Split Tensile Research Articles

Mechanical properties of basalt and polypropylene fibre-reinforced alkali-activated slag concrete

Alkali-activated materials have received considerable attention in regarding their use as environmentally sustainable alternatives to Portland cement. However, the brittleness and shrinkage cracking of these materials have hindered their wider application. An effective solution to these problems is adding fibre to the concrete. This study investigated the mechanical properties of basalt and PP fibre-reinforced alkali-activated slag (AAS) concrete. A total of 11 mixture groups with different fibre dosages and lengths were created, and 132 samples were subjected to cube compressive, prism compressive, splitting tensile, and flexural strength tests. The influence of the fibre dosage and length on the mechanical properties was determined. Owing to the different strength calculation formulas and large shrinkage of the AAS material, significant differences are observed when the tensile strength of AAS concrete is characterized analysed through splitting tensile and flexural strength tests. For the same fibre length and dosage, PP fibre did not improve the strength of AAS concrete as effectively as basalt fibre did. According to the experimental results, a mathematical method was proposed to determine an optimal solution to the bivariate problem.

Experimental investigation on partial replacement of steel slag and E-waste as fine and coarse aggregate

The wastes from the industries are the major problem in present condition. The recycling of all waste using recycling unit is economically facing many problems. The main objectives of this study is the partial replacement of Steel slag and E-waste from the industrials to find the mechanical strength of concrete. Four mixes with different mix proportion is obtained to find the properties which includes compressive, split tensile and Flexural strength of concrete. The partial replacement of M- sand by steel slag with 10%, 20% and 30% to find the optimum percentage of replacement. Using optimum percentage as constant, the Coarse Aggregate is replaced with certain percentage by E-Waste.

Characterization of mechanical properties by preferential supplant of cement with GGBS and silica fume in concrete

Abstract An attempt is made to replace an ordinary Portland cement by a mineral admixture such as ground granulated blast furnace slag (GGBS) and silica fume in concrete mixes. The research practice is done to find an alternative that could be used as areplacement for cement, which is more reliable for sustainable development and the lowest possible environmental consequences. The research is done by preferential supplant of cement with GGBS and silica fume without using any admixtures for the concrete grade-M30 with varying ground granulated blast furnace slag i.e., 40%, 50%,60% and 10% of silica fume added on itto accelerate the pozzolanic effect as a preferential supplant of cement in concrete. Mechanical properties such as compression, tension, split tensile, and flexural strength test is performed to know the suitable scope of the concrete based on their effectiveness and the amount of cement could be supplanted with ground granulated blast furnace slag and silica fume and also to know the most suitable mechanical properties. Stress–strain behaviors for different mix proportions are comparatively studied and flexural strength of reinforced beams is tested.

Studies on influence of mineral admixture on mechanical properties of CC and SCC

Now a day’s research is more concern on the successful utilization of different mineral admixture so as to cut down the environmental pollution caused by cement industries throughout cement production. Self-Compacting Concrete (SCC) is a new generation concrete has been developed without compromising the strength characteristics with minimum time and labour cost. So to make more economic and environmental friendly concrete, two mineral admixtures (waste products of the industries) i.e. Silpozz and Lime Stone Powder (LSP) were used during this experimental work. The aim of this study is to evaluate the fresh and hardened properties of the conventional concrete (CC) and Self Compacting Concrete (SCC) containing mineral admixtures. Cement is partially replaced with Silpozz and LSP as 0%, 10% and 20% for both CC and SCC. Total ten numbers of concrete mixes have prepared for M30 grade of concrete. Fresh concrete properties of CC have evaluated by slump test and for SCC, slump flow, T500, V-funnel and J-ring test were conducted. Hardened concrete properties were evaluated after 7 and 28 days for compressive, split tensile and flexural strength test. The desired amount of superplasticizer (SP) is used in SCC to make the concrete workable. The test results indicate that the 20% replacement of Silpozz influences the mechanical properties of concrete as compared to LSP replacement.

