Using Rammed Earth Materials for Building-Integrated Passive Air Conditioning

就我们在建筑中使用能源的方式而言，最破坏环境的趋势之一是空调的广泛使用。据称，稳定夯土（SRE）墙可以作为一种“被动”空调的建筑集成形式。这些墙是“建筑一体化”的，因为它们是建筑结构的一部分，并且是承重的。重要的是，它们提供了通过自然吸收热量来被动冷却建筑物的能力。它们可以储存这些热量，并在环境温度下降时（比如夜间）重新散发出来。这种能量储存的特性被称为热飞轮效应，可以大大提高室内舒适度。SRE材料的多孔性与粘土矿物的存在相结合，也使墙壁能够被动地控制建筑物内部环境的湿度，即基于湿度的热轮。到目前为止，还没有针对SRE材料被动式空调性能进行量化的全面研究调查。虽然SRE材料的被动效应之前已经在建筑中被开发和监测，但没有研究发现材料性能如何控制这种情况，如何进一步增加它们，或者如何优化它们。例如，了解如何控制材料特性，从而可以指定被动冷却和除湿，从而使这些特性能够根据建筑物的设计进行定制。未来的潜在结果可能是建筑物可以自己调节空气，这样只需要相对较小的机械建筑服务干预。SRE墙可以使用多种原材料建造，如天然底土、采石场废料和回收破碎骨料。如上所述，确实需要量化这些原材料的相关物理性质。将制作广泛的SRE测试样品，并用于检查土壤分级和成分如何影响一系列热性能和湿蒸汽性能。实验工作将试图优化土壤的分级，然后通过各种其他材料的新添加来增强其物理特性。一旦可以合理地量化给定SRE墙被动控制室内温度和湿度的能力，就可以计算出减少因子，以确定SRE可以提供多少常规空调需求。SRE材料被动式热湿特性的广泛数据库将用于计算机建模软件，如IES Apache和ESP-r，用于建筑性能的动态建模。该模型以及实验室规模的实验测试将通过由工业合作者Earth Structures (Europe) Ltd在大学校园建造的实物大小的SRE测试建筑的全尺寸测试来验证。

One of the most environmentally damaging trends in terms of the way we use energy in buildings is through the widespread use of air conditioning. It is claimed that stabilised rammed earth (SRE) walls can be used as a building-integrated form of 'passive' air conditioning. The walls are 'building integrated' because they form part of the building structure and are load-bearing. Critically, they offer the ability to passively cool a building by naturally absorbing heat. They can store this heat and re-radiate it when the ambient temperature falls such as at night time. This property of energy storage is referred to as the thermal flywheel effect and can greatly increase indoor comfort levels. The porous nature of the SRE material is coupled with the presence of clay minerals that also enable the walls to passively control the humidity of a building's internal environment, i.e. a humidity-based version of the thermal wheel.To date there has been no comprehensive research investigation aimed at quantifying the passive air conditioning properties of SRE materials. Although the passive effects of SRE materials have been exploited & monitored in buildings before, no study has been conducted to find how the material properties control this, how to further increase them, or how to optimise them. For example, knowing how to control material properties such that the passive cooling & dehumidification could be specified would enable these to be tailored to the design of a building. The potential future outcome could be buildings that air condition themselves so that only a relatively small intervention from mechanical building services is required.SRE walls can be constructed using a wide range of raw materials such as natural sub-soils, quarry waste products, and recycled crushed aggregate. There is a definite need to quantify the relevant physical properties of these raw materials as discussed above. An extensive range of SRE test specimens will be produced and used to examine how soil grading & composition affects a range of thermal properties and moisture vapour properties. The experimental work will try to optimise the grading of the soils then look to enhance the physical properties through the novel addition of various other materials. Once the capacity for a given SRE wall to passively control indoor temperature & humidity can be sensibly quantified, a reduction factor can be calculated to determine how much of the conventional air conditioning requirement could be supplied by the SRE. The extensive database passive thermal & moisture properties in SRE materials will be used in computer modelling software such as IES Apache and ESP-r for dynamic modelling of the building's performance. This modelling, along with the laboratory scale experimental testing, will be verified by the full-scale testing of a life-size SRE test building constructed at the University campus by industrial collaborators Earth Structures (Europe) Ltd.