Study On Fabrication And Construction Technology Of Precast Lightweight Aggregate Concrete Sandwich Composite Wall Panel

According to statistics,the whole process of domestic building energy consumption accounts for 46.5%of the total national energy consumption,and the building operation phase accounts for 21.7%.Among them,the energy consumption caused by heat transfer from the wall of the envelope structure accounts for 35%～40%of the total energy consumption of the building.It is important to effectively reduce the energy consumption of the building envelope structure to realize green and sustainable development and achieve carbon neutral carbon peak.The current prefabricated exterior wall panels mainly adopt the form of ordinary concrete sandwiching polystyrene panels,which have high self-weight and poor overall structural working performance.In this paper,an energy-saving and decorative integrated prefabricated light-aggregate concrete sandwich composite exterior wall panel is proposed.This includes relevant research around the preparation and basic performance of wall panel materials,production process of wall panels,lifting of wall panels and construction process.The research mainly includes the following four aspects.（1）Preparation of wall panel material and its performance research.The best ratio of Lightweight aggregate concrete（hereinafter referred to as LAC）and Polystyrene granular concrete（hereinafter referred to as PGC）was determined by single-factor analysis through experimental comparison.According to JGJ51,the mixing time,adding sequence and vibrating method of material preparation were adjusted after several trial fitting tests.This included optimizing the preparation process of LAC and PGC that can satisfy the precast wall panels used in this paper.Subsequently,the basic mechanical and thermal properties of the two materials were investigated to verify the feasibility of light aggregate concrete sandwich composite exterior wall panels as a building envelope and to meet the requirements of energyefficient building design.（2）Research on the production process of sandwich composite exterior wall panels.With reference to the conventional wall panel molds,the conventional wall panel molds were optimized for the construction and preparation requirements of light-aggregate concrete sandwich composite exterior wall panels.A design scheme of sandwich composite wall panel mold was proposed,which can effectively improve the precision of wall panel preparation,save cost,facilitate the production schedule of assembly line,and produce prefabricated components for construction and installation.The quality control of sandwich composite wall panel preparation was also suggested.（3）Analysis of sandwich composite exterior wall panel lifting.The force analysis of the lifting state of the members,the theoretical calculation to get the most reasonable lifting point position,and the simulation verification with the help of ABAQUS.Finite element simulation was carried out by ABAQUS for sandwich composite wall panel demoulding lifting and installation lifting by two-point vertical lifting respectively to determine the best position of two-point lifting point when sharing lifting point.（4）Optimal design of sandwich composite exterior wall panel construction process.Based on the characteristics of the light aggregate sandwich composite exterior wall panel itself,the construction process of the wall panel was introduced,and on the basis of the existing construction auxiliary equipment,the wall panel positioning and docking auxiliary equipment was optimized and designed.According to the possible problems in the construction process,the corresponding construction progress control and construction quality control suggestions are put forward.