Research On Reconstruction Technology And Economy Of Envelope Structure Of Huangshan Office Building

In 2020,the urbanization rate in China has exceeded 60%.After the 1990 s,the number of public buildings in China has grown rapidly,and the energy consumption of public buildings has increased a lot.In China,these energy consumption has become the highest proportion of energy consumption in the construction industry.At present,office buildings occupy a relatively high proportion in public buildings in China,both in terms of floor area and energy consumption.Therefore,research on energy efficiency improvement in this part is of great significance.The climate in Huangshan area is special,and the outer envelope of office buildings plays a great role in building energy consumption,indoor environment and outdoor aesthetics.The renovation technology of this part is the key to improve the energy efficiency of office buildings.Therefore,this paper takes the office buildings in Huangshan area as the research object,conducts a systematic study on the office building envelope structure in this area,and gives the best combination scheme suitable for the energy efficiency improvement and transformation of the office building envelope structure in Huangshan area.First of all,through literature and field investigation,the basic information of the existing office buildings in Huangshan area is counted,and then the construction characteristics and thermal performance of the four outer protection structures,such as external window,shading,roof and exterior wall,are analyzed.The status quo of the four single envelope structures of the office buildings in this area is obtained,and the following is an in-depth study based on this.Secondly,in view of the above huangshan area both office buildings each of the four single envelope of the existing problems and the corresponding gives the energy-efficiency renovation scheme suitable for the region,and according to the latest in anhui province of the energy saving in the specification requirements,combining the theory of thermal analysis,shows the roof using XPS plate and the outer wall with EPS board for the minimum thickness of insulation material and its cost,and provide theoretical basis for the following simulation and analysis of economic benefit.Thirdly,according to the energy efficiency improvement and reconstruction schemes of four single envelope structures,a representative model is established by using the software De ST,and the energy consumption simulation analysis of each single transformation scheme is carried out through the control variable method,and the energy saving rate of each scheme is obtained.Based on this,the sequence of the importance of the four single envelope structures in the improvement of energy efficiency is listed as follows: the external window is higher than the shading,the shading is higher than the external wall,and the external wall is higher than the roof.According to the simulation results of energy consumption,the following conclusions are drawn by using economic benefit analysis methods such as static investment payback period and life cycle cost: when the overall replacement of energy efficiency improvement scheme is adopted for the outer window,double-layer insulating glass with medium or Low permeability and low-E film should be selected,and the window frame should be made of heat-broken aluminum alloy.The performance of external shading is better than other shading schemes.When XPS board is selected for the roof and EPS board is selected for the external insulation material for the exterior wall,the thickness of XPS board 60 mm and EPS board 50 mm are the corresponding thickness which has good effect of improving energy efficiency and is the most economical.Finally,according to the current situation of office buildings in Huangshan region,the office buildings that need to improve energy efficiency are divided into three categories.Through the orthogonal experimental design method,the above single renovation scheme is designed into an orthogonal table arranged into a combined scheme.Through simulation calculation,the combination scheme which conforms to the minimum requirement of tradeoff judgment of Chinese and foreign enclosure structure in the latest energy saving code of public buildings in Anhui province is selected.The economic benefit analysis of the selected combination scheme is carried out,and the best combination scheme of these three types of office buildings is given in the aspects of the minimum initial investment,the lowest annual total cost,the shortest payback period and so on.Combined with the application of the scheme in practical engineering,the feasibility of the best combination scheme is verified.