【作者】 张磊；

【导师】 杨柳；

【作者基本信息】 西安建筑科技大学 ， 建筑学， 2018， 博士

【摘要】 作为一种天然建筑材料,生土材料具有绿色环保、成本低廉、制备工艺简单、可循环利用、便于就地取材的优点,尤其适合于资源相对短缺、经济相对落后的地区使用。本文以新疆吐鲁番地区为例,从材料改性和墙体热工性能分析两方面入手,系统研究了生土材料的性能改性及墙体热工性能改善问题。基于新疆吐鲁番地区既有生土民居使用现状、室内热环境和人体热舒适的现场调研结果,梳理出既有生土民居存在的典型问题。分别采用水泥和石灰对生土材料进行改性固化以弥补生土材料在抗压强度和抗冻性方面存在的缺陷。此外,系统地分析了表观密度和改性剂掺量对改性生土材料抗压强度、抗冻性、热性能和湿性能的影响;从机理分析入手,通过对材料结构组成、微观形貌和孔隙结构的测试,深入分析了改性生土材料宏观性能变化的根本性原因,为生土材料的性能改性研究提供了支撑。针对改性生土材料无法使用单一指标进行评价的问题,提出了改性生土材料的性能综合评价方法。其中,以导热系数、比热容、等温平衡含湿量等热湿性能指标作为单一评价指标,基于生土墙体热质迁移控制方程来对各单一评价指标的权重进行确定。采用COMSOL Multiphysics对生土墙体热质迁移方程进行求解,分析不同单一评价指标变化对墙体内表面温度的影响,以该影响程度作为各单一评价指标的权重值。此外,采用实验室测试的方法,对综合评价最优的改性生土材料及对比样进行性能测试,测试结果验证了本文提出的改性生土材料性能综合评价方法的可行性。以性能综合最优的改性生土材料作为墙体材料,通过对比分析,确定采用秸秆保温板作为改性生土墙体的保温构造形式。采用软件模拟的方法,对不同改性生土墙体厚度和保温层厚度下改性生土建筑的室内热湿环境进行分析,结合当地居住者夏冬两季90%可接受温度范围,确定了改性生土墙体的最优厚度值以及保温层的最优厚度值,实现了考虑冬季保温,兼顾夏季隔热的要求。基于改性生土墙体及秸秆保温层厚度最优值,对比分析了秸秆-改性生土民居和烧结黏土砖民居的室内热湿环境。与烧结黏土砖民居相比,秸秆-改性生土墙体良好的保温和隔热性能能够在极端气候条件下为居住者营造出相对舒适的室内热环境。对吐鲁番新型生土民居示范建筑进行了冬夏两季的热环境测试,结果表明,在无任何采暖、空调设备的情况下,示范建筑在冬夏两季均表现出了较好的室内热环境。秸秆-改性生土复合墙体良好的保温隔热能力有效地降低了室外气候对室内环境的影响。更多还原

【Abstract】 Earth material is suitable in rural area which has huge problem of resource and economic shortage as one kind of natural building materials.Its abundant source benefits from direct site-to-service application to reduce the costs.No specialized instrument and specific surroundings are required during the production.This study investigated the majorization of earth building material and improvement on thermal performance of earth wall by both stabilization of earth material and analysis on thermal performance of wall,in the case of Turpan,systematically.Based on the investigation on present situation,indoor environment and living comfort,this study putted forward the typical issues in traditional buildings in Turpan area.Earth building material was stabilized with cement or lime in order to improve the compressive strength and frost resistance of earth material.In addition,the effect of both apparent density and stabilizer content on the properties,i.e.compressive strength,frost resistance,thermal properties and hygroscopic properties,was analyzed.The cause of performance variation of physical properties,which supports the works about stabilization of earth material,was studied by a series of testing,for example structual testing,micromorpholpgy testing and pore structure.The comprehensive evaluation method on properties of earth building material was putted forward to solve the issue that the stabilized earth materials can not to be evaluated by single property.The thermal conductivity,specific heat capacity,equilibrium moisture content were selected as the single index,and the impact point of every single index was determined based on the process of both the heat flux and moisture flux inside the wall.COMSOL Multiphysics was used to calculate the control equation of both the heat flux and moisture flux in order to analyze the effect of single index on the insider surface temperature.The effect was considered as the weight of single index.The properties of the optimazed stabilized earth material were investigated and then compared with comparision samples in order to verify the correctness of the comprehensive evaluation method on stabilized earth material.The optimazed stabilized earth material was sellected as wall material.And the straw insulation was determined as the thermal insulated material.One computer software,Design Builder,was used to eveluate the effect of stabilized earth wall thickness and thermal insulation thickness on indoor hygrothermal environment.The results were indicated that the optimazed thickness of both stabilized earth wall and thermal insulation were determined considering the temperature range of 90 % local residentials acceptable.This study analyzed the variation of indoor hygrothermal environment between straw insulation earth house and fired brick house based on the optimazed thickness of both stabilized earth wall and straw insulation.The results presented that the straw insulation earth house possess better thermal performance in winter and summer than fired brick house.The sited testing of indoor enrironment in demonstration house of new earth residence in Turpan showed that a comfort living condition existed in the demonstration house with no heater and no air condition in both winter and summer.The straw insulation earth wall had a strong thermal performance to decay the effect of ourdoor climate on indoor environment.更多还原