EXPERIMENT INVESTIGATION AND MECHANICAL BEHAVIOR ANALYSIS OF MULTIPLE CFRP TENDONS ANCHORAGE SYSTEM

In order to investigate the anchorage performance and internal stress distribution of multiple CFRP tendon bond-type anchorage, multiple CFRP tendon bond-type anchorage with 19 tendons was designed and static performance was tested. Three specimens were tested in which the space between CFRP tendons of the specimens were 4mm, 2mm and 1mm, respectively. The CFRP tendon strain in anchorage zone and the relative displacement of the anchorage barrel were recorded at each loading level. The anchorage performance, the bond tress distribution of CFRP tendon-mortar interface and the bond stress variation were investigated through static loading testing and theoretical analyzing. The results show that the anchorage efficiency coefficient of tested anchorage is 94.8%. The space between CFRP tendons makes great impact to the anchorage performance, the higher concentration of CFRP tendons the better anchorage performance. The rigid body displacement of mortar leads to the major relative displacement of CFRP tendon-anchorage barrel. The peak bond stress shifts from the load end to the free end of bond-type anchorage and increases gradually when the loading level increases. The surface compressive stress of CFRP tendon in anchorage zone is also a greater impact to the anchorage performance.