Impact of Use Septic Tank Sludge for the application as Pozzolanic Material in high performance concrete

The disposal of septic tank sludge (SS) delivered from wastewater treatment plants is progressively getting to be a risk to the environment for includes Organic compounds which are scary to the public health and environment; over-volumes are every day created and deficiency of relevant landfill sites for wastes. This study aims to explore the impact of septic tank sludge as partial substitutions of ordinary Portland cement (PC) within the production of high-performance concrete (HPCs). The water/binder (W/B) ratio of all kinds of blends is fixed at 0.36 with total binder content of 492 kg/m3. The concrete mixtures, in portion, are replaced with 0%, 5%, 10%, 15% and 20% of SS, individually. The impact of SS used to be analyzed through physical and chemical tests. The workability test of HPC was once decided to utilize the slump flow, Meanwhile compressive strength and tensile strength splitting experiments were conducted to investigate the impact of septic tank sludge on the hardened properties of HPC. The results demonstrated that SS may be a responsive pozzolanic material (PM) ; consequently which could be used as PM in concrete mixes. The concrete blend contains 5% cement substitution with SS illustrated to improve hardened properties of concrete at the all-age of specimens evaluated by comparing to concrete control. Sensibly, the substitution of 20 % septic tank sludge is desirable for creating high-performance concrete.

Improving freeze–thaw durability of recycled asphalt-waste pavements with sodium chloride

The use of industrial wastes such as coal fly ash (CFA) and carbide lime (CL) can enhance the long-term performance of recycled asphalt pavements under freeze–thaw conditions as well as reduce consumption of natural resources. Further improvement of the mechanical properties of such blends can be achieved by adding small quantities of sodium chloride (NaCl). Blends of recycled asphalt, CFA, CL and sodium chloride were therefore assessed in terms of their durability to freeze–thaw exposure. Additional splitting tensile tests were performed to evaluate strength improvements after adding sodium chloride. Specimens were moulded with three different dry unit weights and two different lime percentages, and cured for 7 d. The accumulated loss of mass was evaluated as a function of the porosity/lime index, which broadens the applicability of this index by demonstrating it, and influences not only strength but also long-term performance. The improvement in engineering properties provided by sodium chloride was found to be related to the formation of mineral phase thomsonite and to sodium chloride acting as a catalyser.

Strength aspects of High Performance Concrete by using Waste Material as replacement of Fine Aggregate in various percentages

High Performance Concrete (HPC) is becoming extremely popular now a day in applications, which require substantial improvements in structural capacity and resistance to aggressive environments. Several researchers have tried different mineral admixtures like Fly Ash (FA), Silica Fume (SF) and Ground Granulated Blast Furnace Slag (GGBS) in producing HPC. These admixtures are generally by-products of other industries and hence their properties are not identical and it is very difficult to assure the quality. This paper proposes a relatively new mineral admixture called High-Reactivity Metakaolin (HRM) with potential utility in the production of High Performance Concrete. In recent years Metakaolin is identified as a new pozzolanic admixture which is cost effective, cheaper and can also be considered as best alternative to micro silica. To achieve the economy, Metakaolin which is derived from purified kaolin clay is adding with ordinary Portland cement as partial replacement. In additional strength add with Glass fiber to use for ordinary Portland cement. The Fiber used in this investigation is E – Glass fiber made from glass material of size 6mm and 12mm diameter respectively. Except for control concrete, quarry waste fine aggregate was used in all concretes as a partial replacement of natural sand. The effects of quarry waste fine aggregate on several fresh and hardened properties of the concretes were investigated. It was found that quarry waste fine aggregate and waste recycling coarse aggregate enhanced the slump and slump flow of the fresh concretes. But the unit weight and air content of the concretes were not affected. The overall test results revealed that quarry waste fine aggregate can be utilized in concrete mixtures as a good substitute of natural sand. The experimental work comprises of Compressive Strength test, Split Tensile strength test and Flexure test was conducted. In this experimental investigation, M30 grade were obtained by replacing 0 to 15% replacement of quarry dust instead of Fine aggregate, 0 to 10% of Metakaolin added as supplementary in cement. It shows better result in the mix of 7.5% of Metakaoiln, 0.5% of fiber and 10% of quarry dust in concrete.

