Correlation of Strength Influencing Factors of Modified Rammed Earth Wall Materials

Abstract

Abstract: Rammed earth construction is one of the main forms of Chinese traditional local-style dwelling houses building. It has the advantages of locally-produced raw materials, warm in winter and cool in summer, convenient construction, low energy consumption, green environmental protection, and greatly inherited and applied in the construction of beautiful countryside. However, the traditional rammed earth wall material is composed of plain soil, and has some shortcomings such as low strength and poor water resistance, which limits its popularization and application. In order to improve the compressive bearing capacity of rammed earth wall materials, plain soil in the northwest Sichuan region was used as raw material and cement, sand, gravel, fiber and EFS soil stabilizer were used as modified materials. The correlation between the influence factors and compressive strength andmicrocosmic mechanism were studied. The results show that the partial correlation coefficients of age, cement content, total sand and gravel content, EFS soil stabilizer content, fiber type and compressive strength are 0.77, 0.72, 0.68, 0.64 and 0.61, respectively. The increase of cement, sand and gravel aggregate, EFS soil stabilizer content and the increase of age are conducive to improve the compressive strength of specimens. Through XRD, IR and SEM analysis, the cementing products produced by cement hydration reaction are wrapped, filled and connected with the soil particles, resulting in reduced porosity between the overall structures, forming a more compact and stable microstructure, and improving the compressive bearing capacity of the modified materials.

Key words: modified rammed earth, rammed earth wall material, compressive strength, partial correlation analysis, microcosmic mechanism

CLC Number:

TU521

LIU Lei, YAO Yong, ZHANG Lingling. Correlation of Strength Influencing Factors of Modified Rammed Earth Wall Materials[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2021, 40(4): 1286-1295.

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