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Highlights • The new type straw block that can be used in solar greenhouse is invented. • The hygrothermal environment of solar greenhouse with new wall is favorable. • The pH of new type straw block is high and mycelia were hard to grow on it. • The new type straw block can recycle straw material and protect clay resource. Abstract New types of straw block (types I and II straw blocks) were developed and applied in the north wall of solar greenhouses. The hygrothermal and fungistatic properties of the new types of straw block were researched, and the thermal and wet environment of a solar greenhouse with a north wall formed from new types of straw block (STG) was measured. The thermal properties of the new types of straw block north wall (ST) were higher than those of a porous clay block north wall (CL). The pH values of the extracted liquids of the types I and II straw blocks were 13 and 11.5, respectively, making it difficult for mycelia to grow on these blocks. At the depths of 0, 80, 160 and 240 mm, the temperatures of ST were 0.5, 0.6, 0.8 and 1.2℃ higher than those of CL, respectively. Compared to the solar greenhouse with a porous clay block north wall (CLG), the air temperature of STG was 0.5℃ higher during nighttime, and the average relative humidity was 5.3% lower during nighttime. The research shows that the STG has better thermal and wet environment characteristics, and it is durable and suitable for the growth of crops. [ABSTRACT FROM AUTHOR]

The goal of this paper is to identify the effects of in-pore transport of liquid water and water vapor as well as phase changes on the hygrothermal behavior of earthen buildings. Indeed, one of the main assets used to promote these constructions is their role in moisture buffering hence temperature and relative-humidity quality controlling. However, there is no clear consensus yet concerning the impact of these phenomena on the global energy performance of the buildings. A coupled model is therefore proposed in this paper, based on heat and mass balances inside the earthen walls, in order to clarify this question. This model considers separately the kinematics of each phase (e.g. liquid water, vapor, dry air and solid matrix), in interaction with each other. It also takes into account the impact of pore water confinement on the liquid-to-vapor phase change, in particular on the resulting latent heat released or absorbed. The model is successfully compared to experimental results on instrumented full-scale rammed earth wall subjected to temperature cycles. It eventually allows identifying the singular hygrothermal behavior of earth material by testing the range of applicability of the simplifying assumptions which are commonly made in function of the permeability of the tested material. [ABSTRACT FROM AUTHOR]