WITHDRAWN: Development of normal grade concrete using waste rubber

Abstract Recycled waste pneumatic growth was a big environmental concern in recent years as a result of the world’s exponential growth. The decomposition of waste tyres will take more than 50 years, and each year the number of waste tyres is rising. The use of waste rubber in concrete will mitigate this global problem. Rubberized concrete’s mechanical ability, including compressive strength, tensile splitting strength, bending strength etc., may be undesired by replacing natural granules with rubber residues. In this research the performance of concrete Mixtures incorporating GGBS Plain rubber and Reinforced rubber was examined. In the first set cement is replaced with GGBS ranging from 10% to 50%, in the second set coarse aggregate is replaced with 5% to 35% of Plain tyre rubber pieces, in the third set Coarse aggregate was replaced with reinforced rubber, in the fourth set cement and coarse aggregate are replaced with optimum GGBS & Plain rubber respectively and in the fifth set cement and coarse aggregate is replaced with optimum GGBS and Reinforced rubber. Here Plain rubber & Reinforced Rubber pieces are treated in NaOH solution. The immersion of rubber pieces in NaOH Aqueous solution can enhance adhesion resulting in high concrete strength. The concrete with reinforced rubber shows the better results than the concrete with Plain rubber.

Durability evaluation of reclaimed asphalt pavement, ground glass and carbide lime blends based on unconfined compression tests

The use of domestic, industrial and construction waste has been gaining considerable space in recent decades in view of the social and environmental concern in preserving and reusing natural resources. Thus, this article has the premise of studying the use of the mixture of three residues, evaluating the feasibility of using these as a pavement layer. The first residue is the reclaimed asphalt pavement (RAP) coming from the milling of the asphalt coating of a pavement. The second material used is carbide lime (CL), a residue from the production of acetylene gas that will act as a cementing agent. To react with the carbide lime, a third material was also used: the flat ground glass, since it has a high content of SiO2 in its composition. Thus, it is possible that pozzolanic reactions occur with calcium ions in lime, forming cementing compounds and acquiring properties of strength, durability and rigidity. It was evaluated the variation of the carbide lime (3 and 7%), the dry unit weight (19 and 20 kN/m3) and the ground glass (GG) content passing through the #200 sieve (10, 15 and 25%) in front of the unconfined compression, split tensile, durability and rigidity tests. The results show that the effect of each of the selected variables is considered satisfactory to obtain significant results for each of the tests. The porosity/binder index [η/Biv0.28] proved to be adequate for predicting the mechanical behavior of the mixtures, and it was even possible to make correlations between test results. Furthermore, a generalized approach to replace the laborious durability test is proposed, and limitations are observed.

EFFECTS OF CONCRETE OVERLAY JOINT CONDITIONS AND STRAIN RATE ON SPLITTING TENSILE PROPERTIES

In Japan, design ground motion has increased due to the frequent occurrence of large earthquakes. To improve seismic performance, dams and spillway gate piers (hereafter, piers) are being reinforced. The methods used to strengthen them include concrete overlay, jacketing, etc. On their boundaries, there are concrete joints. These joints are designed as integrated bodies. However, although no accidents have been reported, the joints may be a weak point. The purpose of this study is to understand the effects of concrete joint condition, assuming strengthening for dams and piers such as concrete overlay and jacketing. Dynamic splitting tensile tests of concrete specimens joining old and new bodies were conducted. In dynamic splitting tensile tests, the experimental parameters are the condition of joint surfaces in terms of strengthening and strain rate for earthquake ground motion. The conditions of joint surfaces are raw concrete surfaces, chipped surfaces, and surfaces with rebar insertion. Three cases of strain rate are considered, including a static case and two dynamic cases (about 1,000 μ/s and 10,000 μ/s). Test results showed all joint conditions caused a decrease in tensile strength. There was the effect of increasing tensile strength due to strain rate, regardless of joint condition. It was shown that concrete joints without adhesives might be weak points in reinforced structures.

Investigation of Mechanical and Microstructural Properties of Fiber-Reinforced Geopolymer Concrete with GGBFS and Metakaolin: Novel Raw Material for Geopolymerisation

In modern days, one or the way, development of infrastructure plays a major role that decides upon the matrix of our lifestyle. The development of geopolymer concrete (GPC) is an important step towards the production of eco-friendly concrete. The effective usage of fiber content can reduce environmental pollution issues. An attempt was made to study the effect of the blend of metakaolin (MK) and ground granulated blast furnace slag (GGBFS) with Gujcon CFR fiber as secondary reinforcement was added as source material on the performance of GPC to prevent the effects of thermal variation. Fine aggregate, coarse aggregate, sodium hydroxide, nano-silicon dioxide (nano-SiO2), and cement have been used in the present work to make geopolymer mortar (GPM). GGBFS and Gujcon CFR fiber have been replaced with metakaolin an interval of 25%. The ratio of liquid to solid is 0.45 to 0.55, with a rise of 0.05. The samples are tested for split tensile and compression. To identify the surface morphology and phases SEM, XRD and EDAX have been analyzed. It is evident from the result that an equal proportion of source material with liquid to binder ratio 0.5 has yielded the highest mechanical properties.

