Research On High Arch Dam Construction Simulation Optimization Based On Chaos-differential Evolution-support Vector Machine Theory

The high arch dam has become one of the main dam types of water conservancy and hydropower projects because of its good anti overloading capacity,adaptive adjustment ability and economy.The construction processes of high arch dam are influenced by many factors,such as topography and geological conditions,construction technology,pouring machinery and construction materials,so the construction duration is long and the amount of engineering is huge.The simulation of construction schedule provides theory and method for construction schedule control of high arch dam.However,the current researches of concrete-placement sequencing exist unreasonable decision and complex calculation;updating methods of construction simulation parameters are unable to effectively track the actual construction situation;the construction duration of high arch dam is not consistent with the planned time period.Therefore,how to shorten the construction period and balance construction strength according to the actual situation of construction optimization of arch dam block sorting principle;how to optimize updating process of construction simulation parameters to achieve a precise description of actual construction parameter evolution process;how to solve the problem of construction period and planning period is not consistent so as to realize the management of the construction schedule control.Above all is the focus problems of high arch dam construction simulation.In this paper,the above problems are deeply studied and analyzed,and obtained the following results:(1)In view of the problems that unreasonable decision-making and complicated calculation in the current high arch dam sequencing research,a method of ranking high arch dam based on interval analytic hierarchy process and relative advantage relation is proposed.The existing concrete-placement sequencing researches have the following defects: 1)Part of the studies did not consider the site construction situation and the realization of the subjective opinions of the on-site decision-makers;2)The rationality of decision matrix normalization and attribute weight calculation should be further studied in some decision methods;3)The calculations of some studies are too complex and difficult to implement.In view of these problems,this paper analyzes in detail the sequencing principle of high arch dam.And based on the original attribute value of dam,relies on the construction schedule simulation model of high arch dam,integrates the actual construction scheme,real-time simulation progress and decision-maker's preference,the decision making model of dam block sequencing for high arch dam is constructed.By the fuzziness of quantitatively subjective judgment,avoiding the adverse influence that the normalization of the attribute matrix may have on the rationality of the sorting method and comparing the relative superiority relations among the dam blocks,the dynamic evaluation system that can comprehensively consider the actual construction scheme on site and the real-time simulation progress,reflect the differences among dams and reduce the computational complexity is established so as to realize a more reasonable concrete-placement sequencing evaluation.(2)In view of the fact that current updating methods of construction simulation parameters cannot effectively track the actual situation in the field,the chaotic theory and support vector machine theory are combined to propose a realtime updating method for the construction simulation parameters of high arch dam based on DE-SVM.The traditional high arch dam construction simulation parameter values are mostly based on similar engineering experience or construction specifications.Due to the particularity of large engineering,the difference between different projects is obvious and it has low reference.Bayesian update methods can adaptively update the simulation model by using field information and prior information,so as to improve the accuracy of construction simulation results.However,the existing Bayesian updating methods assume that the values of construction simulation parameters are in normal distribution and the frequency of parameters update is low,so it is difficult to accurately describe the variation process of construction simulation parameters.In order to solve these problems,based on the time series of on-site construction parameters values,the chaos theory is introduced into the process of construction simulation parameters updating,the chaotic phase space reconstruction is used to map the time series of construction parameters into high dimensional sequences,the differential evolution support vector machine is used to solve the high dimensional sequences,and then the prediction is updated.The method can accurately describe the nonlinear change process of construction simulation parameters.Besides,its ability of strong generalization and real-time update make up the shortcomings of the traditional method and the Bayesian update method.The whole process simulation and the small-scale precision simulation realized the dynamic tracking of construction simulation parameters.(3)In view of the influence of construction parameters and parameter combinations on the sensitivity of construction duration,a comprehensive global sensitivity analysis method of construction parameters of high arch dam based on orthogonal experimental design is proposed.At present,the research on the sensitivity of construction period of high arch dam is mostly based on the single-parameter sensitivity analysis.The parameter selection does not consider the whole construction process.A small number of proposed sensitivity analysis frameworks for parameter combinations are not implemented and can not effectively analyze the construction duration sensitivity of high arch dam.And the guidance on the progress of construction control is limited.In response to these problems,based on the orthogonal test method,considering the construction parameters that affect the sensitivity of the construction period,this paper analyzes the global comprehensive sensitivity of the whole process of high arch dam construction.By calculating the main effect of construction parameters,the key parameters affecting the sensitivity of construction period are obtained,which provides scientific guidance for optimizing the construction parameters;then,based on the analysis of the main effects,the paper analyzes the interaction effects of the parameter combinations,summarizes the general rules of the interaction effects of the parameter combinations,identifies the interaction effects combinations that can reduce the mechanical adjustment complexity,and then combines with the key control parameters to make the combination of the construction parameters more rationalization,provide a reference for the high arch dam site construction schedule control.The above research methods and achievements are applied to practical projects.Practice shows that the research contents of this paper can effectively optimize the simulation process of high arch dam construction and provide scientific guidance for the construction schedule control of high arch dams.