Title:
Stress Relaxation Phenomena at Early Technological Phases of Gas-Concrete
Author(s):
Videvud A. Lapsa
Publication:
Materials Journal
Volume:
96
Issue:
4
Appears on pages(s):
436-439
Keywords:
cracking (fracturing); foaming agents; slurries; tensile stress
DOI:
10.14359/643
Date:
7/1/1999
Abstract:
This paper is an attempt to develop a rheological explanation of the mechanics of creating qualitative or nonqualitative (cracked or uncracked) porous structures in the process of hydrogen foaming of gas-concrete slurry. For this goal, the simplest rheological model of similar mortar-type slurries, the E. C. Bingham’s Model, was used. The foaming process, and consequently the process of technological deformation of gas-concrete slurry, was approximated by a simple exponential equation. By solving the Bingham’s Model equation in the previously-mentioned manner of deformation, and taking into account the decreasing horizontal section of the cell walls, the theoretical kinetics of increase and relaxation for the tensile stresses in the cell walls during the foaming process were estimated. A comparison of the model to experimentally measure stresses was carried out, and the coincidence, as well as some disagreements, were discussed. The causes on noncoincidence are suggested. For more exact stress calculation in the previously-mentioned foaming process, the conception must be more complicated. The presented work in the first approximation for this purpose.