Effect of using recycled waste glass coarse aggregates on the hydrodynamic abrasion resistance of concrete

This experimental study is aimed at evaluating the hydrodynamic abrasion resistance of concrete produced with recycled waste glass as coarse aggregates. The underwater (ASTM C1138) method is used to test concretes containing 0%, 12.5%, 25%, 50% and 100% glass aggregates as replacement for natural coarse aggregates. To benchmark performance, the abrasion resistance of glass-aggregate concretes is compared with that of a high-strength concrete mixture typically used in coastal defences where abrasion resistance is critical. Further comparison is made with a general application concrete mixture containing crushed limestone coarse aggregates. At 95% confidence, results of the Kruskal-Wallis test show that the use of recycled waste glass as coarse aggregates in concrete at contents of up to 25% does not significantly affect its abrasion resistance. When compared with the typical high-strength mixture with proven field performance, the results of the Kruskal-Wallis test at 95% confidence indicated that abrasion resistance at glass aggregate replacement levels of up to 25% was not significantly different. Concrete produced with 100% recycled waste glass coarse aggregates had comparable abrasion resistance with that produced with 100% crushed limestone coarse aggregates. Additionally, there was a stronger and significant dependence of the abrasion resistance of glass-aggregate concretes on tensile splitting strength in comparison to both compressive strength and modulus of elasticity.

Comparative study on performance of manufactured steel fiber and shredded tire recycled steel fiber reinforced self-consolidating concrete

The major issues related to the environment are the depletion of natural resources and the dumping of waste materials to the open landfill. Waste tire contributes to the latter problem enormously because it requires large space to dump and which may prone to fire hazards (produced harmful gases like carcinogens) when stockpiled. Recycling of waste tire contributes to solving above mentioned issues by using the recovered material like steel fiber and crumbed rubber etc. in the construction industry. This experimental study presents the fresh and harden (i.e. mechanical and durability) behavior of recycled steel fiber (RSF) extracted from the shredded tire in self-consolidating concrete (SCC). To characterize the above properties, a total of seven mixes were prepared, one control mix i.e. SCC with no fiber, SCC with manufactured steel fiber (MSF), and RSF, each of volume fractions of 0.5%, 1.0%, and 1.5% respectively. Fresh properties were characterized by slump flow and J-Ring test, for checking to fill and passing ability respectively. Whereas, the mechanical properties were investigated in terms of compressive, split tensile, and flexural strength. Further, rapid chloride penetration test (RCPT) and ultrasonic pulse velocity tests were conducted for durability and nondestructive test respectively. Optimization results show that SCC with RSF exhibits overall best performance with a 1.5% volume fraction of RSF as compared to SCC with MSF. With R2 ≥ 0.7, a good correlation was found between fresh, Mechanical, and durability properties. Further, based on global warming potential it is beneficial to use SCC with RSF over SCC with MSF having lesser carbon emission. So, the SCC with RSF is a sustainable and economically viable solution over the SCC with MSF.

