Study On Maintenance Technology Of Planar Steel Gate Based On Time-varying Reliability

Hydraulic steel gate is the basic facilities of the hydraulic structures and its safe operation will influence the safety of the whole hydroproject.So it is of great significance to study the operation state and the corresponding maintenance technology of the gate.At present,there is no mature calculation method for the reliable index of the system of hydraulic steel gate,the reliability index of the main beam system is relative rich as there are many researches on the single component.The beam system is simplified in this article based on the girder,the secondary beam and vertical beam of the gate are distributed to the main girder of the gate in the form of equal quality.The reliable index of each main beam system is calculated,and the single component reliable index calculation method of JC and MC are validated and compared respectively via Matlab based on plane steel gate girder system reliability analysis during the study.It is verified that the result of JC is more accurate than MC,and the reliable index is calculated by PNET based on the above,finding that it is more realistic to calculate the corrosion rate as the variable reliability index after the calculation and comparison of the linear and nonlinear model with the combination of project cases.The time-varying reliability index of the plane gate of Fengman overflow dam and its value is 4.3567.According to the design specification of the existing steel gate(SL74— 2013),and the reconditioned and maintenance techniques are formulated with the fully consideration of safety reserve of the gate,suggesting that The proposed time period of the general and structural overhaul is both 10 years and the details and the specific contents of general and structural overhaul are put forward.