ELASTIC-PLASTIC-SOFTENING ANALYSIS OF PLANE FRAMES
Plastic collapse theory is nowadays accepted as a basis for limit load designing of steel frame structures. For reinforced concrete structures, the limited rotational capacity of hinges at plastic moment has hindered the substitution of limit design based on plastic theory for the existing ultimate strength design method. A rigorous collapse load analysis requires a knowledge of the behaviour of plastic hinges up to advanced curvatures. Concrete sections characteristically soften, that is the bending moment capacity decreases with increasing curvature after the end of the plastic plateau. It is possible for some sections of a frame to soften before the ultimate collapse load is reached. In this report, a direct stiffness method incorporating softening is used to find collapse loads of frames in which softening occurs. An existing computer program is modified to serve the above purpose. The report is divided into three parts. The first part is a review of those aspects of flexural mechanics of reinforced concrete which provide the rationale and the input data for the computer program. The second part is a general description of program paws, derived from ularc, with the major modifications required to take softening into account. The third part demonstrates some applications of the programs. The computer program and sample input and output are included as appendices. (Author/TRRL)
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Corporate Authors:
Monash University
Department of Civil Engineering
Clayton, Victoria Australia 3800 -
Authors:
- Mendis, P A
- Darvall, P L
- Publication Date: 1984
Media Info
- Features: Figures; References; Tables;
- Pagination: 83 p.
Subject/Index Terms
- TRT Terms: Collapse; Computer programs; Flexure; Framed structures; Hinges; Mechanical elasticity; Plasticity; Reinforced concrete; Softening point; Steel structures; Stiffness; Ultimate load design
- Old TRIS Terms: Plane structures; Stiffness methods (Structural); Ultimate strength design
- ITRD Terms: 6471: Analysis (math); 5586: Deflection; 5912: Elasticity; 5520: Failure; 3322: Frame; 8634: Input data; 5567: Load; 5455: Mechanics; 5922: Plasticity; 4794: Reinforced concrete; 5272: Softening; 8645: Software; 5931: Stiffness
- Subject Areas: Bridges and other structures; Highways;
Filing Info
- Accession Number: 00389925
- Record Type: Publication
- Source Agency: ARRB
- Report/Paper Numbers: 5/1984 Monograph
- Files: ITRD, TRIS, ATRI
- Created Date: Nov 30 1984 12:00AM