Study on The Strength Properties of F.R.C with Incorporation of Wood Ash

<p>Cementations materials have been utilized by humankind for development from days of yore. The each rising practical prerequisite of the structures and the ability to oppose forceful components has required growing new cementations materials and solid composites to meet the better and strength rules. The ecological factors and weight of using waste materials from industry have additionally been the major contributory components in new advancements in the field of solid innovation.</p> <p>With the headway of innovation and expanded field of uses of cement and mortars, the quality functionality, strength and different characters of the standard solid need changes to make it more appropriate for a by circumstances. Added to this is the need to battle the expanding cost and shortage of concrete. Under these conditions the utilization of admixtures is discovered to be a significant elective arrangement.</p> <p>Subsequently an endeavor has been made in the current examination to assess the functionality, compressive quality, part elasticity and flexure quality on expansion of wood squander debris (0 – 50%) alongside creased steel strands (0-2%) in concrete. Wood debris is an admixture: a pozzolana. Wood debris is created as a side-effect of ignition in wood-terminated force plants, paper factories, and other wood consuming businesses.</p> <p>The extent of present examination is</p> <ul> <li>To study the usefulness regarding compaction factor of wood squander debris based fiber strengthened cement</li> <li>To study the quality attributes regarding compressive, split tensile and flexure qualities of wood squander debris based fiber fortified cement</li> </ul> <p>Standard shapes of 150 ? 150 ? 150 mm have been projected and tried for getting 7 days and 28 days compressive Strength.</p> <p>Standard chambers of 150mm width and 300 mm tallness were projected and tried for Split rigidity.</p>

An experimental investigation on mechanical properties of concrete by partial replacement of cement with wood ash and fine sea shell powder

Abstract Industrialization and rapid growth of construction activities have escalated economic and environmental concerns in developing countries. In addition to this scenario, million tons of industry and domestic waste is being accumulated and resulted in severe health hazards to human kind and various species. Consequently, research on industry waste and alternative construction materials drawn its attention towards partially replacing cement in concrete which in turn promotes sustainability in construction. Hence, this study was attempted to explore the effect of wood ash and fine sea shell powder by partially replacing cement in concrete of M25 grade. In order to achieve this objective, various mechanical properties of concrete were determined by replacing Ordinary Portland Cement with 5%, 10% and 15% of wood ash and fine seashell powder together. Respective laboratory experiments were conducted to determine basic properties of materials considered for this study and especially to evaluate Compressive, Flexural and Split Tensile Strengths of concrete. The obtained results of these mixes at 7, 14 and 28 days were compared with the test results of conventional concrete. From the analysis of experimental results, it was perceived that wood ash and fine seashell powder have shown favorable effect on concrete mechanical properties.

Experimental research on the anisotropic properties of sandy slate

In this study, the effect of joint on the anisotropy of a homogeneous, stiff, and intact sandy slate from a typical hydropower station is investigated by selecting and making jointed rock samples with jointed angles of 0°, 30°, 45°, 60°, and 90°. Accordingly, an acoustic measurement and a triaxial compression test are conducted on these jointed rock samples. The research results show that the joint angle significantly influences the rock mass anisotropy. In other words, the average value of the longitudinal wave velocity of the jointed rock samples is smaller than that of the intact rock. Furthermore, the value of the longitudinal wave velocity increases with the increase of the joint angle and is the largest when its spreading direction is in line with the joint inclination. The stress–strain curve, elastic modulus, peak strength, and failure mode of the joint rock samples are found to have anisotropic features. The failure stage occurs in samples with joint angles of 0°, 30°, and 90°. The stress–strain curve of the samples with joint angles of 45° and 60° tends to be horizontal. Meanwhile, the elastic modulus and the compression strength displayed a U-shaped distribution with an increase of the joint angle and the smallest value that belongs to samples with joint angles of 30° and 60°. The peak value ratio of the elastic modulus and the compression strength gradually decrease when the confining pressure increases, indicating that the anisotropy of the samples has weakened (i.e., the increase of the confining pressure decreases the anisotropy of the sandy slate strength). The failure mode of the samples with different joint angles is presented as follows: the samples with a 0° joint angle exhibit a tensile splitting damage; the samples with a 90° joint angle exhibit compression–shear damage; the samples with a 30°joint angle exhibit the combination of slide and compression–shear damage; and the samples with 45° and 60°joint angles exhibit slide damage along the joint surface.

Influence of Anti-Slip Aggregate on Properties of Hardened Concrete

Nowadays, applying new materials is widely used in concrete construction to study their effects in enhancing the properties and the durability of concrete. This research includes studying the using of manufactured aggregate, which is so-called '' Anti-slip sand '' in specific proportions to know its influence on strength properties of normal strength hardened concrete which involves compressive strength, flexural strength, tensile splitting strength, and density. Anti-slip sand at different rates of (25%, 50%, 75%, and 100%) replaces the natural sand in the concrete mixture to investigate its effect on the properties of concrete. The study shows that the best results of concrete properties are found when replaced the natural sand by 100% of anti-slip sand. Compressive, flexural and tensile strengths of concrete are increased with increment ratios of (44%, 40%, and 20%) respectively compared with other concrete mixture contains only natural sand. In addition, the study shows that the density of hardened concrete is decreased from 2420 kg/m3 in concrete with 100% natural sand to 2360 kg/m3 with a decrement ratio of 2.5% in concrete with 100% anti-slip sand.

