Research On Visual Simulation Of Face Rockfill Dam Construction Process

The concrete face rockfill dam (CFRD) is one of the most widespread using dams,which needs long-term and systematic engineering as it is affected by many factors such as material production and allocation, construction road layout, construction technology as well as external environment etc. The great concern of engineers is how to study such a huge systematic engineering and work out a strict and appropriate construction plan. Computer simulation technology, which is based on systematic internal logic and mathematical relation, can set up simulation models according to the actual systematic processes and behaviors, which can aid engineers to realize and implement complicated system, simultaneously the system can be optimized according to its law. Based on that, the construction process of CFRD is simulated by computer simulation technology in this paper.Under a certain material field circumstances and following the basic principal of material distribute, dynamic linear programming model of earthwork allocation is built to calculate the lowest cost of the whole distribution process when considering filling process, digging process, material matching, transit depot restrict and other factors. Different earthwork allocation volume in different periods is calculated by adopting pure-line method, that is, the lowest cost allocation plan, which can be applied to the practical project.The transportation modal is established by adopting random services circular queuing theory on the basis of considering the randomicity of the runtime of excavation and transportation equipments, layout features of junction roads, and the queuing process of loading service to simulate each aspect of the whole transportation processes. Material supply line, which includes feeding areas, reception areas, roads, mechanical equipments and etc., can be determined by the calculation results; the excavation and transportation equipments of each supply line can be deployed by transportation models and then the transportation process on the dam of each equipment is simulated, therefore, the transportation condition can be analyzed Some constraint conditions like construction sequence of adjacent areas of CFRD, rainfall, daily maximum rise height etc are taken into consideration, the placement intensity of the dam can be computed in accordance with the apply line and accessory project of mechanical equipments provided by the system; by considering flow operation and sequential operation, dam surface filling model can be established through applying discrete event system simulation method to simulate the construction process, hence the entire construction process, intensity and mechanical equipments utilization can be revealed.The three-dimensional dynamic visualization system simulation mechanism based on simulation data is studied to reflect the simulation results intuitively and synchronously. Different modeling methods like terrain modeling, static surface modeling, and dynamic dam modeling are applied in different structures. Based on the engine frame roaming function, collision detection technology, graphical interface, and construction information database are introduced to make the system more friendly and naturally.Taking the CFRD of Hekoucun as actual project, a set of construction process visualization simulation system is developed, which has many functions, such as inputting boundary conditions, earthwork balance calculation and transportation simulation, filling process simulation, result analysis, 3D demonstration etc. It provides a high efficient platform to discuss the rationality of construction plans, multi-plans comparison and sensitivity analysis, and also increases the precision and optimization degree of construction management plans.