CBR test on fibre reinforced silty sand

Geosynthetic fibres are an established family of geomaterials used in a wide variety of civil engineering applications such as pavement systems. In pavement design, CBR ratio count as an important parameter. This study aims to investigate effect of fibre inclusion on CBR ratio. A series of laboratory investigation were carried out to evaluate effects of reinforcing the sub grade soil in pavement system with randomly distributed plastic fibres. In this study, one type of soil (i.e silty sand) and two type of fibre were used. CBR test were conducted on unreinforced samples as well as reinforced ones at different fibre contents (i.e. 0.1%, 0.3%) and different fibre length (i.e. 10mm , 20 mm and 40mm).The results of CBR test showed that the CBR ratio for reinforced silty sand increased even more than two times in some cases as fibre content and fibre length increased. The results proved that application of short randomly distributed fibre is a good method to apply in practical projects

Effective Parameters on Strength of Reinforced Clayey Sand

Soils and their related behavior has always been the subject of many studies. Recent researches show some interests in investigation of inclusion of randomly distributed fiber in soil. This study focuses on effect of fiber inclusion on the strength and other parameters of clayey sand composite material. The first part of this study is related to effective parameters on strength of the clayey sand composite with using natural fiber and plastic fiber with different fiber contents and length. UCS tests were carried out to investigate behavior of the composite under different condition. The fiber percentage varied from 0 % (for unreinforced samples) to 4% and fiber length varied from 8mm to 25mm. The fiber length and fiber content are found to play important roles in the strength of fiber reinforced composite. Furthermore it was observed that ductility of sample increased by fiber inclusion

Laboratory Investigation on the Compaction Properties of Lime and Fly Ash Composite

Soil stabilization has been implemented for improving soils, which have inadequate engineering properties. Chemical stabilization method is mixing additives, such as lime and fly ash with soil to modify soil characteristics. This paper describes a research that carried out to study the effects of lime and fly ash in compaction properties of sand based on the seven specimens (i.e., 1 sand, 2 lime, 2 fly ashes and 4 mixture of lime-fly ash). The effectively of lime (%1 and %2), fly ash( %5 and %10) ash and the combination of each mixture were investigated in this research study in order to evaluation the maximum dry density and optimum moisture content of sand. The given result of lime and fly ashspecimens illustrated that fly ash stabilization is more effective than lime treatment alone. However, utilization of combination of additives leads to optimum effect on compactability property of sand

Study on the GCL’s Response to Hydraulic Uplift

Most of landfill sites in developed countries employ GCL as bottom liners to replace compacted clay liner. However, various water level and direction might be faced by GCL during its operation. These conditions can make the GLC to deform and decrease its hydraulic capability. In this experiment, the GCL was tested with two direction of water flow to see whether any deformation that causes the GCL to lose its hydraulic performance. The results showed that the hydraulic performance of the GCL was constant while facing a water flow coming from above even some area started to be slightly thinner than others. In contrast, the GCL started to uplift, curved and lost its hydraulic performance when thewater pressure coming from underneath. The bentonite particles also moved aside from higher hydraulic pressure zone into lower pressure area creating diverse thickness

Preliminary Investigation of the GCL’s Boiling toward An Upward Water Flow

The performance of GCL as liquid barrier depends on its hydraulic performance. During its application, the GCL may encounter high water level and opposite water flow from ground water that can cause the failure of the GCL in maintaining its water tight. In this experiment, the high water pressure coming from above pushed the GCL to be thinner in some part and trigger the bentonite powder to escape from its carrier. However, the GCL did not lose its capacity to retain the water flow. Meanwhile, the opposite direction of water pressure applied afterward had a significant effect to the GCL performance after three days. The hydraulic performance of the GCL dropped significantly alongside with some physical changes on the GCL’s cover. The boiling of bentonite was built up during the failure of the GCL

Laboratory Investigation on the Effect of Lime on Compressibility of Soil

Settlement and heave of soils is known as critical problems in civil engineering projects. In order to control this problem, were indicated several technique. Soil stabilization with a binder such as lime is one of the most regular methods. This paper presents a series of laboratory test for investigation and evaluation of lime effect on the compressibility and swelling properties of soil. In this study, the compression index, swelling index, coefficient of consolidation and initial void ratio of one un-stabilized sample and six stabilized samples with variation of lime additives were investigated. Generally, the results of this study indicate that lime stabilization could improve consolidation and swelling behaviour ofsoil, which could reduce the coefficient of consolidation, initial void ratio of soil by adding additives. It was also observed the divers result that was shown the different rate of stabilization effectivity onconsolidation and swelling properties of soil

Laboratory Investigation on the Effect of Fly Ash on the Compressibility of Soil

One of the key steps in geotechnical construction is study on characteristics of soil for evaluation the deficiency factors of soil properties that lead to some problems such as settlement and heave. Soil stabilization with fly ash as by-product is one of the effective methods that were applied for modifying soil properties. This paper presents a series of laboratory tests for investigation on the adequacy of fly ash on the compressibility and swelling characteristic of soil. In this research the compression index, swelling index, and initial void ratio of one un-stabilized sample and eight stabilized specimens with difference fly ash additives were investigated. Overall, the data reveal that fly ash stabilization couldreduce the consolidation property, swelling behaviour. In addition, increment in the amount of fly ash led to reduction in the initial void ratio of stabilized samples

A Review on GCL Performance in Geotechnical Engineering

Over the past decade, geosynthetic clay liners (GCLs) have gained widespread popularity as a substitute for compacted clay liners in cover systems and composite bottom liners. They are also used as environmental protection barriers in transportation facilities or storage tanks, and as single liners for canals, ponds or surface impoundments. As a result, they are being investigated intensively, especially in regard to their hydraulic and diffusion characteristics, chemical compatibility, mechanical behaviour, durability and gas migration. In this paper, a review of the main findings is presented. From this work, a general insight is gained on outstanding effective factors on GCLs’ different performances and will additionally be used to develop GCL applications. An accurate interaction analysis of this system will be a remarkable contribution to the field as it will allow GCLs to be more effectively applied to a wider range of geotechnical issues

Performance of fiber reinforced clayey sand composite

Soils and their related behavior have always been the subject of many studies. Recent researches showsome interests in investigation of inclusion of randomly distributed fiber in soil. This study focuses on effect of fiber inclusion on the strength and other parameters of clayey sand composite material. First part of this study is related to effective parameters on strength of the clayey sand composite with using natural fiber and plastic fiber and different fiber contents and length. Triaxial consolidated undrained (CU) tests were carried out to investigate behavior of the composite under different condition. The fiber percentage varied from 0% (for unreinforced samples) to 4% and fiber length varied from 8 to 25 mm. The fiber length and fiber content found to play important rule on the strength of fiber reinforced composite