Effect of polypropylene fibres on the compressive and tensile strength of a soft soil, artificially stabilised with binders

Abstract

This work studies the effect of binder and fibre quantity on the mechanical behaviour of "Baixo Mondego" soft soil, chemically stabilised with binders and reinforced/non-reinforced with short polypropylene fibres. The experimental programme was comprised by four types of tests, one to evaluate compressive strength (unconfined compressive strength test) and three to evaluate tensile strength (direct tensile strength test, split tensile strength test and flexural strength test). The results indicate that increases in binder content cause an increment in the stiffness, the compressive and tensile strength, but have a lower impact on the specimens reinforced with fibres. In general, the addition of a low quantity of fibres to the stabilised soft soil originates a decrease in the stiffness, compressive and direct tensile strength, a reduction of the loss of strength after peak and a change in behaviour, from brittle to more ductile. The results also reveal that the impact of the addition of fibres on the strength depends on the strain mechanism used in each test. Therefore, in flexural strength tests the impact of the fibres is significant, while in the direct tensile strength tests the inclusion of fibres has a negligible effect. Relationships between the compressive and tensile strength are presented at the end of this study, as well as between the tensile strengths evaluated from the direct tensile strength test, split tensile strength test and flexural strength test.

Behavior of cement-stabilized fiber-reinforced pond ash, rice husk ash–soil mixtures

“…Tests results indicated that stiffness and compression strength of sandy soil, increases with cement and fiber content. Correira et al (2015) studied the effect of binder and polypropylene fiber quantity on the mechanical behavior of soft soil; results reveal that the increment of binder quantity improves the stiffness, the compressive and the tensile strength of the soil; however, the presence of fibers may reduce this beneficial effect.…”

Target Reliability Approach to Study the Effect of Fiber Reinforcement on UCS Behavior of Lime Treated Semiarid Soil

“…In order to circumvent the durability issue, synthetic polypropylene fibers having durable life span were used (Consoli et al 2011, Correia et al 2015. The wealth of earlier available literature suggests that both fiber characteristics (including fiber orientation, type, length, thickness, dosage and geometry), nature of clay and type of stabilizer affect the resultant behavior of fiber-reinforced clays (Gray 1970, Gray andMaher 1989;Maher and Ho 1994;Consoli et al 2009;Ahmed et al 2010;Zhu et al 2014;Tang et al 2016).…”

An Investigation of the Uniaxial Compressive Strength of a Cemented Hydraulic Backfill Made of Alluvial Sand

“…The latter implies that the sample is submitted to a stress state of tension along the vertical plane and fails due to the lack of sufficient tensile strength. As geomaterials usually have a higher compressive strength than tensile strength [35][36][37][38][39][40][41][42][43], it can be expected that the UCSes obtained by axial split failure are lower than those obtained by diagonal shear failure. To ensure safe production and successful application of the backfill, the required strength of the cemented backfill must be adequately evaluated.…”