Most geotextiles consist of polymers of polyolefin, polyester or polyamide family, which involve environmental problems related to soil pollution. Geotextiles can be used for at least one of the following functions: Separation, reinforcement, filtration, drainage, stabilization, barrier, and erosion protection. Due to the characteristics of high strength, low cost, and easy to use, geotextiles are widely used in geotechnical engineering such as soft foundation reinforcement, slope protection, and drainage system. This paper reviews composition and function of geotextiles in geotechnical engineering. In addition, based on literatures including the most recent data, the discussion turns to recent development of geotextiles, with emphasis on green geotextiles, intelligent geotextiles, and high-performance geotextiles. The present situation of these new geotextiles and their application in geotechnical engineering are reviewed.

Review of Application and Innovation of Geotextiles in Geotechnical Engineering.

Coir is one of the most important natural fibers having significant potentiality in structural biocomposites production. The long coir fiber (LCF) and short fibrous chips (CFC) were extracted from the husk of coconut. The dimensions of the CFC were within 1.0-12.5 mm and the LCF were within 2.0 mm. All the fibers and fibrous chips were treated with 5% NaOH (alkali) before the biocomposite manufacturing. Different percentages (8%, 10%, and 12%) of melamine-urea-formaldehyde (MUF) were used to produce the tri-layered medium density composite panels with 12 mm thickness. The mechanical properties (tensile, flexural, and internal bonding strengths) of coir reinforced multilayered composites has been studied for all the produced biocomposites. The morphological, micro-structural, and bonding mechanisms were investigated by Scanning electron microscope and Fourier-transform infrared spectroscopy analysis. Thermal properties of the biocomposites were studied by thermal conductivity, thermogravimetric analysis, and derivative thermogravimetry characterization. The moisture contents of the final composite panels were also investigated in this study. The main objective of this work is to investigate the influences of MUF on treated coir fiber and fibrous chips reinforced tri-layered biocomposites. Beside, a novel sustainable product is developed through reinforcing the fibrous chip with coir fiber in terms of multilayered biocomposite panels.

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Thermo-mechanical properties of pretreated coir fiber and fibrous chips reinforced multilayered composites

Sustainable pavement construction: A systematic literature review of environmental and economic analysis of recycled materials

Use of environmentally friendly approaches with the purpose of strengthening soil layers along with finding correlations between the mechanical characteristics of fiber-reinforced soils such as indirect tensile strength (ITS) and California bearing ratio (CBR) and as well as the evaluation of shear strength parameters obtained from the triaxial test would be very effective at geotechnical construction sites This research was aimed at investigating the influence of natural fibers as sustainable ones including basalt (BS) and bagasse (BG) as well as synthetic polyester (PET) fibers on the strength behavior of clayey soil To this end, the effects of various fiber contents (05%, 1% and 2%) and lengths (25 mm, 5 mm and 75 mm) were experimentally evaluated By conducting ITS and CBR tests, it was found that increasing fiber content and length had a significant influence on CBR and ITS values Moreover, 2% of 75 mm-long fibers led to the largest values of CBR and ITS The CBR values of soil reinforced with PET, BS, and BG fibers were determined as 1917%, 1543% and 1316%, respectively The ITS values of specimens reinforced with PET, BS, and BG fibers were reported as 4857 kPa, 607 kPa and 4748 kPa, respectively The results of the triaxial compression test revealed that with the addition of BS fibers, the internal friction angle increased by about 100%, and with the addition of PET fibers, the cohesion increased by about 70% Moreover, scanning electron microscope (SEM) analysis was employed to confirm the findings The relationship between CBR and ITS values, obtained via statistical analysis and used for the optimum design of road pavement layers, demonstrated that these parameters had high correlation coefficients The outcomes of multiple linear regression and sensitivity analysis also confirmed that the fiber content had a greater effect on CBR and ITS values than fiber length

Effect of natural and synthetic fibers reinforcement on California bearing ratio and tensile strength of clay

Reinforcing flexible pavements using different types of geosynthetics is a technique that is widely used to increase the service life, reduce the maintenance costs and, guarantee high performance throughout the service life. This paper presents the insights from combined experimental and numerical analysis conducted on organic soil reinforced with coir geotextiles. A series of small-scale in-box plate load tests were performed to investigate the behavior of coir geotextile reinforced high plastic organic soil under circular loading. Tests were conducted on both homogeneous (sub grade alone) and layered configurations. Two types of commercially available woven coir geotextiles viz. H2M5 and H2M6, were utilized to study the contribution of coir geotextiles when used as reinforcement at the interface of sub-base and subgrade layers in enhancing the strength and stiffness of the low volume road. The primary objective of this exploratory study is to investigate the improvement in the performance of the low volume pavement as a result of the added geotextile reinforcement. The key performance parameters, namely, displacement, stress and strain responses of both reinforced and unreinforced pavement sections are obtained by analyzing the pavement using ABAQUS, which is a software suite for Finite Element Method (FEM) analysis. Test results indicate that the coir geotextile reinforcement substantially improved the performance of high plastic organic subgrade. A maximum reduction of 38% and 24% in vertical strain was observed on top of the subgrade in the case of H2M5 and H2M6 coir geotextile reinforced sections, respectively. Also, a maximum reduction of 30% and 18% in vertical displacement was observed in the case of H2M5 and H2M6 coir reinforced sections, respectively. At an average radial distance of about 1 m from the center of simulated static wheel load, very small displacement and strain value were observed for reinforced sections, relative to the unreinforced sections. Hence, the conclusion is drawn that the H2M5 type of coir geotextile contributes more than the H2M6 type to the structural performance improvement of pavements when used as reinforcement.

Performance of coir geotextile reinforced subgrade for low volume roads

In this paper, pavement proposed on soft subgrade (SG) that requires improvement is studied and reported. One of the methods of improvement is reinforcing SG with geotextile. Laboratory studies wer...

Coir Geotextiles for Paved Roads: A Laboratory and Field Study Using Non-Plastic Soil as Subgrade

India has one of the largest road networks in the world, aggregating to about 56 lakh km at present. At sites with inadequate CBR, problems of excessive rutting are very common. In order to overcom...

Long-Term Performance of Rural Roads Reinforced with Coir Geotextile – A Field Study

Coir fiber is a natural fiber extracted from the husk of coconut. Coir geotextiles made from coir fibers which are biodegradable and eco-friendly are a good alternative to polymeric geotextile. Bio...

Sheela Y. Evangeline

Papers

Coir Geotextiles for Paved Roads: A Laboratory and Field Study Using Non-Plastic Soil as Subgrade

Long-Term Performance of Rural Roads Reinforced with Coir Geotextile – A Field Study

Durability Study of Coir Geotextile Embedded in Different Types of Subgrade Soil