When the system works at 1 o'clock* (the maximum temperature of the electric heating film table is not over the cold area, the traditional heating method in the long winter, while consuming a large amount of coal resources, the harmful gases such as C2 are discharged, which aggravates the pollution of the atmosphere and the environment. It has caused a greenhouse effect on the earth and poses a great threat to human survival. Recently, China has proposed to use clean resources, increase the proportion of hydropower resources, and reduce the consumption of coal resources. Therefore, how to develop and design environmentally friendly and energy-saving green houses, It has become a big problem that cannot be delayed.
1 Choose an environmentally friendly, safe, economical and durable heating system to meet the needs of future housing environmental civilization. A new type of heating system, namely low-temperature radiant electric heating film heating system, has emerged and has broad application prospects.
The low temperature radiation electric film heating system is one of the world's advanced heating methods. The electric heating film which is the main body of the system is a translucent polyester film which can generate heat after being energized, and uses the ceiling inside the building to transmit heat in a radiation manner, and the sanitary conditions and the comfort standard are high.
Analysis of main features of low-temperature radiation electric heating film heating system 1.1 Increase indoor use area, less maintenance, low maintenance eliminates radiators and pipelines, increases indoor use area, and makes the interior of the room more tidy and beautiful. The electric heating film heating system has a long service life, which is several times that of the conventional traditional boiler heating system, and there are no problems such as run, run, drip and leak which often occur in the conventional boiler system.
1.2 The indoor light environment is good, and the freedom of architectural design can be enhanced to realize low-rise windows. The living room of large space can be made into floor-to-ceiling windows. The sunlight, outdoor greening and landscape can be introduced into the interior. While using solar energy, it is also refreshing. Feel closer to nature.
1.3 Indoor temperature adjustment The room temperature can be adjusted freely within the set temperature range by the thermostat set in each room. It can make people save energy as convenient as water saving and power saving.
1.4 Low cost, economical and reasonable This system can be designed and installed according to the needs of users and decoration engineering. According to different needs, it can be installed in the ceiling or installed on the wall to achieve the dual effects of heating, beautiful and comfortable. Out of the cost of economic rationality.
1.5 Billing is flexible and accurate. It can be divided into households, sub-units or floors. Users can freely control the power consumption and solve the long-term problem of residential heating management in the government and property departments.
1.6 Low temperature operation, safe and reliable accidents such as burns. The whole system is connected in parallel and the operation is stable.
1.7 Indoor small environment without pollution Because electricity is used as heat source and electric heating film is used as heating element, firstly, dense objects such as floor, wall and furniture in the room are heated, and heat is evenly distributed throughout the room. There is no floating dust caused by air convection in the room. , in line with urban health standards.
1.8 Sun-like warm radiation heating, the surface temperature around the room is improved, making people feel comfortable, without the dry and stuffy heat caused by traditional heating methods.
1.9 Water-saving, land-saving, landscaping The exterior of the building has been eliminated from the boiler room, pipe network, coal storage yard, and ash yard, eliminating the need for water, reducing land occupation, smoke-free dust, dust, and beautifying the surrounding environment.
However, at present, the electric film and its accessories used in China mainly rely on imports, so the price is slightly higher. If the domestic development and production can be self-developed, the application prospects will be more extensive.
Since the installation of the electric heating film requires the use of glass wool felt as a heat insulating layer, it is fixed on the ceiling by wood, light steel keel, etc., and the height is about 70 mm, which requires a certain space.
2 Comparison of traditional heating system and electric heating film heating system Social and economic benefits System category Coal-fired boiler fuel, gas-fired boiler, electric boiler, electric heating film, energy-saving, centralized heating, can not be controlled separately, not easy to save energy, control room temperature, economic operation, water saving, waste water, water conservation The space occupied by the large-scale furnace body pipe and other non-furnace pipes and the inner and outer space occupy a certain space to save space pollution, serious pollution, noise, noise, no waste, sound pollution, pollution, no service life, low installation cost, high moderate maintenance cost, low 3 Housing user heating period investment analysis Take the residential area of ​​100m2 as an example, the heating period of a traditional heating method in Harbin is 31.15 yuan/m2, while the heating cost of a heating film heating system is 18 yuan/m2 (energy saving) The wall, room temperature temperature 16~18*C), the new heating in a heating period saves 1.315 yuan compared with the traditional heating. The long-term economic benefits to home users are considerable.
4 Global people pay attention to saving construction energy. People all over the world are more and more clearly aware that burning coal and other fuels are discharged from Guan Weihua, female, in 1952, Shandong Pingdu, a national registered secondary architect, engaged in architectural design. , research and supervision work.
It covers two layers of grass grids. After 10 hours of concrete pouring, it was found that there were some slight vertical cracks on the top surface of the foundation beam and the inclined surface of the large corner. After 24 hours, the width and length of the crack at the corner of the corner were greatly developed, but no new cracks appeared. In addition to the large development of the width and length of the original crack, the top surface of the foundation beam also produced many new cracks. Two days later, the crack at the top of the beam penetrated the entire cross section and extended downward with the beam side. The length of the extension reached 80 mm. After four days, the crack was basically aligned. After seven days, the crack growth rate has been slow, and no new cracks have appeared. The crack width of the beam surface is up to 07mm, the length of the beam side is about 100mm, and the longest is up to 22Qmm. The crack distribution position is basically consistent with the position of the stirrup inside the beam. There are few cracks in the corners of the corners, and the cracks are as wide as 2mim2. The causes of cracks in concrete are many, but the total can be divided into two categories, namely direct acting factors and indirect acting factors (non-direct acting factors). The former refers to the load or load secondary stress; the latter is mainly other factors than the above reasons: such as concrete plastic shrinkage, plastic settlement, heat shrinkage, dry shrinkage, freeze-thaw erosion, steel corrosion, sulfate attack, alkali aggregate reaction, Uneven settlement of the foundation, etc.
