bluuebunny/crossref_metadata_2025 huggingface dataset:
Automated technology of forming high-precision aspheric optics for multipurpose optical systems
Authors: Gorshkov V A , Nevrov A S , Smirnova A V
Published: January 2020

The report presents modern manufacturing technology of high-precision optical parts used in optical-electronic systems for various purposes. The report also presents the complex technology of automated shaping (TESAF) of aspherical, including off-axis surfaces of optical elements for optical-electronic systems. In this paper we consider various methods of forming optical parts with virtually any aspherization value and with different values of the off-axis parameter (off-axis aspheric), with the achievement of surface shape accuracy in the limit λ/60 ÷ λ/80 (λ = 0,6328 μm), by the criterion of the standard deviation. Optical systems manufactured by TESAF technology are already being successfully used at present.
Machinability Studies on Abrasive Water Jet Machining of Low Alloy Steel for Different Thickness
Authors: Adam Khan M , Gupta Kapil
Published: January 2020

This paper reports some results of experimental investigation conducted on abrasive water jet machining (AWJM) of medium carbon low alloy (EN24) steel. EN24 steel samples of different thickness have been machined at various combinations of AWJM parameters. Three important AWJM parameters namely water jet pressure, nozzle traverse speed, and stand-off distance have been varied at three levels each. Three important responses i.e. material removal rate, kerf wall inclination, and surface roughness (average roughness) have been considered as the machinability indicators. The variation of these machinability indicators with a range of thicknesses of EN24 steel samples has been investigated. It is found that AWJM is capable to machine EN24 steel at very high MRR even at the increased thickness. But, surface finish deterioration is prominent with sample having higher thickness. Moreover, nozzle traverse speed is identified as the most significant parameter. It is concluded that the jet pressure of 240MPa with traverse speed of 20mm/min can produce good machinability for AWJM of EN24 Steel.
On Productivity of Abrasive Water Jet Machining for Miniature Gear Manufacturing
Authors: Gupta Kapil
Published: January 2020

Quality, productivity, and sustainability are three major indicators to evaluate the performance of any manufacturing process. Abrasive water jet machining (AWJM), which is an advanced or nonconventional machining process possess numerous benefits over conventional and other advanced processes for manufacturing of precision engineering components. Material removal rate directly indicates about the process productivity, and often finds contradictory to quality and sustainability. This paper reports the productivity of AWJM process while manufacturing miniature gears of brass. It is a part of experimental investigation conducted to manufacture high quality miniature brass gears using AWJM process. Taguchi L9 orthogonal array based experimental study where a total of nine experiments with two replicates each was conducted to evaluate the effect of AWJM parameters on miniature gear quality, process productivity and sustainability. AWJM parameters were optimized to enhance material removal rate and an optimum value of 18.80 mm3/min was obtained. Furthermore, AWJM was identified as a superior to conventional machining processes for manufacturing of miniature gears.
Fuel protonation as extra way to improve diesel engine efficiency
Authors: Abdulgazis U A , Savchuk S I
Published: January 2020

This paper presents a method for low-cost protonation (hydrogenation) of diesel fuel. Protonation reduces the estimated fuel consumption to 3.3 g/kWh by intensifying the combustion of diesels, which reduces the external loss of energy due to exhaust gas, as well as the internal losses that occur in the gas-turbine supercharger.
Development of import replacement technology for gunpowder production
Authors: Livshits A B , Pelipenko D V , Staroverov V A , Matukhin E L
Published: January 2020

This article presented the results of the development of new grades of civil gunpowders, not previously produced at "KGTS», and the results of designing of new hunting and sports gunpowder for the shots of 12, 16, 20 shotgun caliber and for the hunting, sports and service rifles, that both presented at domestic and foreign production. Also, there are presented the results of a theoretical and methodological analysis of previous diversification and conversion, taking into account the need for a better solution of import issues and strategy of its implementation in the conditions of existence of external sanctions and restrictions. The market of foreign powders for small arms has been analyzed and foreign gunpowders have been investigated. The positive and negative aspects of the manufacturing technology of foreign powders and the physicochemical and ballistic characteristics of import powders are revealed. Currently relevant is the question of the transformation of the military-industrial complex in accordance with the needs of economic development and national defense of the country. An important emphasis is placed on solving the problems of import substitution and development of export-oriented technology, in particular powder production as a raw material for resourcing and expanding markets of final products sales.
Innovative modernization of production in the conditions of diversification and conversion
Authors: Livshits A B , Pelipenko D V , Yarullin R N , Matukhin E L , Staroverov A V
Published: January 2020

Currently, in the military and defense industries of many countries of the world, there is a tendency to improve the military-industrial potential on the basis of both the creation of fundamentally new special products and military technologies, as well as diversification and conversion of excess and outdated production lines. The situation in the field of armaments became fundamentally new - the lethal force of conventional weapons increased by five orders of magnitude from the beginning of the industrial revolution to the turn of the 21st century. The armed forces gained the opportunity to destroy humanity or to throw it back many centuries ago. As it is known, the beginning of the XXI century anticipates S. Huntington’s forecast that this century will determine the clash of civilizations in the battle for melting world resources, when some civilizations seek to take control of the resources of others, and others to defend their resources. In addition, it is necessary to take into account the latest developments in connection with the suspension and subsequent termination of the treaty signed in 1987 on intermediate and shorter-range missiles. This largely determines the relevance, severity, complexity and scale of the task of modernizing society, the economy and the machine-building complex of Russia.
Research and development of broaching methods on mandrel of large-sized pipe forgings
Authors: Kobelev O A , Albul S V , Kirillova N L
Published: January 2020

