Accession Number : AD0692300

Title :   EFFECTS OF AXIAL RESTRAINT ON LENGTH CHANGE OF EXPANDING MORTAR BARS.

Descriptive Note : Final rept. 1959-68,

Corporate Author : ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MISS

Personal Author(s) : Houston,Billy J.

Report Date : JUL 1969

Pagination or Media Count : 48

Abstract : An investigation was conducted to determine the effects of axial restraint on length change of mortar prisms tending to expand due to alkali-silica reaction. Three approaches were taken. The first involved use of external restraint on expansive mortar prisms. Restraining rigs consisted of aluminum rods held in place by steel header plates and load cells for determining stress caused by expansion. The next approach involved use of polyester laminated strain gages embedded axially in expansive prisms for determining stress. Restraint was provided by external frames. The third approach involved use of axially embedded calibrated steel restraining rods with end plates screwed on the ends of each rod. Linear expansion was reduced 80, 90, and 94% by the three restraints. Tests of cubes sawed from the prism after 1-yr exposure indicated that restraint had little or no effect on compressive strength. (Author)

Descriptors :   (*CONCRETE, RODS), (*ELONGATION, REDUCTION), CEMENTS, STRESSES, LOADS(FORCES), TEST METHODS, TEST EQUIPMENT, SILICON DIOXIDE, STRAIN GAGES, PRISMATIC BODIES, MEASUREMENT, DEGRADATION, COMPRESSIVE PROPERTIES, MOLDINGS, CREEP, APPROXIMATION(MATHEMATICS), EXPERIMENTAL DATA, ACCURACY

Subject Categories : Ceramics, Refractories and Glass
      Construction Equipment, Materials & Supplies
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE