OPTIMUM DESIGN OF UNBRACED MULTI-STORY FRAMES BY PLASTIC THEORY.
Abstract
A computer program is described which performs weight optimization of three-bay multi-story frames using plastic theory. The input consists of the frame geometry and the load intensity. The maximum number of stories depends only on the computer storage capacity. Three loading cases with corresponding load factors are considered: vertical loads only, vertical loads combined with lateral loads from the left, and vertical loads combined with lateral loads from the right. Loads are modified to include pertinent load reduction criteria. Where combined loads govern the size of members, the ratio of the capacities of individual members is determined by an iterative procedure using frame weight as the minimized function. Provision is made for consideration of second-order effects. The output of the program consists of the member forces needed for design of connections, and of member sizes. Refinement of the member sizes to account for frame instability and constructional details should be performed to complete the design. Weight comparisons for a frame designed for allowable stresses and plastic theory without optimization are presented. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1966
- Accession Number
- AD0638226
Entities
People
- Alexis Ostapenko
- Thomas M. Murray