CREEP TESTS OF TWO-WAY PRESTRESSED CONCRETE

CREEP TESTS ON SMALL PRESTRESSED STRUCTURAL LIGHTWEIGHT CONCRETE SLABS ARE DISCUSSED. THREE 2 X 2 FT X 2-1/2 INCH SLABS PRESTRESSED EQUALLY IN TWO DIRECTIONS TO 1000, 2000, AND 3000 PSI, RESPECTIVELY, WERE GAGED FOR STRAIN. ONE SLAB OF SIMILAR DIMENSIONS WAS PRESTRESSED TO 2000 PSI IN ONE DIRECTION. SMALL 3 X 3 X 16 INCH PRISMS WERE SPRING LOADED AXIALLY TO THE SAME INITIAL STRESSES AS THE PRESTRESSED SLABS. IT WAS FOUND THAT CREEP IN THE 2000 PSI TWO-WAY SLAB WAS VIRTUALLY THE SAME AS THAT IN THE 2000 PSI ONE-WAY SLAB. PRESTRESS LOSSES AFTER 313 DAYS WERE ABOUT 25 AND 30 PERCENT IN THE 2000 AND 3000 PSI SLABS, RESPECTIVELY. /AUTHOR/