Research On Thermal Performance Of Prefabricated Concrete Shear Wall Residence In Cold Area

In recent years,the number of prefabricated building has increased dramatically as a new industrialized green building,which is vigorously supported by government.Prefabricated building is assembled by prefabricated components on site,and the enclosure structure has relatively large variety and quantity which needs to be combined according to the corresponding technical requirements in sequence,as the result,prefabricated building produces thermal defects different from traditional cast-in-place structure.Nevertheless,the lack of detection and quantitative analysis of thermal defects of prefabricated building and the deficiency of special energy-saving design standard for prefabricated building has caused prefabricated building’s quality and performance greatly decreased.Therefore,how to minimize prefabricated building’s energy consumption on the basis of guaranteeing the quality of buildings is one of the urgent problems to be solved.Therefore,in this paper,the object of research is prefabricated concrete shear-wall residence in cold area,and research contents mainly include the following four aspects.Firstly,in the paper,the classification,produced location and influencing factors of thermal defects in prefabricated building in cold area have been found through investigating prefabricated concrete building’s construction mode.Meanwhile,the paper analyzed the thermal defects through comparing the thermal performance of typical parts of prefabricated building and traditional cast-in-place building based on infrared thermal imaging method.Then,the overall air tightness of the typical room of the prefabricated building is tested by the gate door method,and the results are compared with the current air tightness standard,which put forward the general problems of thermal performance of prefabricated concrete residence in cold area.Afterwards,the this paper,we analyzed the heat transfer performance of typical thermal bridge parts of prefabricated building in cold area by using ANSYS analysis software,analyzed quantitatively the thermal bridge effect parameters combined the method of thermal bridge line heat transfer coefficient,and studied the influence law of constructional design parameters and construction error parameters on thermal bridge of prefabricated building.Meanwhile,the paper calculated the thermal bridge coefficient calculation formula of the thermal bridge effect joints by fitting.Besides,in this paper,the heat transfer experiment of typical joint of prefabricated concrete residence was carried out by using heat flow meter method,and which verified the accuracy of the heat transfer simulation through error calculation and cause analysis.Finally,in the paper,we proposed the thermal performance optimization design strategy for prefabricated building in cold area from two aspects of constructional design and construction error,which effectively reduced the impact of thermal bridge on energy efficiency.At the same time,the paper studied the effects of thermal bridge generated by different influencing factors on prefabricated building load by using Design Builder energy simulation software.As the result,the total thermal bridge increased the thermal load by 5.55%,and the cooling load by 1.47%.The paper has guiding significance for energy-saving design of prefabricated concrete residence in cold area,which provided a method for quantitative analysis of thermal defects of prefabricated building and provided a basis for the improvement of relevant energy-saving standards.Therefore,while improving the quality of the prefabricated building,the energy consumption of the prefabricated concrete residence in the cold area can be effectively reduced.