Study on the energy efficiency of straw fly ash concrete walls in rural residential buildings

Abstract In order to efficiently utilize agricultural and industrial wastes, and to achieve both resource recycling and building energy efficiency, this study incorporated different dosages of fly ash (10%, 20%, and 30%) and straw (4%, 6%, 8%, and 10%) into ordinary concrete(OC) materials, and the straw was selected from corn straw powder (CSP), corn straw strips (CSS), wheat straw powder (WSP), and wheat straw strips (WSS) which were commonly found in rural areas. The compressive strength of the concrete was tested using the experimental platform, the moisture content and thermal conductivity of the concrete were tested at different air humidity levels (0%, 38.2%, 54.0%, 75.4%, and 97.4%), the functional relationship between straw fly ash admixture and the compressive strength and thermal conductivity of the concrete was investigated, and the energy efficiency of the wheat straw flour concrete walls using F20S6 (20% fly ash and 6% straw) was analyzed. The study reveals that although the incorporation of straw and fly ash makes the concrete strength weaken with the increase of the proportion, the concrete with F20S6 dosage still meets the strength requirements of the wall. Meanwhile, the thermal conductivity decreased with the increase of admixture but increased with the increase of humidity. Applied to rural dwellings, straw fly ash concrete(SFC)walls showed significant energy‐saving advantages.