Optimum Cable Tension Adjustment Using Fuzzy Regression Analysis

To determine the optimum cable pre-stresses (i.e., prestress) in the design of cable-stayed bridges is one of the most important, but time consuming, procedures. Various kinds of errors will be introduced during construction. Therefore, cable length adjustment is necessary to alter the stress distribution and the geometrical configuration of the bridge. The authors have developed new methods to overcome these problems through the use of the fuzzy set theory. First, a method is formulated for obtaining optimum cable prestress. Secondly, a new system identification method is exploited by applying fuzzy regression analysis. Finally, a method is formulated to adjust the cable length by shim plates. The results of numerical examples show that the proposed methods are not only simple to handle, but also very practical for the design and construction of cable-stayed bridges.