SPLICED CONNECTIONS FOR ADJACENT PRECAST MEMBER BRIDGES USING ULTRA AND VERY HIGH PERFORMANCE CONCRETE

摘要

Spliced connections in the longitudinal joints of bridges with adjacent precast members are investigated as an alternative to the current grouted shear key connection. The minimum splice lengths are determined for No. 4 and No. 6 bars using fiber reinforced ultra and very high performance concretes (UHPC and VHPC) as connection materials. The minimum splice length is determined experimentally using simply supported reinforced concrete beam specimens with tension splices formed within a pocket filled with the fiber reinforced connection material. The test results are verified using a strain compatibility analysis of the beam specimens to confirm the yielding of tension steel. The experimental and analytical results show that the minimum splice length with No. 4 bars is 4 in. and that with No. 6 bars is 6 in. The conclusions made in this research show that UHPC and VHPC can be used to reduce the length of tension splices and these connections can be applied in longitudinal joints of adjacent precast member bridges.