Numerical Analysis of Splitting Tensile Strength of Steel Fibre Reinforced Concrete under Static Loading

This paper presents the study on the numerical analysis of splitting tensile strength test of steel fibre reinforced concrete under static loading. ABAQUS FEM software is used to model the test configuration for plain concrete and steel fibre reinforced concrete (SFRC) based on the experimental investigations that studied the effectiveness of adding steel fibres of 1.5% volume fraction into the concrete mix. Four 3D models are created which are brick concrete, brick SFRC, stone concrete and stone SFRC. The numerical analysis results are compared with the published experimental results in terms of splitting tensile strength, tensile stress-strain relationship and tensile damage. The splitting tensile strengths from horizontal stress output are found to be slightly lower compared to the experimental results with percentage difference of less than 15%. While the results from using analytical formula also underestimate the splitting tensile strength with percentage difference up to 22% when compared to the experimental results. Elastic modulus from tensile experimental results should be taken as Young’s modulus of the model since it gives results that are closer to experimental results. The Poisson’s ratio that gives the closest results to the experimental result is taken as the Poisson’s ratio of the concrete and SFRC. The adopted 3D model captured reasonably well the reaction of the concrete cylinders subjected to splitting tensile test. Numerical analysis displays a strong correlation with the experimental results after proper evaluations and realistic optimizations of the governing parameters through extensive analyses

Experimental Investigation of Ultrasonic Pulse Velocity (UPV) Test Specimen in assessing the Strength of Steel Fiber Reinforced Concrete Structure

This study aims to conduct the Ultrasonic Pulse Velocity (UPV) test and compressive strength test of Steel Fiber Reinforced Concrete (SFRC). This paper also examines the correlation of UPV test data and compressive strength test data for SFRC specimens. The experiments were carried out with the same value of the water-cement ratio, superplasticizer but different fiber volumes of steel fiber. Twelve prism sizes 100mm x 100mm x 500mm were casted and 0.5%, 1.0%, and 1.5% of steel fiber reinforced concrete were added and the prisms undergone curing for 7, 14 and 28 days. The highest value of the UPV test at the x-axis is SFRC-0.5%, 6.26 km/s at seven days and 6.8377 km/s at 14 days. The highest value of the UPV test at the y-axis is SFR-0.5%, 6.68 km/s at seven days and 6.34 km/s at 28 days. The grading is still in the excellent concrete quality based on BS1881. The highest value of compressive strength is SFRC-1.0%, 193.2 MPa at 14 days. The R-squared value for the correlation coefficient between UPV result and the compressive strength result at the x-axis and y-axis is 0.9963 and 0.9966 respectively which is near to 1.0 and can be considered as strongly correlated. The correlation equation obtained can be used to predict compressive strength based on UPV data for steel fiber addition up to 1.5% volume.  Thus, it can be concluded that percentage of steel fiber added, affect the strength of the tested concrete specimens and the optimized value of steel fiber added is at 1% in this stud

X-Ray Fluorescence, Strength Testing and 3D-Analysis of Steel Fibre Reinforced Concrete Specimen

This study was focused on steel fiber reinforced concrete (SFRC) specimens subjected to X-Ray Fluorescence (XRF), flexural strength testing, Compressive Strength Test and Rebound Hammer Test method. The experimental result of compression strength was analyzed by 3D Analysis using Stat-Ease Design-Expert V13 to correlate the compressive strengths and compare it to the elemental composition of the concrete structure. The result showed that the amount of Calcium Oxide (CaO) in the sample was lower than the composition of Ordinary Portland Cement (OPC) used. Decreasing of calcium oxide for increase proportion of steel fibre samples show the reaction of cement behaviour into concrete properties mixed with other material properties. Thirty-six (36) beam samples 100mm x 100mm x 500mm and twelve (12) cube samples of 100mm x 100mm x 100m were prepared with a different portions of steel fibre and RC structure as control samples. The percentages of steel fiber used were 0.5%, 1.0% and 1.5% to determine the optimum dosage. All samples were cured for 7, 14 and 28 days. It can be concluded that the analysis shows a low significant effect at an early aged concrete but showing a slightly increased in compression and flexural strength at later age

