BRBF Designer Report

BRBF Designer Report Kelly Christensen Department of Civil and Environmental Engineering, BYU Master of Science Structural seismic analysis can be lengthy and complicated. Nonlinear analyses can be performed to accurately compute the response a structure has to an earthquake. A program called OpenSees is an excellent way to run a nonlinear analysis. Due to usability issues, a spreadsheet called BRBF Designer was created to assist users in running OpenSees. This spreadsheet was made to design a BRBF structure; any structure utilizing another lateral force resisting system cannot be designed in this spreadsheet. This spreadsheet greatly shortens the time one must spend when using OpenSees. When using this spreadsheet, one should proceed through the tabs, going from left to right. About the first half of the spreadsheet is used for designing the structure in question. This includes designing the geometry and number of stories, and inputting the loads and seismic parameters. When the design is complete the user will then run the nonlinear analysis in OpenSees using the text files that the spreadsheet creates. The OpenSees results must then be imported into the spreadsheet. The rest of the spreadsheet is dedicated to analyzing the results from OpenSees. The results consist of drift and displacement tables, hysteretic plots, and column/brace axial force plots. Animation plots for story displacement and hysteretic plots are also included. Because some of the calculations that the spreadsheet performs are convoluted, a MathCAD design example is provided. A section is also included for how the spreadsheet functions with some of the more complicated features.