| For the vertical reinforcement connection mode of prefabricated shear wall structure system,the restrained lap connection proposed by the research group of Harbin University of Technology has been proved to have good lap performance by test and practical engineering.At the same time,at the present stage,there are no relevant specifications for inspection and inspection of vertical connections for quality problems of assembly construction,which restricts the popularization of assembly structures;moreover,combined with integral shear force,the performance of constrained overlap connections under the specification requirements of overlap length l_l=l_a needs to be improved.In this paper,the fabrication and construction method of prefabricated partially overlapped slab shear wall is proposed for the first time,and the mechanism of restrained overlapped connection and the related research of inspection and detection are carried out.Specific research contents are as follows:In order to improve the performance of restrained overlap connection when the overlap length l_l=l_a and to explore the solution when grouting construction does not meet the design requirements,18 restrained grouting anchor overlap connection specimens and 36 restrained concrete anchor lap connection specimens with different stirrup ratio,different grouting saturation/concrete compactness,different concrete strength have been completed based on the overlap length l_l=l_a.Experiments show that increasing the stirrup ratio can improve the effect of grouting insufficiency/concrete non-compactness on the overlap performance of reinforcing bars to a certain extent.Based on the test results and overlap mechanism model,the limit value of spiral stirrup ring diameter when overlap length l_l=l_a and the calculation formula of volume ratio of spiral stirrups with different diameters are deduced and simplified,and the corresponding tables of reinforcement suggestions are given.In order to fill in the vacancy of relevant standards for inspection and inspection of overlap connection of assembled confined grouting anchor,three specimens with different fullness were tested along grouting channels at different ages before and after grouting by ultrasonic method.It was found that the sound velocity after grouting was significantly higher than that before grouting,and the difference of sound velocity increased with the increase of grouting age.It shows that the ultrasonic velocity can truly and effectively reflect the grouting plumpness of the specimens.On this basis,the calculation model of the ultrasonic propagation path is established,and the calculated value is compared with the experimental value.The sound velocity ratio is introduced as a criterion to determine the saturation of grouting for overlap connection of confined grouting anchor.Sample selection and location are determined,and detection steps,criteria for judging plumpness and record tables are given.In order to improve the efficiency of component fabrication and installation,combined with the advantages of integral shear wall and composite shear wall,the method of fabrication and construction of prefabricated partially composite slab shear wall is put forward for the first time by adopting the idea of overlapping zone and integral prefabrication.In order to further verify its connection and seismic performance,the fabrication,installation and pseudo-static test of three prefabricated partially laminated shear wall specimens were carried out,and compared with three prefabricated laminated shear wall specimens and three common cast-in-situ shear wall specimens completed by the research group.The results show that the precast partially laminated slab shear wall with restrained concrete anchor overlap connection has reliable overlap of vertical reinforcement,full hysteretic curve and no obvious rigidity degradation,high ductility coefficient,and the test results are similar to those of precast laminated slab shear wall specimens.Compared with cast-in-situ shear wall specimens,the shear wall specimens have lower bearing capacity,better ductility and energy dissipation capacity,which meet the requirements of seismic performance. |
