Effects of Fiber Additives on the Desiccation Crack Behavior of the Compacted Akaboku Soil as A Material for Landfill Cover Barrier

Abstract

In the daily and final landfill cover barrier system, the hydraulic properties of compacted soil liners and the strength of soil can be adversely affected by desiccation cracking, resulting in the loss of effectiveness and integrity of the containment system as a barrier. Recently, there is an interest of using fiber additive to overcome the desiccation cracking problem. In this study, the desiccation crack test was conducted to investigate the effect of fiber additive on suppressing desiccation cracks in compacted Akaboku soils. Polypropylene (C 3 H 6 ) fiber was used as an additive material for soil sample. The percentages of fiber used were varied as 0.0%, 0.2%, 0.4%, 0.6%, 0.8%, 1.0% and 1.2% (by dry weight of samples). The soil specimens were compacted under the conditions of maximum dry density and optimum water content. The surficial cracking area was measured to determine the crack intensity factor (CIF) of the soil samples. The desiccation crack test results indicated that the percentage of volume change of the compacted soil specimen decreased with addition of fiber. The change in the soil surface area decreased with increasing in the fiber content (FC), and consequently, the volumetric shrinkage strain decreased. The CIF for the soil without fiber (FC=0.0%) were significantly higher than the soil with fiber additive. The CIF of soil at FC =0.0% decreased from 2.75% to 0.6% for the soil at FC=0.2%. It was also found that the maximum crack depth reaches almost 50% of the thickness of the soil without fiber additive. This study suggests the potential application of the fiber additives to soils as an available method to suppress desiccation cracks encountered in landfill cover barriers.

Effects of Nano-Carbon Reinforcement on the Swelling and Shrinkage Behaviour of Soil

“…The drying process was carried out at a temperature of about 34 ± 2 o C for 10 days using an oven with fan. The surface dimensions of cracks were measured using gauge wires to find the crack intensity factor (CIF) to access the magnitude of desiccation cracks that form in the soils, which is written as (Harianto et al 2008;Kleppe&Olson 1985;Peng et al 2006):…”

“…It is also possible, however, for fibers not to effectively fill the pore spaces or come in full contact with soil particles. In such cases, ɣ dmax would decrease (Harianto et al 2008). It could be then that the inclusion of NCs beyond the optimum limit may possibly result from agglomeration of NC filaments.…”

Soil-water characteristic curves and hydraulic conductivity of nanomaterial-soil-bentonite mixtures

“…cement, lime, fibre, fly ash, and silica fume (Akcanca and Aytekin 2012;Al-Rawas et al 2005;Dash and Hussain 2012;Guney et al 2007;Harianto et al 2008;Kalkan 2009;Miller and Azad 2000;Nalbantoğlu 2004;Rifai 2000;Tastan et al 2011;Walker 1995). In general, these studies have shown that the cracks in the soil can be suppressed but the soil hydraulic conductivity will increase.…”

Hydro-mechanical behavior of polypropylene fiber reinforced expansive soils

“…They have concluded that reinforcement of expansive soils with discrete polymeric fibers potentially offer an alternative method to chemical stabilization techniques and other methods for reducing swell potential. Harianto et al (2008) studied the effect of fiber on the volume change characteristics and dessication cracking of Akaboku soil as a material for landfill cover barrier. It was observed in this study that the addition of fiber decreased the volume change, and the volumetric shrinkage strain.…”