Seismic rehabilitation of column to pier cap accelerated bridge construction connections and acoustic emission monitoring assessment.

摘要

A repair technique for damaged precast reinforced concrete bridge column to pier cap joints constructed with grouted splice sleeve connections has been developed using plastic hinge relocation. Undamaged column to pier cap specimens constructed with grouted splice sleeve connections were tested to failure using quasi-static cyclic loads applied in the horizontal direction at the top of the column. The column's plastic hinge region was subsequently repaired using prefabricated carbon fiber-reinforced polymer shells, epoxy anchored headed mild steel bars, and nonshrink or expansive concrete to increase the moment of inertia at the column base and relocate the plastic hinge in the column to a region with minor damage. Follow up quasi-static cyclic tests of the repaired specimens were performed to verify the effectiveness of the repair technique. Analytical strut and tie models of both the original and repaired specimens were developed and verified using the test results.;In addition to destructive tests, acoustic emission monitoring of grouted splice sleeves, the original specimens, and the repaired specimens were performed to correlate acoustic emissions to damage. To obtain an appropriate damage assessment of grouted splice sleeve connections using acoustic emissions monitoring, the acoustic emission characteristics of two different grouted splice sleeve systems were obtained by performing tension tests of the sleeves to failure. The acoustic emission monitoring system was then implemented on the original and repaired specimens to demonstrate the effectiveness of relating acoustic emissions to damage.