High Light-transmitting Concrete(LTC)and Its Energy Saving And Mechanical Properties

Green building and building energy saving have become the main development direction of international construction industry,and are also important engines to promote the sustainable development of energy in China.Green buildings can not only save energy and reduce environmental load,but also provide more comfortable and healthy space environment for people.Green building materials are the important foundation and support of green building development.Only by developing and applying green building materials can we build green buildings and achieve the goal of energy saving and environmental protection.As a result,a new green building material—" transparent concrete "came into being.It is a kind of composite material that distributes the transparent material evenly in the concrete,which can pass through the light and make the concrete very bright and transparent.The transparent concrete not only changes the dull,dark and huge monotonous effect of the traditional wall by virtue of its good beauty and decoration,but also its good transparency and thermal insulation performance can achieve building energy saving.In order to promote the popularization and application of transparent concrete,this paper studied its basic properties,analyzed the heat transfer mechanism of transparent concrete wall and its influence on indoor environment and building energy consumption,and studied the seismic performance of transparent concrete wall.The main conclusions are as follows:(1)In order to achieve the industrial production of transparent concrete,an engineering construction equipment and construction method of transparent concrete were developed independently,and the preparation technologies of transparent concrete with various transparent materials were refined.A prediction model of transmittance of transparent concrete was established by using optical analysis software ZEMAX in order to obtain the relationship between the transmittance of transparent concrete and the spatial distribution of optical fiber and the calculation expression of transmittance.Glass fiber reinforced transparent concrete was prepared with glass fiber mesh cloth,and the basic properties were studied by related experimental methods.The results show that the transparent concrete can completely penetrate the visible and infrared light.Besides,the light transmittance of transparent concrete is closely related to the fiber spacing and fiber radius.The compressive strength,frost resistance and impermeability of transparent concrete are obviously improved after adding glass fiber mesh cloth,and the integrity and ductility of transparent concrete are improved obviously.(2)By combining experimental research with ansys software numerical simulation,the thermal insulation and weathering resistance of transparent concrete wall were analyzed.The results show that the temperature stress and deformation of the transparent concrete wall are less than that of the ordinary wall,which indicates that the transparent concrete wall has good thermal insulation effect and can reduce the risk of wall cracking.The stress and deformation of transparent concrete wall is smaller than that of ordinary wall,whether it is high temperature-drenching stage or heating-freezing stage.It shows that the transparent concrete wall can reduce the risk of empty drum and crack and improve the durability of the wall under the condition of resisting the change of bad weather.(3)By combining experimental research with ANSYS Fluent and ECOTECT software numerical simulation,the influence of transparent concrete wall on indoor environment and building energy consumption was analyzed.The results show that the indoor temperature distribution of transparent concrete room is more uniform than that of ordinary room,and its indoor temperature is closer to the comfortable temperature of human body.The lighting level in the transparent concrete room is obviously higher than that in the ordinary room,and the average illumination can be nearly doubled.Under the condition of artificial lighting,the overall illumination of the transparent concrete room is 34.4%higher than that of the ordinary room,and the lighting time is 45.3%lower than that of the ordinary room.Transparent concrete wall can significantly improve indoor comfort by 24.7%,and dissatisfaction PPD reduced by 34.5%.In the coldest day,the energy consumption of transparent concrete house is reduced by 14.2%,and the heating energy consumption is reduced by 20%,which indicates that the energy saving effect of transparent concrete wall is obvious,especially for cold areas with good sunshine conditions in Dalian area.(4)ABAQUS was used to simulate the non reinforced transparent concrete wall,reinforced translucent concrete wall and fiber reinforced translucent concrete wall.The results show that the crack width of the unreinforced transparent concrete wall is large,showing obvious "x" shape failure under the vertical force.After reinforcement,the transparent concrete wall not only improves its compressive capacity,but also improves its brittle failure characteristics.Horizontal distribution of GFRP mesh can improve the bearing capacity and integrity of transparent concrete wall.Under low repeated loading,it is found that the bearing capacity,ductility and energy dissipation capacity of unreinforced transparent concrete wall are the worst,while reinforcement and horizontal distribution of GFRP mesh can significantly improve the deformation and seismic performance of transparent concrete wall.GFRP mesh cloth plays a good role in inhibiting the rapid expansion of wall cracks.With the increase of reinforcement ratio,the energy consumption of GFRP reinforced transparent concrete increases by about 32%,79%and 138%respectively,which indicates that the seismic performance of reinforcement method of steel bar and GFRP mesh cloth is the best.