scholarly journals Undrained Strength Characteristics of Fibre Reinforced Expansive Soils

2021 ◽  
Author(s):  
G. Surya Narayana Kurup ◽  
Sona P. S. ◽  
Luthfa U ◽  
Varsha Manu ◽  
Amal Azad Sahib
Keyword(s):  
Fly Ash ◽  
Expansive Soils ◽  
Uttar Pradesh ◽  
Strength Characteristics ◽  
Fibre Reinforcement ◽  
Polypropylene Fibres ◽  
Swell Index ◽  
Swell Potential ◽  
Granular Pile ◽  
Deccan Plateau

Expansive soils are those whose volume changes take place while it comes in contact with water. It expands during rainy season due to intake of water and shrinks during summer season. Expansive soils owe their characteristics due to the presence of swelling clay minerals. Expansive soils cover nearly 20% of landmass in India and include almost the entire Deccan plateau, western Madhya Pradesh, parts of Gujarat, Uttar Pradesh, Andhra Pradesh, Karnataka and Maharashtra. The properties that describe the expansive behaviour of soils are free swell index, swell potential and swell pressure. This behaviour has an impounding effect on the bearing capacity and strength of foundation lying on such a soil. Some of the stabilization techniques which are currently being used are physical alternations, sand cushioning, belled piers, under reamed piers, granular pile anchors, chemical stabilization, and fibre reinforcement techniques. This paper focuses on improvement in the strength characteristics of stabilized Chittur soil. The commonly used stabilizer for expansive soils is lime. This paper looks upon alternative materials such as fly ash and polypropylene fibres in order to reduce the lime content. It was concluded from the trials that an optimum combination of 1.5% lime, 10% fly ash and 0.2% polypropylene fibres contribut

scholarly journals Effect of Micro Polypropylene Fibre on the Performance of Fly Ash-Based Geopolymer Concrete

2019 ◽  
Vol 9 (1) ◽  
pp. 97-108
Author(s):  
Manoj Rajak ◽  
Baboo Rai
Keyword(s):  
Fly Ash ◽  
Portland Cement ◽  
Mechanical Performance ◽  
Polypropylene Fibre ◽  
Fibre Reinforcement ◽  
Geopolymer Concrete ◽  
Split Tensile Strength ◽  
Polypropylene Fibres ◽  
Durability Properties ◽  
Geopolymer Composites

Abstract Geopolymer offers significant promise to the construction world as a possible alternative to ordinary Portland cement (OPC). Like conventional Portland cement concrete, the matrix brittleness in geopolymer composites can be reduced by introducing suitable fibre reinforcement. A few investigations on fibre reinforced geopolymer composites are available. However there is still a gap to comprehend and enhance their performance. This paper describes the effect of incorporating micro polypropylene fibres on the strength and durability characteristics of geopolymer concrete. The engineering and durability properties like workability, compressive strength, split tensile strength, flexural strength, modulus of elasticity, and sorptivity of geopolymer concrete reinforced with micro polypropylene fibres is presented. The effect of the sulfuric acid attack on Geopolymer Concrete reinforced with micro polypropylene fibres is also discussed. The results show that hydrophobic characteristics of the micro polypropylene fibre led to weak contact with the geopolymer binder and hence weakened the mechanical performance of the fly ash based geopolymer matrix. However significant improvements in durability properties were noted.

scholarly journals Modification of AA Binder Matrix with the Use of PP Fibres – Strength Investigations

2020 ◽  
Author(s):  
Szymon Dawczyński ◽  
Anna Stokłosa
Keyword(s):  
Fly Ash ◽  
Bending Strength ◽  
Waste Product ◽  
Strength Properties ◽  
Laboratory Research ◽  
Fibre Reinforcement ◽  
Polypropylene Fibres ◽  
Strength Tests ◽  
Alkali Activated Binders ◽  
Alkali Activated

