Evaluation of Coir Geotextile Reinforcement for Low-Volume Roads

ABSTRACT

Natural geotextiles play a vital role in the reinforcement and ground improvement of soft compressible soil to enhance soil strength and ensure stability. Of all the natural fibers, coir possesses high tearing strength even in very wet conditions. Hence, in this paper, the efficacy of coir geotextile in improving the functional performance of the pavement and enhancing the modulus of the subgrade soil has been investigated by visual examination and by conducting tests such as Benkelman Beam Deflection (BBD) test, geogauge and static plate load tests on the test sections constructed in the field. The obtained data reveals that the elastic modulus of the subgrade multiplies appreciably when it is reinforced with coir geotextile, thereby helping in increasing the service life of the pavement. Similar results are reflected in the pavement condition survey results as well. The improvement attained in the elastic modulus of the reinforced subgrades is 1.41 and 1.25 times of the elastic modulus of the parent soil, with coir geotextile of mass per unit being 740 g/m² and 365 g/m², respectively. The modified subgrade elastic modulus is given as input to the KENLAYER software and analyzed in order to prepare a design chart for coir geotextile reinforced low-volume roads.

摘要

天然土工布在软压缩性土的加固和地基处理中起着重要的作用, 可以提高土的强度和稳定性. 在所有的天然纤维中, 椰子壳即使在非常潮湿的条件下也具有很高的撕裂强度. 因此, 本文通过外观检查和Benkelman梁挠度 (BBD) 试验, 研究了椰壳土工布改善路面功能性能和提高路基土模量的效果, 在现场施工的试验段上进行的土工测量和静态平板荷载试验. 研究结果表明, 用椰壳土工布加固路基时, 路基的弹性模量显著增加, 从而有助于提高路面的使用寿命. 路面状况调查结果也反映了类似的结果. 加筋路基的弹性模量提高了1.41倍和1.25倍, 单位质量的椰壳土工布分别为740 g/m2和365 g/m2. 修正后的路基弹性模量输入KENLAYER软件, 并进行分析, 以编制椰纤维土工布加固低交通量道路的设计图表.

KEYWORDS:

• Coir geotextile
• reinforcement
• distress survey
• elastic modulus
• low volume roads
• design chart

Acknowledgments

The authors would like to thank Coir Board, Ministry of Micro, Small and Medium Enterprises (MSME), Government of India for their financial support in this research.