Civil Engineering ETDs

Publication Date

5-20-1970

Abstract

A 9 inch in diameter rigid hemispherical dome was buried in the bottomless soil bins of a vertical shock tube. The interior diameter of the soil bins was 22-3/4 inches, with the interior wall being covered with a friction reducing membrane. An airblast was generated so as to strike the soil perpendicular to the soil surface. The peak reflected pressure of this airblast averaged 315 psi throughout the fourteen tests with the dome. Instrumentation measured the air pressures at the soil surface, the free-field soil stress above and below the dome, the radial on-structure stress on the dome, the rigid body velocity and acceleration of the dome, and the total vertical load on the dome. A full depth-of-burial of approximately 4 inches was found. A normalized radial peak dynamic pressure distribution was generated. The peak acceleration of the dome was measured to be between 2000 g and 3000 g. The peak dome velocity measured averaged approximately 60 inches per second. The mean peak total vertical load transmitted to the dome was approximately 22,000 pounds. There was very little passive arching found for loading to the peak load, with an arching factor of 1.02. Upon unloading the passive arching became much larger, with an arching factor of 1.38. This was caused by locking-in of soil stress. It was found that approximately 20 percent of the total load transmitted to the dome was obtained from shear stress loading on the surface of the dome. The results obtained for the peak radial on-structure stress, passive arching, and free-field stress were found to be similar to those reported for the static case, where a dome structure similar to the one used in this study was used.

Sponsors

United States Air Force (USAF)

Document Type

Thesis

Language

English

Degree Name

Civil Engineering

Level of Degree

Masters

Department Name

Civil Engineering

First Committee Member (Chair)

Marion Marvin Cottrell

Second Committee Member

R. B. McPherson

Third Committee Member

Howard Linn Schreyer

Fourth Committee Member

James Tsu-Ping Yao

Download

Share

COinS