The alkali-activated (AA) binders are assumed to be more ecological than ordinary Portland cement (OPC) binders, because of lower energy requisition and lower CO2 emissions during the production processes. The purpose of using polypropylene(PP) fibres in traditional concrete, geopolymers and mortars is to improve strength properties by inhibiting the growth of cracks that usually occur due to shrinkage, as well as improving the mechanical properties. This paper presents laboratory research into the fibre reinforcement impact on the strength properties of an AA binder made of fly ash suspension. In addition to the suspension, which is a waste product from the coal power plant, recycled ground glass and metakaolin were used as the precursors. The chemical activator of the geopolimerisation reaction was prepared using sodium hydroxide and sodium silicate. Five different sets of the prism samples 40x40x160 mm were made (with different PP fibres ratio,  from 0% to 2%  by weight) and then the flexural and compressive strength tests were performed.  The addition of polypropylene fibres increased the bending strength, which produced the beneficial effect of reducing crack propagation in cases of tensile stress occurrence. Keywords: alkali-activated binders, geopolymers, polypropylene fibres, fly ash suspension, bending strength

Experimental Study on Various Mineral Admixtures in Fibre Reinforced Concrete

2019 ◽  
pp. 309-317
Author(s):  
Kavitha E ◽  
Karthik S ◽  
Eithya B ◽  
Seenirajan M
Keyword(s):  
Fly Ash ◽  
Rice Husk ◽  
Power Plants ◽  
Rice Husk Ash ◽  
Thermal Power ◽  
Experimental Studies ◽  
Mineral Admixtures ◽  
Hardened Concrete ◽  
Polypropylene Fibres ◽  
Concrete Production

The quantity of fly ash produced from thermal power plants in India is approximately 80 million tons each year, and its percentage utilization is less than 10%. An attempt has been made to utilize these cheaper materials in concrete production. This thesis aims at investigating the characteristics of fresh concrete and various strengths of hardened concrete made with various mineral admixtures such as fly ash. GGBFS, silica fume. Rice husk ash along with polypropylene fibres in various proportions.  M20 grade concrete is considered for experimental studies with 53grade Ordinary Portland Cement blended with varying percentages of mineral admixtures. The maximum size of coarse aggregate used is 20mm.  Various mineral admixtures such as fly ash. GGBFS.Silica fume. Rice Husk Ash were added concrete in various percentages by partially replacing cement and the optimum percentage of the mineral admixtures will be found.  Based on the obtained values, the admixture with maximum mechanical strength is determined and to this polypropylene fibre is added by varying 0 to 0.5 % by weight of cement to the mix.  The test results obtained were compared and discussed with conventional concrete.

scholarly journals Ground improvement using granular pile anchor system: resistance to heave and uplift pressure

2020 ◽  
Vol 19 (1) ◽  
pp. 403
Author(s):  
Alvin John Lim Meng Siang ◽  
Ehab Hamad Sfoog ◽  
Nahla Naji ◽  
Sim Sy Yi ◽  
Nickholas Anting Anak Guntor ◽  
...  
Keyword(s):  
Moisture Absorption ◽  
Expansive Soils ◽  
Ground Improvement ◽  
Reinforced Soil ◽  
Scale Model ◽  
Small Scale ◽  
Numerical Investigations ◽  
Anchor System ◽  
Pull Out ◽  
Granular Pile

<span lang="EN-GB">Expansive soil is found in many parts of the world where its major drawback is its expansion and shrinking property upon moisture absorption and drying during alternation of rainy-dry seasons. Due to its swelling-shrinkage repeated process, fatigue and distress cause crack to structures. Granular pile anchor (GPA) system is a pioneering technique that is utilised in reinforcing these expansive soils. Granular pile anchor (GPA) system is a pioneering technique that is utilised in reinforcing expansive soils. The GPA provides tensile resistance which arrest the exerted upward forces and hence reducing heave. Previous investigations have only focused on load-displacement relationships by utilizing the pull-out technique. In this technique, an external force pulls the GPA and the corresponding displacements are recorded. The results provide indication of the GPA resistance to the applied force. However, in real conditions the heave and expansion forces were developed as a result of the pressure caused by the water absorption which pushes the entire soil bed in the upward direction along with the GPA. Therefore, this paper is aimed to explore this concept by carrying experimental and numerical investigations on a small scale model for a single pile with a diameter of 4 cm, with lengths of 20 and 40 cm. Ultimately, the reinforced soil exhibits reduction in upward force and heave compared to the unreinforced soil. Also, verifications for the testing shows that the relationship between the upward force and heave exhibits almost linear relationship for both experimental and numerical investigations. Therefore, shallow foundations incorporated with a GPA system proves to effectively lessen the heave that occurs in expansive soils which in turn can solve problems for constructions.</span>

scholarly journals Reuse of Municipal Solid Waste from Incinerated Ash in the Stabilization of Clayey Soils

