FORMATION OF LONGITUDINAL CRACKS IN PRESTRESSED MEMBERS

UNTERSUCHUNGSVORHABEN "LAENGSRISSBILDUNG BEI SPANNGLIEDERN"

THE OBJECT OF THE RESEARCH IS TO CHECK THE CURRENTLY VALID MINIMUM REQUIREMENTS FOR CONCRETE COVER AND THE DISTANCE BETWEEN PRESTRESSED MEMBERS AND IF NECESSARY TO WORK OUT RECOMMENDATIONS FOR ESTABLISHING THESE IN SUCH A WAY AS TO AVOID LONGITUDINAL CRACK FORMATION AND TO GUARANTEE SUFFICIENT STRENGTH UP TO FAILURE, EVEN WHEN PARTIAL PRESTRESSING AND LARGE PRESTRESSED MEMBERS ARE USED. THE PROJECT CONSISTS OF THE FOLLOWING: EXECUTION OF 9 UNIAXIAL TENSILE TESTS FOR STUDYING THE LONGITUDINAL CRACK FORMATION; THEORETICAL CHECKING OF THE RESULTS OBTAINED FROM THE TESTS; WORKING OUT OF RECOMMENDATIONS FOR ESTABLISHING CONCRETE COVER AND SPACES BETWEEN PRESTRESSING MEMBERS TAKING ACCOUNT OF EXISTING TRANSVERSE REINFORCEMENT.