ISSN: 0149-6123
CODEN: CCAGPD
Page Count: 5

A Strain Control System for Relaxation Studies of Concrete
Pirtz, D
Professor of civil engineering and visiting Fulbright senior scholar, University of California, CA

Thomas, K
Professor of civil engineering and visiting Fulbright senior scholar, University of California, CA

Abstract

This paper describes a system of automatic strain control devised to maintain constant strain in concrete specimens during stress relaxation tests. The system also makes provision for continuous monitoring of strain and stress as the testing proceeds. Evaluation of the system performance from the results of relaxation tests conducted using the system showed that the strain control achieved during these tests was remarkably effective. The maximum variation from initial strain recorded was 0.5 × 10⁻⁶ microstrain (0.5 × 10⁻⁶ in./in.)

Keywords:
concretes, stress relaxation, strains, pressure, strain control, imbalance, bridge circuits, hydraulic control

Paper ID: CCA10223J
DOI: 10.1520/CCA10223J
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