Research On Computer-aided Design Of Prestressed Anchor Frame Beam

Prestressed anchor frame beam, which has lots of unique advantages, is one of the effective supporting means of strengthening high steep rock slope, but its heavy design and calculation process is rather complicated and time-consuming which brings a lot of inconvenience to the designers. Thus the calculation for the design of prestressed anchor frame beam was focused on in this paper. Firstly, calculation for internal force of frame beam was studied and several commonly used formulas of the beam on elastic foundation were derived through theoretical analysis; then combined with the load calculation on the supporting structure, the design process and methods of computation for prestressed anchor frame beam were summarized; finally based on Visual Basic6.0and the secondary development for AutoCAD on Visual Basic6.0, a computer-aided design system for slope supporting computing was developed, which has the functions to carry out landslide model identification, stability analysis and supporting structure design. The research results are as follows:(1)Based on theories for beams on elastic foundation, the scope of application and advantages and disadvantages of three kinds of elastic foundation model—Winkler foundation model; Variable coefficients of bedding foundation model and Two-parameter foundation model—were analyzed and compared respectively, meanwhile the formula for the calculation of internal force of frame beam was derived.(2)For different sliding models, the formula of landslide thrust was derived through the analysis of the load on the supporting structure, and then program interfaces for the calculation of varieties of landslide thrust and a program for the calculation of landslide thrust through transfer coefficient method were developed.(3)For the calculation and analysis of slope stability, a program which has the functions to search for the most unfavorable slip surface automatically and calculate its stability was developed for complex soil layers based on Sweden circle method. (4)The program for the structural design of prestressed anchor frame beam was completed in Visual Basic6.0. The program has the functions to carry out automatic modeling, interactive input of design parameters, landslide model identification, stability analysis, load calculation, calculation of anchor and frame, graphical display of the results, standardized design chart and output of design results. The accuracy and reliability that was verified by practical calculation proved the program to be a convenient, applicable and effective computer-aided design tool for prestressed anchor frame beam.