Analysis of corrugated web beam to column extended end plate connection using LUSAS software

Bolted extended end plate connections are commonly used in rigid steel frame. Inappropriate or inadequate connections of beam and column are hazardous and can lead to collapses and fatalities. Although laboratory testing is more accurate in analyzing the connection, but unfortunately it is time consuming and quite expensive. Thus, this project is intended to develop a Finite Element Analysis (FEA) approach as an alternative method in studying the behavior of such connections. The software being used is LUSAS 13.5 and the model used was an extended end plate, welded to the end of a corrugated web beam and then bolted to the column-flange. This type of connection will cause the column to bend about its major axis, and affect the end plate, bolts and corrugated web beam. Therefore, the analysis will be much more difficult as compared to plain web beam. The moment-rotation (M-f) response of the joint was plotted in term of a M-f curve, and then, it was superimposed with the curve taken from an existing experimental result. It was found that the two curves shared the same stiffness at the elastic stage of the loading and they started to diverge as the connection became plastic. However, the LUSAS moment of resistance is 50% more than that obtained in the experiment. Further investigations are necessary to improve the finite element prediction

Through Process Modelling of Welded Aluminium Structures

This thesis aims to evaluate the accuracy, efficiency and robustness of a ‘Through Process Modelling’ concept tailored for analysis of the structural behaviour of welded aluminium structures. In short, the modelling concept relies upon the coupling of a welding simulation tool (WELDSIM), a microstructure model (NaMo) and a non-linear mechanical model (LS-DYNA). An experimental database addressing the capacity and ductility of simple welded joints of 6xxx and 7xxx alloys have been established. The experimental database includes results from studies on butt-welded specimens of aluminium alloy AA6005, AA6060, AA6061, AA7046 and AA7108. Two tempers; T4 and T6 prior to welding were investigated and the subsequent effects of natural ageing (NA) and post weld heat treatment (PWHT) were assessed. Cross-weld tensile tests were carried out with digital image correlation (DIC) to record the inhomogeneous strain field in these specimens. Variations of the mechanical properties of the material in the vicinity of the weld were further studied by hardness measurements. Uniaxial tensile tests were carried out to document and compare properties of unwelded and welded test specimens in the various conditions. Numerical investigations are carried out based on WELDSIM, NaMo and LS-DYNA for the AA6005, AA6060 and AA6061 alloys. The results are compared with the experimental data to identify present capability and limitations of the modelling approach

Moisture Susceptibility Of Superpave Asphalt Mixture With Rubber Polymer Modified Asphalt Binder

Moisture susceptibility or known as stripping are very common road distress in tropical country and it is a safety treat to road users. Polymer modified asphalt binder has been conducted previously to find an alternative material in pavement construction that can be used as new improvement for asphalt mix design. This research was carried out to determine the potential benefits of rubber polymer as modifier to enhance the properties and strength of the bituminous road. In this study, three different types of dense graded Superpave HMA mix were developed consists of unmodified asphalt binder (Control) mix, Rubber Polymer Modified Asphalt binder (RMB) mix and Rubber Polymer Modified Asphalt binder with Hydrated Lime (RMBL) mix. This research evaluates the physical properties and moisture susceptibility performance of dense graded Superpave-designed HMA mix. Laboratory tests, i.e. aggregate testing and Superpave volumetric properties were performed to evaluate the physical properties of these mixtures. The Moisture Susceptibility Test (AASHTO T283) was used to characterize stripping performance of dense graded Superpave HMA mixes. The addition of 4 percent 40-mesh tyre crumbs by weight of asphalt binder into asphalt binder were used to prepare rubber polymer modified asphalt binder. 1 percent Hydrated lime by total weight of aggregate was added into the aggregate to improve the bond between aggregate particles and, thereby mitigating moisture damage. Results from the study revealed that, all the mixes passed the Superpave volumetric properties criteria which indicate that these mixtures were good with respect to durability and flexibility. The addition of rubber polymer significantly enhances the properties of asphalt mixtures. The moisture susceptibility result showed that RMB mix demonstrates better resistance to stripping than those prepared using Control mix. While the addition of hydrated lime as antistripping additive with rubber polymer into bituminous asphalt binder would improve the stripping performance of HMA mixes which indicated that RMBL has the most potential to improve stripping resistance eventually increasing the life span of the pavement and reduce premature pavement failure. Therefore, rubber polymer has high potential recycling market value which can be used as additive to, reduce temperature susceptibility, improve adhesion and cohesion properties and further enhance performance of Superpave designed pavement in tropical climate

