Dynamic Behavior of a Clayey Sand Reinforced with Polypropylene Fiber

Abstract

It is a well-identified fact that more elaborate laboratory studies should be carried out for evaluation of dynamic properties of different types of soils. Regardless of the mechanisms affecting the mechanical behaviour of the soils, past studies reveal that existence of fiber positively affects the strength of either cohesive or non-cohesive soils. A short literature survey provides numerous studies on the stress-strain behaviour of fine/coarse soils, reinforced by polypropylene fiber. On the other hand, studies concerning fiber reinforced soils subjected to dynamic loading are relatively rare. Therefore, in this research it was intended to investigate the effects of polypropylene fiber inclusion on the dynamic behavior of a clayey sand soil, within an experimental framework. In this scope, a number of cyclic triaxial compression tests were conducted to assess the effect of fiber presence. The effects of fiber length and content were experimentally evaluated. Hence, the variation of shear modulus ratio and damping ratio values by shear deformation was plotted to observe the effects of fiber length and inclusion level as well. The results are presented along with detailed evaluations.

Improving the compaction properties and shear resistance of a sand reinforced with COVID-19 waste mask fibers

“…The shortest 15 mm long fibers are presented in Figure 4 . In fact, many authors such as Amir-Faryar (2012) , Amir-Faryar and Aggour (2012) , Noorzad and Amini (2014) , Bozyigit et al. (2017) , Li and Senetakis (2017) , Qadir et al.…”

“…Hence, we targeted a very similar length of 15 mm for the practicality of the manual cutting process. Regarding the values of 30 mm and 45 mm, they were picked since they are the successive multiples of 15 mm, as Noorzad and Amini (2014) and Bozyigit et al. (2017) did in their experiments.…”

“…The predefined fiber content was added in small successive increments. Then, the required weight of water for each moisture content was gradually added and the manual mixing process continued to reach a uniform distribution of fibers within the soil matrix ( Akbulut et al., 2007 ; Tang et al., 2007 ; Amir-Faryar, 2012 ; Amir-Faryar and Aggour, 2012 ; Mirzababaei et al., 2013 ; Bozyigit et al., 2017 ; Tran et al., 2018 ; Wang et al., 2018 ; Sujatha et al., 2021 ). The moist sand reinforced with 15 mm long thin fibers at a fiber content of 0.2% is presented in Figure 6 .…”

“…It was decided to first mix fibers with the dry soil to avoid the fiber clumping which is usually observed when fibers are immediately added to wet soil samples ( Mirzababaei et al., 2013 ; Bozyigit et al., 2017 ). When this mixing method is adopted, fibers become coated by a layer of dry fine soil particles.…”

“…Nowadays, the design and construction of many civil engineering projects require incorporating weak soils with very low bearing capacity and shear resistance ( Mirzababaei et al., 2018 ). Therefore, it is extremely necessary to use various ground improvement techniques of which reinforcing soil deposits with discrete randomly distributed fibers is an attractive method that has recently become a focus of interest ( Tang et al., 2007 ; Amir-Faryar and Aggour, 2012 ; Hejazi et al., 2012 ; Mirzababaei et al., 2013 ; Baruah, 2015 ; Bozyigit et al., 2017 ; Qadir, 2017 ; Qadir et al., 2017 ).…”