Applying stiffness migration method,a 3D finite element mechanical model is established to simulate the excavation and advance processes.By using 3D nonlinear finite element method,the tunnel boring machine(TBM) excavation process is dynamically simulated to analyze the stress and strain field status of surrounding rock and segment.The maximum tensile stress of segment ring caused by tunnel construction mainly lies in arch bottom and presents zonal distribution.The stress increases slightly and limitedly in the course of excavation.The maximum and minimum displacements of segment,manifesting as zonal distribution,distribute in arch bottom and vault respectively.The displacements slightly increase with the advance of TBM and gradually tend to stability.
Temperature control,which is directly responsible for the project quality and progress,plays an important role in high arch dam construction.How to discover the rules from a large amount of temperature control information collected in order to guide the adjustment of temperature control measures to prevent cracks on site is the key scientific problem.In this paper,a mathematic logical model was built firstly by means of a coupling analysis of temperature control system decomposition and coordination for high arch dam.Then,an analysis method for temperature control information was presented based on data mining technology.Furthermore,the data warehouse of temperature control was designed,and the artificial neural network forecasting model for the highest temperature of concrete was also developed.Finally,these methods were applied to a practical project. The result showed that the efficiency and precision of temperature control was improved,and rationality and scientificity of management and decision-making were strengthened.All of these researches provided an advanced analysis method for temperature control in the high arch dam construction process.
ZHONG DengHua,ZHAO ChenSheng & REN BingYu Department of Hydraulic and Hydroelectric Engineering,School of Civil Engineering,Tianjin University,Tianjin 300072,China
A complete scheme for solving the key scientific problems of how to make concrete sequence placement scheme of high arch dam reasonable and feasible and how to meet the need of construction process was presented.First,based on a coupling analysis of concrete sequence placement system of high arch dam,a mathematical model considering complex construction constraints was established.Second,a multi-scheme computational analysis method for concrete sequence placement of high arch dam was proposed based on dynamic simulation.Third,a multi-scheme evaluation method for concrete sequence placement was put forward based on analytic hierarchy process.Fourth,feedback guidance for progress control and management in the high arch dam construction process was proposed.Finally,these methods were applied to a practical project to show that the methods can analyze and evaluate multi-scheme for concrete sequence placement of high arch dam effectively,optimize the process of dam concrete sequence placement,and recommend engineering measures.These methods provide new theoretical principles and technical measures for real-time progress control in the high arch dam construction.
ZHONG GuiLiang,REN BingYu & TONG DaWei Department of Hydraulic and Hydroelectric Engineering,School of Civil Engineering,Tianjin University,Tianjin 300072,China
