NEHRP Clearinghouse
- Title
- Seismic Stability of Block Structures.
- File
- PB81158578.pdf
- Author(s)
- Furgerson, R. L.
- Source
- National Science Foundation, Washington, DC. Engineering and Applied Science., May 1980, 104 p.
- Identifying Number(s)
- UCSD/AMES/TR-80/002
- Abstract
- Numerical techniques are used to solve a prototype structural stability problem involving a rigid body shear-wall-floor slab configuration with Coulomb friction acting between the vertical and horizontal elements. Motion of the base is excited by a simulated seismic loading. The assemblage is considered to be kinetically stable if the floor slab in responding to excitation does not fall off its supporting shearwalls. Hazard from collapse due to kinetic instability is inversely proportional to the time the assemblage can withstand excitation before collapsing. Structures with degraded connections are modeled as assemblages of rigid substructures with only friction acting between them. Statistical analysis of data from experiments in concrete masonry members gives an asymptotic Coulomb law describing this friction which is included in the model equations of motion. Results show a well-defined relation between the maximum amplitude of excitation, natural frequency of the structure, and a numerically-valued hazard from kinetic instability. Graphical representation permits a designer to assess hazard from kinetic structural instability by inspection.
- Keywords
- Earthquake resistant structures; Mathematical models; Walls; Dynamic response; Buildings; Earthquake engineering; Concrete structures; Concrete slabs; Shear stress; Coulomb friction