The Comprehensive Error Analysis Of The Concrete Beam Experiment

Any result of a measurement is containing not only the value of the measurement but also the value or extent of the measurement value's error because of no measurement result without error. People always evaluate the quality of the measurement result by classical error theory and error analysis. In fact, the error of the measurement result (the difference between the true value and the result of measurement) is unknown. So with the transition from classical error theory to modern error theory, people gradually accept that the reliability standard of the result of measurement is expressed by measurement uncertainty. If we study the error's regularities of distribution and synthetic method, and correctly evaluate the measurement uncertainty, we can know how to correctly choose testing instrument, optimize the measurement process, reduce the testing cost, increase the reliability of the measurement result, and use effectively the testing data for project.The theory of measurement uncertainty in construction experiment has to be deepened, and problems in the application have to be resolved. A set of tests are performed in this paper to deal with the flexural RC beams. And how to plan measurement process through rational measuring principle is discussed in this paper. Critical dimensions are measured directly and the controlling factors of damaged beam are measured indirectly through establishing mathematical model, which are the deflection and moment at the middle of the span. All errors which are influencing the measurement result are analyzed and assessed in the whole measuring process, which including indication error of all instruments used in the experiment (steel measuring tape, dial indicator, displacement sensor, hydraulic compression-testing machine). The mathematical models measuring the deflection and moment conclude many values, which are analyzed and assessed by the theory of measurement uncertainty. Then all components are combined on the basis of the Law of propagation of uncertainty, and calculating the overall degrees of freedom. Finally, they are generalized the uncertainty report.