Research Of Thermal Performance And Energy Efficiency Of Modern Raw Brick Masonry Buildings

The area of loess in northern Shaanxi is rich in resources.Since ancient times,the kiln buildings have used local resources to save energy and material and have basically solved the people's demand for living environment.However,the space utilization of traditional kiln buildings themselves,indoor ventilation and lighting problems have limited their development in modern villages and towns.However,due to the limited design and construction of newly-built residential buildings in villages and towns,most of the external protective structures have not been subjected to effective thermal insulation.As a result,many buildings in urban and rural areas have large heat consumption in winter and poor indoor thermal environment.Therefore,it is necessary to explore a new type of raw soil construction that can retain the excellent thermal performance and ecological characteristics of raw soil construction and meet the modern people's needs for living environment,and integrate traditional construction technologies and new technologies into one.It will provide a sustainable development path for the inheritance and development of raw soil construction in the village and township of Shaanxi and the construction of new countryside.The author participated in the project of “Study of Modern Raw Brick Masonry Technology” by the Shaanxi Provincial Department of Construction.The research team selected the raw material mixed modified materials in the northern Shaanxi region.Based on a large number of different material ratio tests,the modern modified raw bricks were determined.Optimum ratio and feasibility of production process;subsequent determination of properties such as density,moisture content,and strength grade of pressed raw bricks,determination of 3 strength grades of modern raw bricks;resistance to water,corrosion,and frost resistance Determine the durability of modern raw bricks to meet the building envelope material requirements.The research group developed a cement-based adhesive mortar and a facing mud suitable for modern rawmasonry brickwork,which solved the problems of masonry masonry adhesion,exterior wall finishes and waterproofing.Through the quasi-static load test of large-scale masonry,the average compressive strength of masonry under seismic load is 3.93 MPa and the shear strength is 0.39 MPa.In order to study the thermal and energy saving performance of modern raw bricks,the heat transfer coefficient of the modern raw bricks was determined by the laboratory “hot box method”,and the thermal conductivity of the solid raw bricks was calculated to be 0.86 W/m.· K,Hollow raw soil bricks are 0.71 W/m·K.From the application level,this paper aims at the seismic construction and energysaving weaknesses of raw soil construction,and conducts a comprehensive structural research on modern raw-masonry brick masonry construction.Based on the considerations of building energy conservation,this paper proposes the application of modern raw-masonry masonry buildings in northern Shaanxi.The outer wall main body is suitable for 370 mm or 490 mm sandwich insulation.The outer wall thermal bridge part can be coated with heat-insulating materials to reduce heat loss.At the same time,it proposes a suitable insulation structure approach for roofs and windows.In terms of seismic performance,this paper mainly studies the construction methods of tie knots between key components in the foundation and wall to ensure the integrity of the building.This article combines the demonstration project of the project team on the spot in northern Shaanxi,using the methods of building trade-offs to compare the heat consumption indexes of the model farmhouse and the standard reference building during the winter heating period,and evaluate the energy-saving effect of the modern raw and masonry building.Utilizing the non-steady-state heat transfer of the envelope structure,comparing the decay times of the temperature waves of the reference farmhouse and sintered clay bricks with the time delay of the temperature peak,highlighting the modern raw brick masonry construction will help reduce the indoor temperature fluctuations and improve Indoor thermal environment in winter is suitable for promotion in residential buildings in villages and towns in northern Shaanxi.