According to the geological conditions of the project and the time, extended shape and distribution characteristics of the cracks on the foundation, the direct cracking causes can be excluded. It can also eliminate the causes of uneven settlement of foundations in non-direct acting reasons and some reasons that can be cracked after more than one year, such as: dry shrinkage, freeze-thaw erosion (cracks should be radial or pattern), steel corrosion, alkali aggregate Reaction, sulfate attack. Since the plastic sheet is covered in time after pouring, the water loss is not too fast, so plastic shrinkage is not the main cause of cracking. In addition, the external additive was tested, and no excessive amount of chloride ions and other inorganic salt anions were found, so the cause of the admixture can also be excluded. The reasons for cracking are analyzed from the following aspects.
2.1 Raw materials and mix ratios After testing, there is no cracking factor in the rubber, sand, admixture itself and the adaptability of cement and admixture in the raw materials used for strip foundation concrete. However, although the stone is continuously graded, the larger particle size, especially the particle size of 20 mm or more, is less. This will weaken the proper bite and tie between the coarse aggregate and the cement cement, which is detrimental to the resistance to concrete cracking.
The ratio of water to cement in concrete laboratory is 041, the water consumption in one side is 190Kg, and the slump is 190mm. Since the strip foundation is used for winter construction, although the concrete mixture has a long transport distance, the slump is basically not lost. Moreover, there is no pumping height requirement at the site, so it can be considered that the above water consumption and slump are too large. Due to the operation of the mixing station workers, the water consumption fluctuates greatly, and the measured slump of the concrete before pumping on the site is above 190mm, and the maximum is 220mm. Such a large slump will cause the slurry content of the concrete mixture to be large. It makes the concrete easy to produce large plastic settlement. Plastic settlement of aggregates can be considered as the main cause of cracking of the base surface. This can be seen from the side of the cracked hole, as evidenced by the fact that there are fewer stones in the surface of the base beam. There are many small cells (pores) on the side of the foundation, which also confirms the problem of excessive water consumption.
22 Reasons for vibrating and curing during construction: After checking the on-site construction vibrating record, and observing the concrete vibrating process of other projects, it was found that there was over-vibration. Over-vibration, for the above-mentioned concrete with greater fluidity, the degree of sinking of the aggregate will be aggravated, and the slurry will be lifted up seriously. The crack orientation and distribution from the foundation beam are basically consistent with the position and shape of the stirrup. It also shows that the plastic sinking of the aggregate plays an important role in the formation of the foundation crack. The crack at the corner of the corner is wide and concentrated because there is no steel in the surface.
Reasons for conservation: When the minimum temperature of the concrete is poured, the plastic cloth and the grass grid are covered in time, but the grass grid has been used many times, and the heat preservation effect is limited, which inevitably causes the surface to dissipate quickly. The interior will have a temperature gradient with the outside due to hydration heat, so the heat shrinkage of the concrete is inevitable. Therefore, heat shrinkage plays a role in the generation and development of strip-shaped foundation cracks.
3 Precautionary measures Through the above analysis of the reasons for the early cracking of the pumped concrete for the strip foundation, it is considered that the early cracking of the pumping concrete construction should be prevented from the following aspects.
31 should be selected raw materials, aggregate grading should be reasonable. The cement should be uniform, stable and early shrinkage; the sand should be preferentially coarse-grained sand; the admixture should have good adaptability to the cement, and the inorganic component content which causes the concrete to shrink and deform is strictly limited.
32 mix ratio design, under the premise of meeting the pumping construction conditions, the water-cement ratio should be strictly controlled to ensure that the slump before the on-site pumping can be maintained at 160-180mm, and should not be too large.
33 The number of vibrating points and one vibrating time of pumping concrete during construction should be reduced as compared with ordinary mechanical mixing concrete to avoid plastic sagging caused by over-vibration.
34 Strengthen the maintenance measures such as heat preservation and moisturizing, especially in the dry season, the winter with lower temperature and the spring with large temperature difference; or adopt the addition of fly ash, silica fume and other external additives in concrete to reduce hydration. Heat, reducing plastic shrinkage, shrinkage and heat shrinkage.
Fu Rirong, female, born in 1964, December, Shandong Zhaoyuan, associate professor, master of engineering, is currently engaged in structural engineering.
(Continued from page 59) A large number of G2 and various harmful gases have caused serious damage to the nature on which humans depend. In particular, China’s emissions of C2 have occupied the second place in the world, and G2 emissions from building energy. It accounts for 1/4 of the national energy consumption. With the construction of a large number of buildings, the situation may deteriorate further, and the prospects are worrying. However, it is gratifying that the reduction of C2 and harmful gas emissions and the conservation of building energy have gradually become the choice of people of insight around the world. Only the electric heating film heating system has applied millions of meters in China. The world's application area has exceeded 100 million m2. If the natural resources such as solar energy, water power and wind power can be fully developed, the actual significance will be more profound, and people will usher in a new era of technological heating.
Sipimo Hair Essence SPRAY PLATINUM
Key ingredients: Polygonum
multiflorum, angelica, aloe,
ginseng, tea polyphenols,
flaxseed and other extracts
Capacity: 100ml
Platinum Edition: all kinds of
white haired people
-HERBAL EXTRACT-
Hair Care Essence,Hair Growth Liquid,Hair Fall Treatment,Grey Hair Treatment
Shenzhen Sipimo Technology Co., Ltd , https://www.sipimotech.com