This paper discusses the stabilization of clayey subgrade when mixed with coir fibres (CF) randomly and fly ash (FA). The tests were carried out on the locally available clay soil with different proportions of randomly mixed CF and FA. The CF and FA proportions used in the study are expressed in percentage by dry weight of soil. The CF and FA proportions used in the present study are 1%, 1.5% and 2% and 0%, 5%, 10%, 20% and 30% respectively. The tests results revealed that the clayey subgrade stabilized with FA resulted in improvement of strength and California bearing ratio (CBR). Further, it is observed that randomly mixed 1% CF and 20% FA mixture resulted in improvement of CBR of subgrade as compared to clay subgrade treated with 20% FA alone and this increase is noticed as 1.5 times. Overall, it is concluded that 20% FA + 1% CF resulted in improvement of subgrade in terms of CBR.

中文翻译：

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椰壳纤维和粉煤灰的随机混合对黏性路基稳定性的影响

本文讨论了与椰壳纤维（CF）和粉煤灰（FA）随机混合时粘土基的稳定性。试验是在当地有不同比例的CF和FA随机混合的粘土上进行的。研究中使用的CF和FA比例以土壤干重的百分比表示。本研究中使用的CF和FA比例分别为1％，1.5％和2％和0％，5％，10％，20％和30％。试验结果表明，用FA稳定的黏土路基可提高强度和加利福尼亚承载比（CBR）。此外，观察到与仅用20％FA处理的粘土路基相比，将1％CF和20％FA混合物随机混合导致路基的CBR改善，并且注意到该增加为1.5倍。总体，