Abstract:
VARIOUS RESEARCH PROJECTS, OBJECTIVES AND CONCLUSIONS ARE DESCRIBED. REINFORCED CONCRETE WALL AND COLUMN FOOTINGS TESTS WERE INITIATED IN 1944 AND FINISHED IN 1948 AT THE UNIVERSITY OF ILLINOIS. TWO INVESTIGATIONS OF THE COMPARATIVE BONDING EFFICIENCIES OF MORE THAN TWENTY DIFFERENT DESIGNS OF REINFORCING BARS HAVE BEEN CONDUCTED AT THE NATIONAL BUREAU OF STANDARDS. THREE SIZES OF BAR HAVE BEEN TESTED IN BOTH BEAM AND PULL-OUT SPECIMENS WITH THREE STRENGTHS OF CONCRETE. BARS WERE PLACED IN BOTH BOTTOM AND TOP POSITION AND SLIP VALUES WERE MEASURED AT BOTH LOADED AND FREE ENDS. THE DATA HAVE NOT YET BEEN ASSEMBLED BUT A REPORT SHOULD BE AVAILABLE IN PUBLISHED FORM IN THE NEAR FUTURE. THE LONGITUDINAL DISTRIBUTION OF BOND STRESS IN REINFORCED CONCRETE MEMBERS WAS STUDIED AT CORNELL UNIVERSITY IN 1964 A NEW AND UNUSUAL TECHNIQUES HAS BEEN EMPLOYED IN WHICH THE REINFORCING BAR IS SPLIT LENGTHWISE, A SMALL GROOVE IS CUT ON THE INTERIOR OF THE BAR TO PERMIT THE PLACEMENT OF SR4 STRAIN GAGES AND THEIR CONNECTIONS ON THE INSIDE. THREE NEW PROJECTS STARTED IN 1948 ARE AS FOLLOWS: AT THE NATIONAL BUREAU OF STANDARDS, IN A SERIES OF TESTS ON SHEAR OR DIAGONAL TENSION IN BEAMS, THE ACTUAL STRESSES WERE MEASURED IN CONVENTIONAL VERTICAL STIRRUPS BY MEANS OF SR4 STRAIN GAGES. AT IOWA STATE COLLEGE THE SPACING OF BARS IN JOISTS AND BEAMS, INCLUDING THE RELATION TO LAPPED SPLICES WERE INVESTIGATED. AT THE UNIVERSITY OF WISCONSIN THE LONG- TIME PLASTIC FLOW WAS STUDIED OF LONG SPAN, SHALLOW SLABS AND BEAMS USING TENSILE STEEL ONLY IN CERTAIN MEMBERS AND BOTH TENSILE AND COMPRESSIVE STEEL IN OTHERS. /AUTHOR/
Supplemental Notes:
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