复合地层盾构刀具磨损分析与预测

盾构机在复合地层中进行掘进时，刀具磨损严重，易发生偏磨，是制约土压平衡盾构机长距离高效掘进的重要因素。通过气压开仓和常压开仓技术，对深圳地铁9号线区间隧道盾构刀具进行现场磨损监测，分析了不同类型刀具在复合地层中的磨损规律，回归得到了不同类型刀具的磨损系数，并据此推算了盾构机在类似地层条件下的最远掘进距离。为准确预测盾构机掘进过程中刀具磨损情况，文章利用遗传算法优化BP神经网络模型对刀具磨损进行了分析，模型综合考虑了盾构机掘进速度、推力、扭矩等影响因素，预测结果与实测值接近。研究成果可为类似地层条件下的实际工程中盾构机的刀具磨损量、最长掘进距离等预测提供理论支持，对实际施工有一定指导作用。

Analysis and predication of shield cutters wear in mixed ground

In mixed ground, one of the most difficult problem of shield machine tunneling is severe wear and eccentric wear of cutters. This is fundamentally critical to ensure the shield machine to advance distantly in mix-face ground. The wear quantity of shield cutters used in shield tunnel section of Shenzhen metro line 9 was monitored. By analyzing the monitoring data of different types of cutters, the fitting expression of cutters wear to advancing distance was established and the longest advancement distance of the shield machine was calculated. Based on genetic algorithms optimizing BP neural network, a modeling prediction method of cutter wear was established and the predicted results are close to the measured results, which may provide theoretical basis for estimating the wear of cutters and longest advancement distance in similar stratum. The research conclusion is helpful for shield machine selection and engineering construction with similar geotechnical conditions.