Li Dianqing

Reliability Calibration of Hydraulic Gates for Serviceability Limit State

This paper aims to propose a procedure to calibrate the reliability level of hydraulic gates for serviceability limit state associated with the Chinese hydraulic gates design code SL 74 - 95. Firstly, the serviceability limit state function for main beams on hydraulic gates is established. Statistical parameters of variables underlying the serviceability limit state function are determined. Secondly, probabilistic load models for the serviceability limit state are developed. Reliability analysis for serviceability limit state is performed using the first-order reliability method. Finally, target reliability indexes are recommended for the design of main beams on hydraulic gates. The results indicate that the calculated reliability indexes of hydraulic gates depend on the type of hydraulic gates, the variations of loads, and load combinations. The safety level of hydraulic gates for serviceability limit state is acceptable based on the target reliability level recommended by ISO 2394. The proposed target reliability indexes for serviceability limit state is 2.0 for the design of the main beams on hydraulic gates. These results can form a basis for developing reliability based design procedure of hydraulic gates and for revising the Chinese hydraulic gates design code SL 74 - 95.

Reliability Analysis of Skin Plates on Hydraulic Gates

The objective of this paper is to propose a procedure to evaluate the reliability level of skin plates on hydraulic gates associated with the Chinese hydraulic gates design code SL 74–95. Firstly, the limit state function for reliability analysis of the skin plates is established. Secondly, probabilistic load and resistance models for the skin plates on hydraulic gates are developed. Furthermore, statistical parameters of load and resistance are determined. Finally, target reliability indexes are recommended for the design of skin plates on hydraulic gates. Examples are investigated to illustrate the proposed procedure. The results indicate that the calculated reliability indexes of the skin plates depend on the skin plate specifics, the type of hydraulic gates, the safety level of hydraulic gates and the materials used by skin plates. The proposed target reliability indexes are 4.7, 3.9, and 3.4 for the design of the skin plates on safety level I, II, and III crest gates, respectively. They are 4.4, 3.6, and 3.1 for the design of the skin plates on safety level I, II, and III submersible gates, respectively. These results can form a basis to develop load and resistance factors for reliability-based design of the skin plates on hydraulic gates.