Papers by Author: Ya Wen Liu

Abstract: In order to make the performance evaluation of highway asphalt pavement more scientific and reasonable, carrying out pavement maintenance management is more necessary. Taking advantage of excellent adaptability of neural network technology to deal with nonlinear mapping problem, a breakage condition evaluation model based on radial basis function (RBF) neural network is presented. This model considers four main affecting factors including pavement rut condition, crack condition, pit slot condition and repair condition. Certain number of sample data is chosen to train and simulate the RBF neural network model. The tests results, accordant with expectation, indicate that the model is qualified for practical engineering applications.

Abstract: In order to provide a theoretical basis for the alignment regulation of prestressed box-girder bridge with corrugated webs, so that the control for alignment can be more targeted. Optimization model of alignment regulation for cantilever constructed pre-stressed box-girder bridge with corrugated webs is proposed based on optimization principle. The sensitivity of alignment error, transverse stress of bottom plate and transverse deformation of corrugated web with respect to design parameters is analyzed during three classical construction stages. The results indicate that the concrete density, concrete elastic modulus, longitudinal and transverse pre-stress are key control parameters of alignment regulation; alignment error is not sensitive to the change of uniformly distributed temporary loads; the cantilever state at one fourth span is most sensitive to the change of design parameters.

Abstract: Some secondary effect introduced by corrugated configuration of corrugated web was studied and formulas were proposed. The deduction for these formulas was resolved into two steps. Step I: to solve the behavior of whole corrugated web by considering it as an orthotropic plate; Step II: to solve the secondary effect according to the shape parameters of corrugation based on the result of Step I. Subsequently, a numerical experiment was designed to validate the analytical work with the help of finite element package ANSYS taking material nonlinearity into consideration. The results obtained from numerical and analytical methods show good agreement. It indicates that the formulas proposed in this paper are convenient and efficient. This research deals with this secondary effect for the first time; more studies are needed for the effect on local buckling of corrugated webs.