Characterization of deformation behaviour and fracture mode of recycled aluminium alloys (AA6061) subjected to high-velocity impact

Recycling aluminium alloys have been shown to provide great environmental and economic benefits. The global demands placed upon recycled aluminium and its product has further increased the need for better understanding and prediction of the deformation behaviour of such materials subjected to various dynamic loading conditions. It is also a topic of high interest for both the designer and the user of metal structures, specifically in the automotive industry. Even though numerous efforts have been made to improve recycling processes of aluminium alloys, very little attention is given on the fracture behaviour related damage and anisotropy during impact. In this study, therefore, the anisotropic-damage behaviour of the recycled aluminium alloys (AA6061) is examined via Taylor Cylinder Impact test. A gas gun was used to fire the projectiles towards a target at impact velocity ranging from 170m/s to 370 m/s. The deformation behaviour, including the fracture modes, digitized footprint and side profile of the deformed specimens, are observed and analysed. Scanning Electron Microscope (SEM) is further used to observe the damage behaviour, including microstructural changes of the impact surface. The damage progression is also analysed by observing the microstructural behaviour of location 0.5 cm from the impact area. General speaking, there are three different types of ductile fracture modes (mushrooming, tensile splitting and petalling) can be observed in this study within the impact velocity range of 170m/s to 370m/s. The critical impact velocity is defined at 212 m/s. The digitized footprint analysis exhibited a non-symmetrical (ellipse-shaped) footprint where the footprints showed plastic anisotropic behaviour and localized plastic strain in such recycled material. The damage evolution of the material is increasing with the increase in impact velocity.

Experimental Study on Partial Replacement of Msand with Ground Granulated Blast Slag

Solid waste management is the major threat in these days. There are various sources in which the wastes are generated, among those the major role is played by the industries. The industries manufacture a product by giving so many by-products. These by-products are simply dumped in the land which causes pollution. So, it should be treated as well as reused in one form or another. One such by-product is the Ground granulated blast slag which is obtained from the blast furnaces used to make iron. The demand for the construction materials leads to the replacement of new materials in the concrete. Proposed idea is to use the ground granulated furnace slag in the concrete. An experimental investigation is conducted to study the properties of concrete containing the ground granulated blast slag as the replacement of the fine aggregate. The fine aggregate is the manufactured sand. The manufactured sand is widely used nowadays due to the demand and the cost of the river sand. The GGBS is replaced for the manufactured sand by 30%,35%,40% and 45%. Then the strength is obtained by carrying out compression, split tensile and the flexural tests. Then the optimization value of the GGBS is found as 30% and the effect of size of coarse aggregate is found out with the optimized value of GGBS. Then the durability tests are carried out for the acid action due to sulphate, chloride, etc., Finally, the results are discussed and the conclusions are obtained.

Bond behavior between deformed steel bars and cementitious grout

The bond behavior between deformed steel bars and four types of cementitious grout under monotonic loading was investigated in a series of experiments. The effects of testing age and confinement ratio on the bond behavior of the deformed steel bar in the four types of cementitious grout were discussed. The results indicated that the peak bond stress was linearly increased with the increase of time–dependent tensile splitting strength and confinement ratio. The slip at peak bond stress decreased linearly accompanied with the increasing time–dependent tensile splitting strength, and does not seem to be confinement ratio dependent. Moreover, accompanied by the increase of time–dependent tensile splitting strength, the shape parameter of ascending branches of bond stress–slip curves exhibited a linear decrease, whereas the shape parameter of descending branches increased linearly. In addition, with the increasing confinement ratio (1.25 ≤ c/d ≤ 2.5), these two shape parameters stays at a relatively similar values. According to an analysis of the bond behavior of the bond specimens with different test ages and confinement ratios, a peak bond stress model and bond stress–slip constitutive relationships between the deformed steel bars and four types of cementitious grout were proposed. Subsequently, the accuracy of the models proposed in this paper was verified by comparing their results with test results obtained from different sources.