International Civil and Infrastructure Engineering Conference 2014

The special focus of this proceedings is to cover the areas of infrastructure engineering and sustainability management. The state-of-the art information in infrastructure and sustainable issues in engineering covers earthquake, bioremediation, synergistic management, timber engineering, flood management and intelligent transport systems. It provides precise information with regards to innovative research development in construction materials and structures in addition to a compilation of interdisciplinary finding combining nano-materials and engineering

Concrete using sawdust as partial replacement of sand : Is it strong and does not endanger health?

This study was conducted to investigate the effectiveness of concrete using sawdust to partially replace the river sand which could reduce both environmental problems and construction cost. In this study, sawdust concrete has been produced where the river sand is replaced with sawdust by 5%, 10% and 15% of the total sand volume. Both wet concrete and hardened concrete (cubes specimens) were tested through material testing and cube testing to obtain the most optimum sawdust concrete design. In addition, specimens have also been tested in environmental laboratory to identify the extent of hazardous use of sawdust to consumer health. This is because the dust used is the waste taken from the unknown root of the level of cleanliness. The result shows that the most optimum design for producing sawdust concrete is that with 10% replacement of river sand. The result is based on the compressive strength obtained. The results of environmental study also show that this sawdust concrete is free from any harmful to health contaminants

Concrete using sawdust as partial replacement of sand : Is it strong and does not endanger health?

This study was conducted to investigate the effectiveness of concrete using sawdust to partially replace the river sand which could reduce both environmental problems and construction cost. In this study, sawdust concrete has been produced where the river sand is replaced with sawdust by 5%, 10% and 15% of the total sand volume. Both wet concrete and hardened concrete (cubes specimens) were tested through material testing and cube testing to obtain the most optimum sawdust concrete design. In addition, specimens have also been tested in environmental laboratory to identify the extent of hazardous use of sawdust to consumer health. This is because the dust used is the waste taken from the unknown root of the level of cleanliness. The result shows that the most optimum design for producing sawdust concrete is that with 10% replacement of river sand. The result is based on the compressive strength obtained. The results of environmental study also show that this sawdust concrete is free from any harmful to health contaminants

Evaluation of cold mix patching materials along Jalan Persiaran Mokhtar Dahari, Selangor

The increasing of road accidents and the economic loss due to maintenance operation is becoming an important issue in Malaysia asphalt industry. Potholes are the most common distress occurred in asphalt pavement which require immediate attention to minimise further pavement damage and reduce the opportunity for potential accidents. Hence, a study was conducted to evaluate the performance of six commercially available cold mix asphalt products in Malaysia. Six kinds of patching materials that is nominated as a company sample A, B, C, D, E and F currently used in practice were tested in the laboratory. The laboratory tests included the sieve analysis, density analysis, bitumen content, volumetric properties and moisture susceptibility test. The result of the laboratory tests indicates that the gradation for all the samples are close to the gradation requirements for the AC14 mix as per JKR Malaysia’s specification. However, none of the samples fully complied with the gradation envelope. For density, all the samples are lower than the requirements for the AC14 mix and none of the samples fully complied with the compaction requirements due to the compaction method using the plate compactor. Meanwhile, for volumetric properties results, stability values of the various cold mix samples met the standard specification. Based on the ranking performance criteria of six different cold mix patching materials, Sample B and Sample D obtained the highest score of compliance with the requirements of the specification