2020 ◽  
Vol 28 (4) ◽  
pp. 1-7
Author(s):  
B. J. S. Varaprasad ◽  
Jayaprakash Reddy Joga ◽  
Suryaprakash Reddy Joga
Keyword(s):  
Municipal Solid Waste ◽  
Solid Waste ◽  
Soil Stabilization ◽  
Sem Analysis ◽  
Primary Objective ◽  
Municipal Solid Wastes ◽  
Electron Microscopic ◽  
Swell Index ◽  
Swell Potential ◽  
Free Swell

AbstractA useful method for the disposal of waste from an incineration plant is to reuse it for geotechnical and civil engineering applications. The primary objective of this study concerns the reuse of local incinerated ash from municipal solid wastes in soil stabilization. Municipal Solid Waste Incinerated Ash (MSWIA) is blended with soil in various combinations and tested for its Atterberg limits, unconfined compressive strength (UCS), California Bearing Ratio (CBR), and Free Swell Index (FSI). A 1-D Consolidation Test was conducted, and changes in the soil during the test were examined by a scanning electron microscopic (SEM) analysis. The test results showed that there are increments in the UCS and CBR values with the reductions in the FSI, swell pressure, and swell potential of the treated soils.

scholarly journals PROPERTIES OF FRESH POLYPROPYLENE FIBRE REINFORCED CONCRETE UNDER THE INFLUENCE OF POZZOLANS

2003 ◽  
Vol 9 (4) ◽  
pp. 271-279 ◽  
Author(s):  
Hau-yan Leung ◽  
Ramapillai V. Balendran
Keyword(s):  
Reinforced Concrete ◽  
Fly Ash ◽  
Silica Fume ◽  
Setting Time ◽  
Polypropylene Fibre ◽  
Partial Replacement ◽  
Fibre Reinforced Concrete ◽  
Polypropylene Fibres ◽  
Fibre Concrete ◽  
Time Substitution

This paper summarises experimental results of some fresh concrete tests. Polypropylene fibres were added to the concrete mix to produce fibre reinforced concrete. Pozzolanic materials, including pulverised fly ash and silica fume, were used as partial replacement of cement, and their effects on the fresh fibre concrete were reported. Test results showed that the polypropylene fibre reduced the concrete workability significantly by thixotropic effect and decreased the setting time. Substitution of pozzolans also greatly affected the properties. The presence of fly ash increased the workability and setting time but in the presence of silica fume a reverse trend was observed. Empirical equations were proposed.

Synthetic Fibres for Fibre Concrete Composites

1993 ◽  
Vol 305 ◽  
Author(s):  
Dorel Feldman ◽  
Zhihong Zheng
Keyword(s):  
Volume Fraction ◽  
Fibre Volume Fraction ◽  
Dynamic Strength ◽  
Strength Properties ◽  
Fibre Volume ◽  
Fibre Reinforcement ◽  
Polypropylene Fibres ◽  
Fibre Concrete ◽  
Deformation Properties ◽  
General Aspects

AbstractThe use of fibrous reinforcement to improve the strength and deformation properties of concrete is now well established. The concept of fibre reinforcement is to use the deformation of the matrix under stress to transfer load to the fibre. Substantial improvements in static and dynamic strength properties could then be achieved if the fibres are strong and stiff, and loaded to fracture, provided there is, of course, a minimum fibre-volume fraction.Besides fibres like asbestos, glass and steel, different kind of synthetic fibres such as polyethylene, polypropylene, polyamide and others are recently used for cementitious composites.Together with general aspects of synthetic fibre concrete composites, original results concerning the study done on a hybrid composite based on steel and polypropylene fibres will be presented and discussed.

Sign in / Sign up

Export Citation Format

Share Document