轻骨料混凝土物理力学性能及砌块传热的数值模拟

发布时间：2018-05-25 03:35

本文选题：轻骨料混凝土 + 配合比　；参考：《哈尔滨工业大学》2015年硕士论文

【摘要】：以不可再生能源为主的时代,节能的需求日益旺盛。保温砌块作为轻质、保温的建筑材料也成为了一种比较热门的商品与研究对象。为了研究孔洞对砌块传热性能的影响,本文对使用保温砌块所用的轻骨料混凝土、砂浆进行了研究并对砌块的传热性能进行了模拟。本文使用粘土陶粒、页岩陶粒、炉渣等原料设计并配制了针对不同强度的轻骨料混凝土。通过采用公式估算,一定程度上简化了轻骨料混凝土的配合比设计。制得的轻骨料混凝土均能达到预期的强度要求。其中,以页岩陶粒为原料比采用粘土陶粒能达到更高的强度并保持近似的表观密度。使用两种陶粒的轻骨料混凝土导热系数较为一致,而表观密度更高的炉渣混凝土导热系数比前两者更高。高强陶粒制得的混凝土表观密度最高,其强度与导热系数均高于其它原料。本文使用陶砂与细炉渣颗粒作为部分替代普通砂的原料,用以配制具有保温性能的砌筑砂浆。当上述材料掺量较少时,砂浆性能并未出现明显变化。当掺量逐步增大后,导热系数对应分别下降了53%与34%。比较得出选用合适的粒径并使原料超过一定临界掺量才能得到较低的导热系数。根据数据,采串并联计算方法对一种砌体的传热系数进行了计算。然后,采用热箱法对同样砌体的传热系数进行了测定。实测值同计算值进行比较,得出计算值同测定值仅相差11.5%。表明计算方法估算传热系数是可行的,并且准确性良好。最后本文使用ANSYS Work Bench软件建立砌块的3D模型,对多个砌块模型进行了传热模拟分析。其中相邻两排的纵向肋边缘间距在40mm之上时方能较好地增大热阻。结果表明,纵向肋的对称分布比不对称分布方式更利于热阻提升。孔洞层数增加可以增加砌块内部的形状复杂性,并有效提升热阻。
[Abstract]:In the era of non-renewable energy, the demand for energy conservation is increasingly strong. Thermal insulation block as a lightweight, thermal insulation building material has become a hot commodity and research object. In order to study the influence of holes on the heat transfer performance of block, the light aggregate concrete and mortar used in insulating block are studied and the heat transfer performance of block is simulated in this paper. In this paper, lightweight aggregate concrete with different strength is designed and prepared by using clay ceramsite, shale ceramsite, slag and other raw materials. By using formula estimation, the mix ratio design of lightweight aggregate concrete is simplified to some extent. The light aggregate concrete can meet the expected strength requirement. Using shale ceramsite as raw material can achieve higher strength and maintain approximate apparent density than clay ceramsite. The thermal conductivity of lightweight aggregate concrete with two kinds of ceramsite is consistent, while the thermal conductivity of slag concrete with higher apparent density is higher than that of the former two. The concrete made of high strength ceramsite has the highest apparent density and its strength and thermal conductivity are higher than those of other raw materials. In this paper, ceramic sand and fine slag particles are used as raw materials to partly replace common sand to prepare masonry mortar with thermal insulation. When the content of the above materials is low, the properties of mortar do not change obviously. The thermal conductivity decreases by 53% and 34% respectively. It is concluded that the lower thermal conductivity can be obtained by selecting the appropriate particle size and making the raw material exceed a certain critical content. According to the data, the heat transfer coefficient of a masonry is calculated by the method of series-parallel calculation. Then, the heat transfer coefficient of the same masonry is measured by hot box method. By comparing the measured value with the calculated value, the difference between the calculated value and the measured value is only 11.5%. It shows that the calculation method is feasible and accurate in estimating the heat transfer coefficient. Finally, the 3D model of block is established by using ANSYS Work Bench software, and the heat transfer simulation of several block models is carried out. The thermal resistance can be increased only when the adjacent two rows of longitudinal rib edges are spaced above the 40mm. The results show that the symmetrical distribution of longitudinal ribs is more favorable to the thermal resistance than the asymmetric distribution. Increasing the number of hole layers can increase the complexity of the shape of the block and effectively raise the thermal resistance.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528.2;TU522.3

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