Accession Number : AD0475498


Title :   DIGITAL CALCULATION OF AXISYMMETRIC ELASTIC-PLASTIC GROUND MOTIONS FROM NUCLEAR BURSTS.


Descriptive Note : Technical rept. Feb 63-Jan 65,


Corporate Author : ILLINOIS UNIV AT URBANA DEPT OF CIVIL ENGINEERING


Personal Author(s) : Ang, Alfredo H -S ; Rainer, Johann H


Report Date : Nov 1965


Pagination or Media Count : 212


Abstract : Numerical solutions are presented to axially symmetric wave propagation problems in elastic and elastic-perfectly plastic solids. Use is made of mathematically consistent lumped parameter models in cylindrical-polar and spherical-polar coordinates to obtain strain relationships and equations of motions; the latter are then integrated by a numerical technique. The material behavior is specified by Hooke's law in the elastic range, the Prandtl-Reuss stress-strain laws in the plastic range, and Hooke's law in rate form for unloading. Mises' yield criterion determines the point of yielding. Results are presented in graphic form for: (a) directly induced motions and stresses in an elastic-perfectly plastic half-space (two different yield levels are considered); (b) motions and stresses in an elastic half-space due to a moving surface pressure wave which simulates the air shock wave emanating from a nuclear burst; (c) wave propagation in an elastic layered medium. By means of the lumped parameter mathematical model wave propagation phenomena can be simulated in the elastic as well as the perfectly plastic range of material behavior. A finite rise time for input pressure is required since the method is of a central finite difference character. Listings of the computer program in FORTRAN II are presented. (Author)


Descriptors :   *ELASTIC PROPERTIES , *NUCLEAR EXPLOSIONS , *SOILS , *SURFACE BURST , PLASTIC PROPERTIES , NUMERICAL METHODS AND PROCEDURES , AXISYMMETRIC FLOW , SHOCK WAVES , EQUATIONS OF MOTION , DIGITAL COMPUTERS , BOUNDARY VALUE PROBLEMS , AIRBURST , SOLIDS


Subject Categories : Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE