Research On Stress Strain Monitoring Data Analysis Of Concrete Dam And System Development

With the high-speed development of hydropower exploitation and construction, China leads the world in under construction and design of concrete dam, whatever it's number and height. The huge scale of project bring numerous technical problems, and we all face unprecedented challenges, therefor, safety monitoring especially stress and strain monitoring highlight the significance.Stress and strain monitoring is the important measures to grasp the running state of the structure, to ensure the use of dam safety, it's also the effective measures to supervise construction quality, get feedback of design results, and understand the variation of various physical quantities of dam; it's data analysis is the most cumbersome and complex one, which include the material properties of concrete stress-strain and free volume deformation, data error detection and correction technology, instrument analysis and textual research, etc.This paper aims to establish an efficient process flow and analysis model for the stress and strain monitoring data analysis of concrete dam, and develop the common software system, the main work includes:(1) Research the material properties of concrete stress-strain and free volume deformation, derivate and inducte the core formula which related to stress and strain analysis of monitoring data, focuses on optimizing the concrete creep ctress calculation method.(2) Pre-treatment of observation data:for the instrument characteristics of strain gauge set, establish a complete process flow, which contains selection of the reference value, data error detection and correction and compensation calculation of damaged instrument, etc. Above can effectively exclude abnormal values interference and improve the accuracy of observational data analysis.(3) No-stress meter data analysis:inversion of linear expansion coefficient of concrete and get the observed autogenous volume deformation, analyzed by statistical regression model. Which used to calculate stress strain coordinating with strain gauge set, and learn the actual work behavior of concrete, so that to determine the reliability of the observation data.(4) Strain gauge set calculation and analysis:contrast and discuss the various forms of structure, and derive the corresponding formulas, establish common concrete stress calculation model. The outcome include positive/shear stress, principal stress and directions, the maximum shear stress, etc. We can proceed qualitative analysis and quantitative analysis of stress statistical model.Based on the above, unified design and implement the processing and analysis of stress and strain of monitoring data of concrete dam, finally developed the API: com.crsri.stress.jar and common database templates Stress.sql, which could integrate professional and efficient analysis module of stress strain data for safety monitoring information system.