Investigation On The Mechanical And Thermal Properties Of Bamboo Reinforced Lightweight Aggregate Concrete Sandwich Wall Panel

In recent years,China has issued a series of policies to fully support the development of prefabricated building.The prefabrication and ease of installation of steel structure buildings naturally coincide with the concept of prefabricated building.As an important component of prefabricated steel structure buildings,the imperfect development of exterior walls has been one of the main factors restricting the promotion of prefabricated steel structures for many years.Sandwich wall panel is a new type of wall suitable for prefabricated steel structure buildings,which mostly uses metal connectors to connect ordinary concrete on both sides through the insulation layer.It has the disadvantages of high self-weight and obvious thermal bridge effect,and further optimization is needed.This article proposes a sandwich wall panel composed of bamboo reinforced ceramsite concrete,EPS insulation board,and original bamboo connectors.The shear performance of the connectors inside the panel,the out of plane bending performance,and the combination degree of the wall panel are studied through experiments,and the thermal performance of the wall panel is analyzed using Abaqus software.The main content is as follows:(1)A type of bamboo connector was proposed,and four sets of eight shear specimens were made using the connector form and insulation layer thickness as parameters for double shear tests.The shear bearing capacity and load-relative slip curve of each specimen were obtained and analyzed.The results show that the shear bearing capacity of the original bamboo connector with bamboo reinforcement anchorage is more than three times higher than that of the FRP connector,and the connector will not undergo brittle fracture and has good ductility;When the bamboo connector is not anchored with bamboo bars,the bearing capacity is relatively low,and the concrete layer may undergo splitting;When the thickness of the insulation layer is reduced from 70 mm to 50 mm,the average shear bearing capacity of the specimen increases by 13%.(2)An out of plane bending performance test was conducted on 5 bamboo reinforced sandwich wall panels to investigate the effects of different number of connectors,connector forms,and bamboo reinforcement quantities on the bending performance of the wall panels.Theoretical calculations were conducted on the combination degree of each specimen.The results show that compared to FRP connectors,bamboo connectors can effectively improve the stiffness,combination,and bending bearing capacity of sandwich wall panels,and reduce the relative interlayer slip of the wall panels;Increasing the number of longitudinal bamboo bars configured can effectively improve the bending performance of the wall panel;Excessive configuration of bamboo connectors in the wall panel can reduce the bending bearing capacity and combination degree of the wall panel.(3)Abaqus software is used to analyze the heat transfer process of the bamboo reinforced sandwich panel with the insulation layer thickness of 50 mm,and the heat transfer coefficient of the panel is obtained;Studied the effects of the number of connectors,insulation layer thickness,and concrete type on the thermal performance of wall panels,and provided suggestions for the limit number of connectors and insulation layer thickness of wall panels in various climate zones;The heat transfer characteristics of three different types of wall panel are compared,and the applicable thermal division is determined according to the heat transfer coefficient.