Study On Lapping Connection Performance Of Constrain-anchorage Reinforcement In Precast PC Components

Compared to the traditional Concrete structure,the precast concrete structure has the advantage of shorter construction period,higher construction accuracy,and lower construction cost in the long run,Based on these excellent characteristics,the precast concrete structure has become the important guiding of the development trend of construction industry as the important form of construction industrializationand housing industrialization.Theconnection and transmission performance of the steel bar determines the whole bearing capacity of the whole assembled concrete structure to a great extent.Under this situation,the experimental study on constraint grout-filled lap connection of precast concretecomponents is carried out in this paper.The study in this paper mainly focuses onconstraint grout-filled lap connection of precast concretecomponentsIn this paper,to be affecting parameters,the bardiameter,lapping length,the strength of concrete,arrangement of spiral reinforcement were checked to be analyzing.A total of 39 specimens were designed,According to the?Technical specification for mechanical splicing of steel reinforcing bars?(JGJ 107-2010),three kinds of experiments including single tensile test,repeated high pressure tensile and compression test and repeated large deformation tensile and compression test were designed respectively.andthe specific research contents include the following:(1)Research methods of control variables was used to analysis the load-displacement curve of simple tension test with different affecting parameters,The main conclusion as follow:?When the longitudinal reinforcement of Precast concrete member was used the constraint-anchorage connection,the lap length can not be shorter than 0.71aE.?When the longitudinal reinforcement of Precast concrete member was used the constraint-anchorage connection,the performance of constraint anchorage could be improved effectively with higher strength of concrete.?The double spiral reinforcement constrain-anchorage can also be used on lapping connection of longitudinal reinforcement of Precast concrete member.(2)By means of contrast and investigate theload-displacement curve of constraint anchorage specimen and Sleeve grouting test pieceunder three different kinds of loading system,the results indicate thatsleeve grouting connection form of longitudinal connecting bars connecting transmission performance is superior to restraint grouting anchoring connection form.(3)According to the evaluation methodology of performance grade of reinforcement joint from?Technical specification for mechanical splicing of steel reinforcing bars?,the two kinds of connection forms have good ductility characteristics and excellent performance under high stress repeated tension and compression,and the ability to withstand the large deformation and repeated compression and tension.