data and compared with the predicted results of other forecast models. It is observed that this forecast model can provide a good predicted displacement of the landslides with step-style displacement characteristics.