Accession Number : AD0647006

Title :   A STUDY OF THE RESPONSE OF BACKPACKING MATERIAL ENCASING A TUNNEL LINER SUBJECTED TO A DYNAMIC DISTURBANCE,

Corporate Author : TEXAS UNIV AUSTIN STRUCTURAL MECHANICS LAB

Personal Author(s) : Nosseir,Salah ; Perry,Ervin S. ; Thompson,J. Neils

Report Date : DEC 1966

Pagination or Media Count : 67

Abstract : Deformation behavior is presented for a crushable backpacking material (flat-top stress-strain behavior) encasing a cylindrical tunnel liner, when the surrounding media is subjected to a dynamic disturbance. A mathematical model consisting of a two-degree-of-freedom lumped mass system which approximates the behavior of a tunnel liner backpacking system is used for the analysis. The resistance of the backpacking material is represented by bilinear springs. The differential equations used in representing the motions of the system are presented. An analog computer was used to determine the response of the system. Design-aid curves are presented to help a designer choose the most desirable parameters for the backpacking material for certain design conditions. The main variables in the study were: (a) crushing strength of the backpacking material, (b) mass of the liner, (c) amplitude of disturbing displacement function, and (d) duration of the disturbing displacement function. (Author)

Descriptors :   (*UNDERGROUND STRUCTURES, CONSTRUCTION MATERIALS), (*CONSTRUCTION MATERIALS, DEFORMATION), MATHEMATICAL MODELS, DIFFERENTIAL EQUATIONS, EQUATIONS OF MOTION, LOADS(FORCES), SHOCK WAVES, NUCLEAR EXPLOSION DAMAGE

Subject Categories : Construction Equipment, Materials & Supplies
      Structural Engineering and Building Technology

Distribution Statement : APPROVED FOR PUBLIC RELEASE