Study On The Mechanical Properties Of Fiber Reinforced EPS Thermal Insulation Materials And The Seismic Behavior Of Composite Wall With Thermal Insulation And Load-bearing

In recent years,the state has paid more and more attention to the building energy efficiency,and it has important practical significance to develop the green building with the increasingly high thermal performance requirements of the building envelope.Precast concrete structures’ structural insulation system is one of the effective ways to realize the building energy saving and emission reduction and develop the green building.Based on the previous research results of the research group,this paper focuses on the relationship between the factors and performance of fiber reinforced EPS insulation materials,the mechanical properties and damage constitutive model of fiber reinforced EPS concrete,and the different parameters Composite wall of the seismic performance and thermal performance indicators launched a systematic study and discussion.The main research contents and achievements are as follows:1.From the point of view of optimizing the ratio of fiber reinforced EPS insulation mortar,focuses on the influence of EPS particle content,powder content,silica fume content,hydroxypropyl methyl cellulose ether,water repellent,water reducing agent,fiber content(the ratio of polypropylene fiber and wood fiber were mixed by 1: 1)on the physical,thermal and mechanical properties of EPS insulation mortar and the primary and secondary order of the influencing factors.Inferred the proportion of insulation materials apply to EPS mortar sandwich insulation composite wall.2.Based on the orthogonal test results,focuses on the influence of sand rate on the mechanical properties and thermal performance of fiber reinforced EPS lightweight aggregate concrete was studied by using the single factor method.Inferred the optimum mix ratio of EPS lightweight aggregate concrete suitable for assembling composite wallis obtained,the conversion relationship between the compressive strength of the cube and the compressive strength of the axial and the stress-strain curve.Research indicates:1)With the increase of the sand rate,the compressive strength and the compressive strength of the fiber reinforced EPS lightweight aggregate concrete are increased in different degrees,and the thermal conductivity is reduced;2)Fiber reinforced EPS lightweight aggregate concrete has obvious elastic-plasticity in the compression process,with good deformation energy storage capacity,stress-strain curve include elastic,collapsed platform,and strain softening three stages;3)Based on the theory of continuous damage mechanics and plasticity theory,taking into account the coupling relationship between plasticity and damage,the paper presents the effect of EPS lightweight aggregate concrete under uniaxial compression based on the theory of stress and strain curves of fiber reinforced EPS lightweight aggregate concrete.The constitutive model of plastic damage is verified by comparison with the experimental results.3.The seismic performance of the precast composite wall with three different parameters(filled with aerated concrete blocks,filled with EPS lightweight aggregate concrete blocks and EPS mortar sandwich insulation)was studied to study the effects of different parameters on composite walls Stress characteristics,damage mechanism and seismic performance index;According to the relevant energy saving standard,infer the calculation formula of the heat transfer coefficient and the thermal inertness index of the precast composite wallboard,and the thermal performance indexes of the composite wall with different parameters are analyzed.The results showed that:1)Under the action of horizontal load,the blocks,ribs and outer frame columns in the assembled composite wall can work together to bear the main force in the elastic stage,the elastic-plastic stage and the failure stage of the wall,With multi-channel anti-seismic line;2)Compared with the standard wall,the composite wall filled with EPS lightweight aggregate concrete block improves the cracking load,ductility and energy dissipation capacity of the wall,but the overall bearing capacity of the wall decreases;EPS mortar sandwich insulation composite wall of the energy consumption and the overall load capacity are significantly improved,but the ductility is reduced;3-fitting composite wall has good elastic-plastic deformation ability and anti-collapse ability;3)The ribs of the composite wall structure has strong heat transfer capacity and strong heat flow.The composite wall panel which simply rely on filled with insulation material block can not meet the requirements of building energy saving;EPS mortar sandwich insulation composite wall can better meet the hot summer and cold winter area of building energyefficiency standards,and can be applied to the Xi’an area of building energy efficiency design.