14th International Congress on Advances in Civil Engineering-ACE 2020-2021, İstanbul, Turkey, 6 - 08 September 2021, pp.616-623
Geotechnical engineers face various problems while designing the foundations on highly compressible clayey soil
due to poor bearing capacity and excessive settlement. In order to overcome some of these difficulties, many
researchers have concentrated their studies on soil improvement techniques. Recently, soil reinforcement has
considered an effective and reliable technique for improving the strength and stability of soils.
This paper presents an experimental study evaluating the effect of randomly distributed polypropylene fibers on
Maximum dry density (MDD), Optimum moisture content (OMC), and Atterberg Limits (liquid limit, plastic limit,
and shrinkage limit) with different polypropylene fiber contents 0%, 0.5%, 1%, and 1.5% (by dry weight of the
soil). In addition, the effect of Polypropylene fiber on the strength properties (Unconfined Compressive Strength
(qu), Elasticity modulus (Eu)) is investigated.
At the outset, initial characteristics and properties for the studied soil were determined and then compared with
that of samples reinforced with polypropylene fibers for the studied fiber contents (fibrillated polypropylene fiber).
These experiments show that Maximum dry density and liquid limit decrease but plastic limit and shrinkage limit
increase with increasing reinforcement ratios (fiber content), and these changes don't lead to a change in the soil
classification for the studied fiber inclusion with a possibility to be changed for fiber content is greater than 1.5%.
With reference to the unconfined compressive strength test results, it was observed that the undrained elastic
modulus decreased for fiber content greater than 0.5% and the unconfined compressive strength (qu) has been
increased for all studied reinforcement ratios (fiber content). It can be concluded that there is a good potential for
use of polypropylene fiber to reinforce high plasticity clayey soils and considering that 0.5% and 1% fiber content
is suitable for the soil in this study to have a good improvement for unconfined compressive strength properties.