Concrete in reinforced concrete structure (RC) is generally under significant compressive stress load. To guarantee required quality and ductility, various tests have to be conducted to measure the concrete’s compres...Concrete in reinforced concrete structure (RC) is generally under significant compressive stress load. To guarantee required quality and ductility, various tests have to be conducted to measure the concrete’s compressive strength based on ACI (American Concrete Institute) code. Investigations of recent devastating collapses of structures around the world showed that some of the collapses directly resulted from the poor quality of the concrete. The lesson learned from these tragedies is that guaranteeing high quality of concrete is one of the most important factors ensuring the safety of the reinforced concrete structure. In order to ensure high quality of concrete, a new method for analyzing and evaluating the concrete production process is called for. In this paper, the indices of fit and stable degree are proposed as basis to evaluate the fitness and stability of concrete’s compressive strength. These two indices are combined to define and evaluate the quality index of the compressive strength of concrete. Prin-ciples of statistics are used to derive the best estimators of these indices. Based on the outcome of the study, a concrete compres-sive strength quality control chart is proposed as a tool to help the evaluation process. Finally, a new evaluation procedure to assess the quality control capability of the individual concrete manufacturer is also proposed.展开更多
[Objectives]To establish a quality control chart of DHA in milk powder and determine whether the detection process and results are in control state.[Methods]The content of DHA in milk powder control samples was determ...[Objectives]To establish a quality control chart of DHA in milk powder and determine whether the detection process and results are in control state.[Methods]The content of DHA in milk powder control samples was determined by gas chromatography,and the quality control chart of DHA was established to analyze the controlled state.[Results]the median of the quality control chart was 23.85 mg/100 g,and the standard deviation was 1.00 mg/100 g.In the evaluation and analysis of the new quality control points,it can be seen that the point beyond the warning limit was 1,and the outlier value was not beyond the action line,and the mean value did not change,indicating that the detection is in the statistical control state,and the detection process,method and results are controlled.[Conclusions]The establishment and review of the control chart in this study are expected to provide a reference for other subsequent quality controls.展开更多
基金Project (No. NSC92-2213-e-167-001) supported by the National Science Council, Taiwan, China
文摘Concrete in reinforced concrete structure (RC) is generally under significant compressive stress load. To guarantee required quality and ductility, various tests have to be conducted to measure the concrete’s compressive strength based on ACI (American Concrete Institute) code. Investigations of recent devastating collapses of structures around the world showed that some of the collapses directly resulted from the poor quality of the concrete. The lesson learned from these tragedies is that guaranteeing high quality of concrete is one of the most important factors ensuring the safety of the reinforced concrete structure. In order to ensure high quality of concrete, a new method for analyzing and evaluating the concrete production process is called for. In this paper, the indices of fit and stable degree are proposed as basis to evaluate the fitness and stability of concrete’s compressive strength. These two indices are combined to define and evaluate the quality index of the compressive strength of concrete. Prin-ciples of statistics are used to derive the best estimators of these indices. Based on the outcome of the study, a concrete compres-sive strength quality control chart is proposed as a tool to help the evaluation process. Finally, a new evaluation procedure to assess the quality control capability of the individual concrete manufacturer is also proposed.
基金Supported by The Inner Mongolia Autonomous Region's Key Research and Achievement Transformation Plan(2023YFHH0093).
文摘[Objectives]To establish a quality control chart of DHA in milk powder and determine whether the detection process and results are in control state.[Methods]The content of DHA in milk powder control samples was determined by gas chromatography,and the quality control chart of DHA was established to analyze the controlled state.[Results]the median of the quality control chart was 23.85 mg/100 g,and the standard deviation was 1.00 mg/100 g.In the evaluation and analysis of the new quality control points,it can be seen that the point beyond the warning limit was 1,and the outlier value was not beyond the action line,and the mean value did not change,indicating that the detection is in the statistical control state,and the detection process,method and results are controlled.[Conclusions]The establishment and review of the control chart in this study are expected to provide a reference for other subsequent quality controls.
