Shaking Table Test Study On The Seismic Performance Of The Phenolic Board Thermal Insulation Finish Of The Outer Protective Wall Of The Frame Structure

Building energy efficiency is an important guarantee for the long-term stable development of my country’s construction industry,and its main approach is to achieve the external insulation system of the building’s external wall.The phenolic board exterior wall exterior insulation system has been widely used in new construction projects and energy-saving renovation projects of old communities because of its remarkable thermal insulation effect and high cost performance.However,in recent years,there have been accidents of high-altitude fall of the external thermal insulation system of the building’s exterior wall.Falling of the decorative layer from high altitude can cause casualties and seriously affect the safe operation of buildings.Domestic and foreign experts and scholars have done a lot of research on the material insulation performance and construction technology of the external wall insulation system,which has become mature.However,the research on the safety and durability of external wall insulation system cannot be ignored.Insulation materials,external insulation mortar paste rate and paste methods,the number of anchor bolts per unit area,etc.are the main factors affecting the connection capacity of the external insulation system.However,there is a lack of research on the seismic safety of external thermal insulation systems.When the main structure is not completely destroyed under the action of an earthquake,the safety of the external thermal insulation system is the focus.Therefore,the research on the seismic safety of building energy-saving external insulation systems has very important practical significance.In this thesis,a three-story,two-span,fully symmetrical reinforced concrete frame structure is designed.Infill walls and phenolic board are pasted on the three external facades,and the external insulation finishes of the external walls are subjected to earthquake simulation shaking table tests.The connection performance between the external thermal insulation system and the base wall is the key to studying the seismic performance of the external thermal insulation system of the external wall.In this experiment,the base wall uses aerated concrete blocks,and the phenolic board external thermal insulation mortar paste rate and paste method are test variables,And use the number of anchor bolts per unit area that meets the requirements of the specification to study the stress mechanism,failure process and failure mode of the external thermal insulation finish layer of the phenolic board under the action of an earthquake.The following conclusions are drawn through experimental research:(1)The infill wall and the external wall insulation system change the stress mechanism of the original frame structure.The facing layer,the infill wall and the original structure are connected and restricted to each other to form a new system of collaborative work,and jointly bear the external seismic load.However,as the seismic intensity increases,the finish layer is separated from the main structure,the infill wall is damaged,and the overall work performance is gradually weakened;(2)The existence of infill walls and external wall insulation systems improves the overall rigidity of the structure,reduces the degree of damage to the structure,and enhances the seismic performance and collapse resistance of the structure.(3)Under the action of horizontal earthquake,the infill wall and the facing layer participate in the work to form a diagonal bracing effect.The facing layer is compressed obliquely along the diagonal of the infill wall,and the facing layer should be damaged at the beam-column nodes.(4)In the case of high intensity,the structural deformation increases,the main frame structure and the infill wall deform inconsistently under the action of the earthquake,and relative displacement occurs,causing cracking and destruction of the facing layer at the joint surface.Due to the inconsistency of deformation,shear stress is generated between the thermal insulation finish layer pasted on the frame beams and columns and the base layer,which will cause bond failure and separation of the finish layer from the base layer.Therefore,the finish layer pasted on the main structure during an earthquake should be Resulting in shedding.(5)The phenolic insulation board material has high brittleness and poor deformability.It should be cracked and damaged.The glass fiber anti-cracking net can limit the development of cracks and ensure that the phenolic insulation board cracks and falls off during an earthquake.(6)The bonding method of the phenolic board exterior wall external thermal insulation finish layer,whether it is the point frame method or the strip bonding method,the damage of the external thermal insulation finish layer is not much different.(7)The phenolic board exterior wall thermal insulation finish layer should adopt two layers of glass fiber anti-cracking nets,and anchor bolts should be appropriately added to the frame beams and columns and fill the corners of the wall to ensure that the finish layer and the base layer will not fall off even if they are separated.Prevent secondary disasters.