Search Results (4)

As green and low-carbon materials, coir geotextiles have a broad application prospect in soil strengthening. In order to clarify the interface characteristics of coir geotextiles, the pullout test is performed on coir geotextiles by using transparent soil technology. The transparent soil is prepared by using fused quartz as the skeleton particle and the mixture of No. 15 industrial white oil and No. 3 industrial white oil as the pore fluid. The results show that the mechanical response of different pullout tests is basically similar, that is, with the increase in pullout displacement, the pullout force first increases rapidly, then slowly increases to the peak value, and then gradually decreases with the fluctuation. The adhesion of coir-geotextile–soil interface is 5.68 kPa and the internal friction angle is 3.43°. The interfacial friction coefficient of the coir geotextiles is unstable, ranging from 0.2 to 0.6. With the increase in normal stress, anchorage length, and pullout rate, the peak pullout force and the thickness of the shear band increase gradually. Full article

Rainfall-induced soil erosion is a significant environmental issue that can lead to soil degradation and loss of vegetation. The estimated global annual loss increased by 2.5% over 11 years, from 35 billion tons in 2001 to 35.9 billion tons in 2012, mainly due to spatial changes. Indonesia is predicted to be among the largest and most intensively eroded regions among countries with higher soil erosion, regarded as hot-spots higher than 20 Mg yr⁻¹ ha⁻¹. Due to climate change, natural rainfall patterns in the tropical regions have been subject to change, with a lower number of rainy days and increased intensity of precipitation. Such changes trigger more soil erosion due to heavier rainfall kicking up dried soil particles that are exposed in the bare embankments. Unfortunately, there is no prevention available in developing countries due to the lack of availability and high prices of mitigation techniques such as terraces and covering areas with geotextiles or blankets. Erosion control blankets (ECBs) have emerged as a potential solution to mitigate soil erosion. This research article aims to evaluate the effectiveness of sugar-palm-fiber-based ECB in reducing soil erosion caused by natural rainfall. The study investigates the effectiveness of sugar-palm-based ECB in protecting against erosion at the designated embankment. During the three months of typical rainy seasons (February to April 2023), total eroded mass (kg) was collected and measured from two adjacent microplots (10 m² each), one covered with ECB and the other one left as uncovered soil (bare soil). The results indicate that eroded mass is proportional to rainfall, with coefficients of 0.4 and 0.04 for bare soil and ECB-covered embankments, respectively. The total soil loss recorded during the monitoring period was 154.6 kg and 16.7 kg for bare and ECB-covered soil, respectively. The significantly high efficiency of the up to 90% reduction in soil losses was achieved by covering the slope with sugar-palm-fiber-based ECB. The reason for this may be attributed to the intrinsic surface properties of sugar palm fiber ropes and the soil characteristics of the plot area. Sugar palm (Arenga pinnata) fiber has higher lignocellulosic contents that produce a perfect combination of strong mechanical properties (higher tensile strength and young modulus) and a higher resistance to weathering processes. Although the cost of production of handmade sugar-palm-fiber-based ECB is now as high as 4 EUR, further reductions in cost production can be achieved by introducing machinery. Compared to typical ECBs which have smaller openings, sugar-palm-based ECB has larger openings that allow for vegetation to grow and provide it with a lower density. As such, we recommend improvements in the quality of palm-fiber-based ECB via the introduction of further automation in the production process, so that the price can be reduced in line with other commercially available natural fibers such as jute and coir. Full article

Slope stability is one of the crucial factors to consider in every civil engineering project. One widely used method to stabilize slope is the use of polymeric products called geosynthetics. Natural fiber geosynthetics used for geotechnical applications have attracted attention because of their environmental and economic benefits. Coir fibers made into nonwoven geotextiles are utilized in this study as an alternative material for slope stabilization. One drawback of coir fiber geotextiles is their low tensile strength and limited life span due to their susceptibility to environmental factors. This study was conducted to evaluate the effect of mercerization and bleaching treatment on the strength performance of nonwoven coir geotextiles after exposure to conditions simulating biological and chemical degradation. Microscopic images of treated coir geotextiles show the removal of surface impurities that altered the physical components in the fiber. The grab tensile strength results prove that the mercerized coir geotextiles are suitable for field conditions and groundwater exposure. The untreated coir geotextiles showed superior puncture resistance relative to the chemically treated geotextiles. The chemical treatments improved the tensile strength; however, they weakened the puncture resistance of the coir geotextile due to the decrease in thickness. A slope stability simulation conducted using Rocscience Slide2 version 9.017 software proved that coir geotextiles can effectively reinforce slopes, with strength performance almost comparable to that of synthetic geotextiles. Full article

The recent trend in coastal research centers around environmental sustainability, especially in coastal conservation. A seawall typically has three layers, namely core, filter, and hard rubble/concrete armor. In the current study, a two-layered seawall is proposed, comprising a coir geotextile roll from the coastal regions, along with sand encapsulated in a geotextile over an impermeable core. This can be considered as a quasi-soft solution against the traditional, three-layered, hard alternative. The objective of this study is to investigate the combined effect of slope and porosity, of this composite structure, on the wave reflection. The findings show that the composite structure provides less reflection coefficient values compared to traditional rubble mound seawalls. Four orientations and positions of coir rolls with geosynthetic sandbag were tested. The armor layer with coir rolls overlain by geosynthetic sandbags over an impermeable core could be a better alternative, as it increases the hydrodynamic performance by 59% as compared to sandbags, used alone, over an impermeable core on a slope of 1:2. Full article