Study On Vibration Comfort Of Hydraulic Structure Based On Ansnoyance Rate Model

In the past less than one hundred years,the hydraulic engineering construction has developed rapidly in China and the quantity and technology of those high-head hydraulic structures are in the world's leading position.At the same time,the high-energy impact and pulsation caused by high-speed water flow can cause strong vibrations in the hydraulic structure.It may not only adversely affect the safety of the structure or even damage the structure itself,but may also affect the comfort and operation of the workers on the hydraulic structure,and indirectly affect the operational safety of the hydraulic structure.At the same time,the high-energy impact and pulsation caused by high-speed water flow can cause strong vibrations in the hydraulic structure.It may not only have an adverse affect on the safety of the structure or even damage the structure itself,but may also lead to have a bad effect on the comfort and operation of the workers and the operational safety of the hydraulic structure.In the evaluation of structural safety and human comfort,parameters such as displacement,velocity and acceleration are often used as evaluation indicators.Due to the limitations of hydraulic structures in prototype observation,the prototype observation is difficult even impossible in the underwater or corridors,and these locations may be the key points of evaluation.In addition,some hydraulic structures are mainly horizontal vibrations excited by flood discharges.But the existing evaluation methods and standards are generally aim at the vertical vibration rather than the horizontal vibration.It causes the lack of the evaluation methods and standards for the comfort evaluation of hydraulic structures,and the existing evaluation can only be qualitative but can be not quantitative to analyze the subjective feelings of the human body on vibration,so there is an urgent need for a solution to such problems.To sum up,it is of great significance to use the finite point response to obtain the response of any part of the whole structure and quantitatively assess the subjective feelings of people in the hydraulic structure.In this paper,based on the back analysis theory of discharge structure and the annoyance rate model,the human vibration comfort is evaluated.The following work is as follows:(1)List and summarize the existing standards and methods of the domestic and international building vibration comfort evaluation,specify the vibration measurement,frequency weighting,evaluation methods,evaluation indicators and limits,and supplement the absorption power method and wavelet packet.The principle of the transformation method is summarized in the evaluation indicators and applicability of the above-listed standards,and the similarities and differences are analyzed.(2)The dynamic displacement back analysis of the Ertan arch dam and the left and right piers of the 2# gate of the Shuhe flood sluice are carried out.Taking the dynamic displacement time history data under three working conditions as the known condition,the frequency composition of the structure is obtained by time-frequency analysis,then the finite element model of the two structures is established and the structural property information is extracted.Based on the forward and reverse analysis and the optimization of genetic algorithm,the displacement field of the structure is obtained and compared with the known measurement data to prove the accuracy of the back analysis results.The dynamic displacement data obtained by the inverse analysis of any node of the structure will be used at the evaluation of the comfort of the two structures by the annoyance rate model later.(3)The comfort evaluations of the Ertan arch dam and the left and right piers of the 2# gate of the Shuhe flood sluice are carried out based on the annoyance rate model.Transforming the back analysis data of the displacement response into the weighted acceleration data,using the annoyance rate curve under different boundary requirements,combining the weighted acceleration r.m.s value to calculate the annoyance rate of the two structural structures,and plotting the overall annoyance rate value of the structure to judge whether the vibration comfort can meet the comfort requirements of the human body.