| High energy consumption is always an urgent problem during the preparation and applications of building materials in rural. In order to change this condition, resource ecology, industrial waste as well as passive energy saving technology must be utilized to prepare energy saving building materials. A new form of cement was produced by mixing clay, slag and water-glass at room temperature without baking as matrix. PCM building material, dry pressure and wet demould blocks and porous roof material for passive evaporative cooling had been gained by mixed with PCM, straw and foam agent in clay matrix respectively. Mechanical properties, lasting qualities, thermal characteristics and energy conservation properties had been studied and deduced by theory.A new form of cement was produced by mixing clay, slag with prepared water-glass activator during stirring. The preparation of the material is quite different from the normal one, which is produced just at room temperature and without poisonous gas emission. The fabrication of this energy-saving material can be favorable for lowering carbon emission by using recycled industrial wastes and resource ecology in countryside. Compressive strength of 45.3MPa, water resistant coefficient of 0.837, loss factor acid etch of 9.8%, cycle of freezing and thawing for more than 150, high ability of resistant to elevated temperatures and chloride ion, the porosity of 6.76% by mercury intrusion method can be achieved after 28 days curing. Standard curing is benefit for the mechanical properties. The more CaO/SiO2 and activity coefficient, the more strength is. The hydration products were C-S-H with less Ca(OH)2, calcium aluminum and zeolite, which were characterized by XRD, SEM, IR, DTA, NH4+ capacity conversion measurements. Three dimension products model were generated by Materials Studio soft. The results showed that all the products were three dimension reticulated bond jointing structure and there were some cavities in zeolite.A new type of composite for construction named LPM was prepared by mixing clay,slag, alkaline activated agent and a suitable amount of expand perlite impregnated with paraffin as form-stable phase change and latent heat energy storage material which encapsulated with calcium silicate. The dry density of 1674kg/m3, compressive strength of 23MPa, water resistant coefficient of 0.81, thermal coefficient of 0.35 W/(m·K),specific heat of 1.58 W·h/kg-K, thermal storage coefficient of 15.52W/(m2·K), thermal resistance of 1.67 (m2·K)/W, thermal inertia index of 25.91, thermal diffusivity of 0.132×10-3m2/s had been achieved. The variation of temperature with time of LPM and the corresponding traditional material used as reference material were determined. The results indicated that when the environment temperature changed, the temperature of the LPM changed more gently, the temperature fluctuation was less and the peak temperature occurs later than the corresponding traditional material. The energy conservation efficiency can be reach up to 55.6%. In order to improve the coefficient of thermal conductivity of LPM used in winter, graphite had been filling into the clay matrix materials. The zero energy consumption system of PCM building material-polysulfone film-copper net wire-solar energy accumulator had been designed successfully. The solar energy had been converted into electric for produce heat power through copper net wire and was delivered to PCM. The room temperature can be under control in frigidity winter night. The polysulfone film can not only prevent the leakage of PCM but also countercheck the thermal power loss.Two kinds of building blocks had been prepared by putting straw and PCM respectively into the activated clay matrix under the condition of load. The straw building block with the properties of dry density of 1655kg/m3, compressive strength of 25MPa, water resistant coefficient of 0.80 had been prepared. The second one was PCM block with dry density of 1101 kg/m3 and compressive strength of 9.6 MPa. The third one was a sandwich structure with PCM in holes. Heat flow test results showed that the third one was the best with the highest heat resistance, small heat transfer coefficient and the excellent insulation properties. In the same time, a wet demould(demould after 10 minutes) building block had been prepared by a novel designing model and straw, helianthus annuus pith blending into the clay matrix. The size was 240mm×115mm×115mm, pore size was 60mmx60mmx60mm. It can be used for exterior-protected construction and roofs ventilate applications. The calculation of pressure was 584.5Pa and average speed of gas flow through the pores was 2.15m/s.A light weight porous material with suitable strength was developed as a roof material. This material was prepared by choosing slag and clay as raw material, activated by alkali agent and injected with foams. The gelled matrix was then strengthened by adding polypropylene fibers. This unique designed material can detain a significant amount of rainwater and be applied for passive evaporative cooling roof systems. Finally, the porous material with compress strength of 3.3kg/m3, dry density of 453kg/m3, water absorption of 376kg/m3, dry and wet cycle for more than 100 was gained when the W/C was 0.2. The functions of polypropylene can improve the flexural strength by decreasing the stress intensity factor of crack tip and release the stress concentration. The compact pore structure, moderate pore structure and loose pore structure had been studied by SEM and mercury intrusion method. The results showed that the pores structure were intercommunicating pores and the porosity were 51.5%,57.3% and 60.3%, the pore sizes were 20um,40um and 90um。The fractal geometry was applied to describe the pore structures of roof materials with different ingredient ratios. The fractal dimension was 2.97,2.88 and 2.78, which were discovered related to the evaporation cooling performance of the roofs. Larger fractal dimension materials show better water absorption ability. Variations of room temperature and heat flux transfer across porous material roof slab have been measured. The results showed that roof covered with porous material of 30mm can satisfactorily lower room temperature for about 3℃and reduce heat flux, as compared with OPC (ordinary Portland cement) roof layer simply. Covering porous material layer as roof surface can create a more effective cooling system by utilizing its water absorption and evaporation capability during canicule. Thermal coefficient of 0.116W/(m·K), specific heat of 1.08W·h/kg·K, thermal storage coefficient of 3.84W/(m2-K), thermal resistance of 5.63 (m2·K)/W, thermal inertia index of 21.62, thermal diffusivity of 0.237×10-3m2/s had been achieved when the dry density was 453kg/m3. A new mathematics model about the evaporation speed of water in porous materials had been builted combinig with fractal dimension of pore structure.
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