Use of Sawdust Fibers for Soil Reinforcement: A Review

Abstract

A frequent problem in geotechnics is soils with inadequate physical–mechanical properties to withstand construction work, incurring cost overruns caused by their engineering improvement. The need to improve the engineering properties of soils is not recent. The most common current alternatives are binders such as cement and lime. The climate change observed in recent decades and the uncontrolled emission of greenhouse gases have motivated geotechnical and geoenvironmental researchers to seek mechanisms for soil reinforcement from a more sustainable and environmentally friendly approach by proposing the use of recycled and waste materials. An alternative is natural fibers, which can be obtained as waste from many agro-industrial processes, due to their high availability and low cost. Sawdust, as a by-product of wood processing, has a rough texture that can generate high friction between the fiber and the matrix of the soils, leading to a significant increase in its shearing strength and bearing capacity. This concept of improving the properties of soils using natural fibers distributed randomly is inspired by the natural phenomenon of grass and/or plants that, when growing on a slope, can effectively stabilize the said slope.

Experiment and Analysis of Variance for Stabilizing Fine-Grained Soils with Cement and Sawdust Ash as Liner Materials

“…However, the slight PI rebound beyond threshold proportions mirrors the trends reported by Olutoge et al [64] with cement-rice husk ash mixes, hypothesized to be due to excess ions hindering interparticle bonding. Similar non-linear effects on plasticity parameters have been noted in other studies evaluating cement-agriculture waste ash combinations [12]. The decreasing PI trends authenticate that incorporating calculated dosage of binder or binders helps to bridge the liquid and plastic limits, shrinking the moisture zone prone to volumetric instability, and corroborating past studies [65].…”

“…This effect is related to the pozzolanic additives' replacement of clay mineral fractions, coupled with their intense water demand for hydration reactions, as Biricik et al explained [65]. Comparatively, cement has a more pronounced decreasing effect on PI due to its excellent moistureabsorbing properties, as Kolias et al hypothesized [12]. The addition of 6% cement and 6% SDA results in the lowest PI, proving the existence of an ideal clay-cement-SDA formulation blend where both additives work in interaction to modify the clay structure significantly.…”

“…Therefore, improving the geotechnical properties of clay liners, such as strength, permeability, and shrinkage, is necessary to enhance their effectiveness and reliability [8][9][10]. One of the methods to improve the quality of clay liners is to stabilize them with additives, such as cement and sawdust ash (SDA) [11,12]. Cement is a common stabilizing agent that can increase the strength and reduce the permeability of clayey soils.…”

“…Previous research has shown that the amendment of cement stabilization with sawdust ash has led to significant strength benefits in expansive and soft clayey soils [12]. Studies have also focused on the environmental impact of using sawdust ash as a stabilizer for expansive soils, emphasizing the need for soil stabilization due to high plasticity [25].…”

Optimizing Polymer-Stabilized Raw Earth Composites with Plant Fibers Reinforcement for Historic Building Rehabilitation

“…These materials have been used since ancient times in civil construction. Great ancient constructions belonging to different civilizations throughout the world have been preserved and maintained to date and are the subject of great interest in the world of the ongoing search for a healthy life in a biological and biodegradable environment [13]. This process aims to preserve the historical and cultural character of these buildings while improving their durability, structural stability and ease of use [14,15].…”