| In this paper,two new connection nodes of ALC exterior wall panels connected to assembled steel frames are designed to simulate the action of seismic transverse waves by horizontal low circumferential reciprocal loads,and to compare the seismic performance with the hook-and-bolt connections of conventional exterior wall panels.The durability test of the anchor bolts connecting the ALC wall panel to the insulation and decoration integrated panel in the actual environment of high temperature and humidity was also studied to investigate the service life of the anchor bolts under this working condition.Specifically,in this paper,two types of cross-shaped connectors and combined rocker connectors are designed for the footprint seismic testing of steel frame-filled ALC wall panels,respectively,and hook-and-bolt connectors are used as conventional ALC wall panels for comparison with steel frame connectors.The effects of different types of wall panel connectors on the seismic performance of the overall frame were analyzed and studied in detail.The details of the work and the conclusions are as follows.（1）The effective connection between ALC wall panels and steel frames is studied.Two new connection nodes are proposed in this study.The test proves that the specimens using the new nodes have less structural damage and can accommodate larger inter-story deformation,avoiding unnecessary losses due to repairing wall panels when minor disasters occur.The hysteresis loop envelope area of the specimens with the new nodes is more rounded and full,and the bearing capacity is increased by 10% and the damage displacement is increased by 20%,which can improve the stiffness and bearing capacity of the ALC slab-frame synergistic system.The new connection node can ensure the normal operation of the structure under low circumferential reciprocating load,which is beneficial to the seismic resistance of the structure and has a high value of promotion and use.（2）The hysteresis curves of all three types of ALC connector frames were inverse S-shaped.Under the same level of late displacement,the load capacity of both the cross-shaped connector group and the combined swing connector group was greater than that of the hook head bolt group.More importantly,under the same horizontal load,the specimen hook head bolts exhibited more brittle phenomena,stiffness degradation,and strength degradation than the specimen cross-shaped connectors and combined swing connectors.The cross-shaped connectors and combined swing connectors were in a swing dissipation state before the initial stage of the test and provided higher stiffness and load carrying capacity for the frame in the later stage due to the restricted bolt hole slip displacement.（3）The skeleton curve of the hook head bolts was steeper than that of the cross-shaped joint and the combined swing joint at the beginning of loading,indicating that the stiffness of the steel frame external wall panel system with hook head bolts degraded faster at the beginning of loading,and with the increase of displacement,all three curves gradually became flat,and the hook head bolts and the cross-shaped joint reached the peak load and peak displacement almost simultaneously.The load carrying capacity of the hook head bolt system is reduced by 13.25 k N compared with that of the cross-shaped joint.at this time,the combined swing joint has a slow rise period before reaching the peak load and the load carrying capacity is larger because the wall plate has better follower performance,which delays the damage of the joint and the wall plate.In addition also through field research found a glue-injected ALC wall panel and insulation decorative integrated panel anchor bolt connection,consider the glue will be in the high temperature and humid heat and rain environment bearing capacity failure,so the durability test was carried out,the anchor bolt bearing capacity failure law,while contacting the actual weather conditions,can be analyzed under this connection,the anchor bolt detection,reinforcement and replacement years,to ensure the safety of the structure.The details of the work and the conclusions are as follows.（1）During vertical tension loading,the damage to the bolt is actually the damage to the anchor adhesive,and during the pull-out process,the bolt is completely pulled out and damaged.The degree of bolt damage was related to the number of hot rain cycles.The anchor bolts in the uncycled test group were the most severely damaged.The form of compression and tension on the surface of the expansion tube is related to the number of cycles,the more cycles the coefficient,the lighter the damage form,the closer to the damage form without glue injection.Combined with the analysis of the maximum bearing capacity,it can be seen that as the number of cycles increases,the smaller the tensile bearing capacity carried by the anchor bolt,the smaller the tensile force jointly borne by the glue and the anchor bolt,so the damage is lighter.（2）With the increase of the number of high temperature and humidity cycles,the anchor bolt tensile bearing capacity value gradually decreases,and the anchor bolt bearing capacity folding and deceleration rate gradually decreases with the data of non-cycling group as the base data.Compared with the traditional anchor bolt anchoring method,adding anchor adhesive can increase the anchor bearing capacity of ALC board and exterior insulation decorative integrated board by 234%.It can meet the requirements of high-rise assembly building on the anchorage performance of external insulation decorative integrated board.（3）The load-displacement curve can be divided into two stages.In the rising stage,the anchoring adhesive plays a controlling role until the ultimate load is reached.Before reaching the maximum load,the load-displacement curve shows an upward trend.After the maximum load is reached,the curve decreases.The anchorage adhesive has started to lose most of its force（failure）,while the mechanical bite and friction forces are only a small part,so the load drops faster.At the late stage of loading,the adhesive bond has been lost due to huge slip,and the load-bearing capacity of anchor rods mainly relies on mechanical bite and friction.（4）The bond shear strength of the colloid is calculated using the uniform bond stress model.The load-bearing capacity discount factor is calculated after cyclic loading.With the increase of the number of cycles,the bond strength decreases nonlinearly,and the rate of decline gradually slows down.The bond strength scatter diagram was plotted and a nonlinear fit was performed.The fitted correlation coefficients were all close to 1,indicating that the overall fitting effect was good.（5）Climate data from three urban areas were used as an example.The service life of anchor bolts was calculated in combination with the fitting formula for the number of cycles of bond strength for testing,reinforcement and replacement.Therefore,the safety and reliability of ALC and exterior insulation decorative integrated panels can be ensured.Figure [57] table [9] reference [61]... |
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