Research On Wear Prediction Of Shield Hob Based On Support Vector Machine

In the tunnel construction,the shield method has the characteristics of good quality,rapid progress,small impact on the existing urban rail traffic,and the safety of construction,so it has been developed rapidly in the construction of subway tunnel and underground pipeline construction.As a replacement part in shield construction,hob is costly and complex.If the replacement will cause the waste of resources,if the replacement is not timely,it will lead to the low driving efficiency,which will lead to the collapse of the knife plate and even the production accident.Therefore,it is of great significance to study the prediction of hob wear.For the wear of hob,it is basically based on experience,but frequent opening not only delays the construction period,but also increases the risk of construction.Therefore,it is necessary to study a more scientific and economical method for predicting the wear of hob.In this paper,a prediction method of hob wear based on support vector machine technology is studied.Through the shield driving force,the torque of the cutter disk,the speed of the jack,the speed of the cutter and the rotating speed of the cutter head,the abrasion of the shield hob is predicted.In engineering practice,it is generally believed that the relationship between the driving parameters can reflect the properties of the hob and reflect the wear state.After the deduction,the relation expression of the driving parameters related to the wear of the hob can be obtained.This paper derives a new relationship expression of the driving parameters,and simplifies the formula on the basis of the commonly used 17 inch and 19 inch hob.After deriving the correlation between the driving parameters and the hob wear,the main driving parameters are extracted and used as the characteristic variables of support vector machines,and a support vector machine model is established.The prediction program of hob wear is designed based on the derived tunneling parameter formula,T test method and support vector machine model.Finally,combined with engineering practice,the hob wear identification system based on support vector technology is applied to engineering to verify and detect its prediction ability.In the application,the support vector machine model shows good judgment.The common evaluation index shows that the support vector machine technology has good prediction effect on the wear prediction of the hob in the shield.