EFFECTS OF SUCTION ON SHEAR STRENGTH AND DEFORMATION OF UNSATURATED SAND IN TRIAXIAL COMPRESSION AND EXTENSION TEST

Abstract Waste material such as used tires is increasing every year, which poses environmental problems. However, such material has been used in several geotechnical applications as alternative lightweight backfill in highway embankments and/or behind retaining walls, providing environmental, economic and technical benefits. These applications require knowledge of engineering properties of soil-tire rubber mixtures. The present study aims to show the possibility of tire rubber usage in sand by evaluating the shear strength and deformability of sand mixed with granulated rubber, in weight percentages between 0 and 50%. The tire rubber content was found to influence the stress-strain and deformation behavior of the mixtures. The shear strength of sand mixed with 10% or 20% tire rubber was higher than that measured for sand only. However, the trend for TRC = 30–50% was different. Samples with a rubber content of 30-50% exhibited a rapid decrease in the stress ratio compared with that of sand. The major principal strain at maximum stress ratio was found to increase with increasing tire rubber content. However, it was observed that the lateral strains (minor and intermediate principal strains) of samples reduced significantly with the addition of tire rubber to the sand.

Download Full-text

Experimental Study on the Influence of Foundation Pit Dewatering on Shear Strength and Deformation of Pit Bottom Soil in Soft Soil Area

Soil Behavior and Geomechanics ◽

10.1061/9780784413388.040 ◽

2014 ◽

Cited By ~ 1

Author(s):

Chunlin Ding ◽

Ying Xu ◽

Xuping Wu ◽

Keliang Wu

Keyword(s):

Experimental Study ◽

Shear Strength ◽

Soft Soil ◽

Foundation Pit ◽

Bottom Soil ◽

Strength And Deformation ◽

Soft Soil Area ◽

Soil Area

Download Full-text

Shear Strength of a Cemented Paste Backfill Submitted to High Confining Pressure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.858.219 ◽

2016 ◽

Vol 858 ◽

pp. 219-224 ◽

Cited By ~ 1

Author(s):

Eduardo Eiler Batista de Araújo ◽

Dragana Simon ◽

Fagner Alexandre Nunes de França ◽

Osvaldo de Freitas Neto ◽

Olavo Francisco dos Santos Jr.

Keyword(s):

Shear Strength ◽

Triaxial Compression ◽

Binder Content ◽

Cemented Paste Backfill ◽

Compression Tests ◽

Mining Operations ◽

Geomechanical Properties ◽

Confining Pressures ◽

Paste Backfill ◽

Curing Method

Deep mining operations require special measures in order to keep safe and economic aspects. After mine ore is extracted, voids are created and need to be filled with high-strength, low-cost materials. Cemented Paste Backfill (CPB) has recently become one of the main alternatives in filling stopes. Although numerous papers have mentioned the magnitudes of the strength of this material, its behavior under high confining pressures is still not well understood. Therefore, the purpose of this study is to increase the knowledge regarding the CPB behavior. Triaxial compression tests were performed using a Hoek Cell and Load Frame System under high confining pressures. Samples with two different binder contents were used in order to obtain the CPB strength improvement. Besides the self-weight consolidation curing method, samples were subjected to a different curing method that simulated a zero gravity condition (rotating wheel) in the first curing day to compare their mixture properties. The results suggested that both curing method and binder content have influenced the geomechanical properties of Cemented Paste Backfill. By increasing the curing time, the CPB shear strength has increased slightly, whereas specimens with higher binder content presented a significant increase in shear strength values.

Download Full-text