In modern day industry of heavy engineering, parts made from billets comprising large-sized pipe forgings are widely used. The paper presents results of the study of various methods of broaching on mandrel of large-sized pipe forgings and presents the results of industrial testing of the developed methods of broaching and designs of mandrels.
Improvement in Thermal Stability of Glass Fiber-reinforced Polyimide Honeycombs
Authors: Korneychuk A N , Bukharov S V , Ivanova S M , Shul G S
Published: January 2020

Results of researches of influence of 1,7-di(oxymethyl) - m-carborane on thermal stability polyimide binding the SP-97K brands are given in article. It is shown that introduction of bis-oxymethyls-carboranes allows to receive more heat-resistant high-coked compositions. The assumption is made that increase in thermal stability happens due to interaction of carborane fragments to oxygen of air and formation of compounds of B2O3 boron oxide.
The idea of complex multi-channel integrated automated system unification for testing structural elements of rocket and space technology made of composite materials into their development and manufacturing technological cycle
Authors: Kulkov A A , Lebedev K N
Published: January 2020

The concept of integration of an integrated multi-channel integrated automated system for testing elements of rocket-space technology made of composite materials into a single information space of the entire enterprise has been developed. When building the architecture of the automation system, the integration of the automated system of technological preparation of tests is provided. A unified mathematical model of the test object, test facility and loading systems, and the collection and pr+ocessing of test results was taken as the basis for modeling the technological process of testing.
Controller settings search area determination in the condition of reduced sensitivity to control object parameters drift
Authors: Livshits M Yu , Pilyugin I A , Ryazantsev P Yu
Published: January 2020

A definition method for the area of controller admissible parameters set-up in an aircraft, machine-building and other industries is offered in this article. Admissible adjustments areas of controller parameters are defined, at which closed control systems have smaller sensitivity to possible deviations of object parameters regulation during their operation. The examples of method applied to automatic control systems of vacuum in the furnace and drum-type boiler flow rate controller are considered.
The increasing of effectiveness of the reinforce holes method for fasteners with composite liners
Authors: Nasonov F A , Zinin A V , Morozov B B , Bukharov S V
Published: January 2020

The bearing capacity of a parts or units with a holes for fasteners and mechanical fasteners depends on the stress-strain state and its accompanying stress concentration in the local area of fasteners. In General, it is influenced by a set of operational and structural and technological factors. To replace the use of metal embedded elements, the technology of unloading the zone of point fastening of joints of composite structures is proposed by creating a combined connection with an intermediate element - a composite liner installed by a thermal compression method along the contour of the hole.
Thermal protection material on the base of silicon-carbide ceramics
Authors: Grinchuk P S , Tretyak M S , Chuprasov V V
Published: January 2020

The results of the thermal tests of silicon carbide ceramics, developed by the authors, intended for prospective use as the outer layer of the combined thermal protection of returnable orbiters and hypersonic aircraft are presented. Tests have shown that the developed silicon carbide ceramics is characterized by high operating temperature (about 2000 °C), resistance to thermal shock (heating rate ~ 65 K/s), and can withstand high thermal loads (~ 7 MW/m2) for a considerable time. Under comparable conditions, the proposed material exceeds by 1.5–2.5 times the WCu pseudo-alloy in terms of the ablation rate of the mass, while it is 5.5 times lighter. Due to the presence of free silicon in the material, the absorption of large heat fluxes can occur due to the melting and evaporation of silicon. This fact has received experimental confirmation. The problem of reducing the catalytic activity of ceramics due to the layer of silicon dioxide formed on its surface is discussed.
Structural analysis and topology design optimization of load bearing elements of aircraft fuselage structure
Authors: Htet Tun Lin
Published: January 2020

Aircraft total weight plays a major role in aircraft design which results in additional payloads and better performance. There are many ways to reduce weight of aircraft structures, for example, using composite materials.Composite materials such as CFRP offer significant weight reduction for aircraft. Weight reduction improves fuel efficiency of the aircraft which results cost of savings. Besides using these light materials structural design optimization is currently a valid methodology which is applied in advanced engineering. Topology optimization is used to yield an optimized shape and material distribution for a set of loads and constraints within a given design space. Whereas this paper deals with topology optimization of fuselage ribs. By using this optimization technique, weight can be reduced 18.36 % of the original weight.
Evaluation of the effect of changing the geometry of the abrasive grains of the grinding wheel on the characteristics of the roughness of the grinded surface
Authors: Bogutsky Vladimir , Shron Leonid , Yagyaev Elmar
Published: January 2020

In the article, based on the analysis of literature sources, the effect of changing the geometric characteristics of abrasive grains during circular grinding on the roughness parameters of the treated surface was evaluated. The proposed dependencies take into account the parameters of processing modes, the size of the abrasive grain and the radius of its rounding, their change during operation, as well as the change in the state of the working surface of the tool, taking into account the processing time. The obtained dependences make it possible to predict the kinetics of changes in the surface roughness in multi-pass grinding.
Effect of Ground Granulated Blast Furnace Slag as Partial Replacement in Fly Ash-Based Geopolymer Concrete
Authors: Abdul Sani M F A , Muhamad R , Mo K H
Published: January 2020

Replacement of Ordinary Portland cement (OPC) with geopolymer concrete (GPC) using fly ash is currently utilized in the construction industry to reduce the excessive carbon footprint. However, fly ash has lower strength development compared to OPC. Due to that reason, ground granulated blast furnace slag (GGBFS) is chosen to be blended with fly ash to produce GPC with improved mechanical strength. The analysis of the mechanical properties includes workability, compressive strength and splitting tensile strength of hardened GPC specimens have been carried out. The specimens were prepared with different percentages of GGBFS, from 0 % up to 20 %, partially replacing the fly ash-based GPC. Experimental results showed that the slump, compressive strength and splitting tensile strength of the GPC increase as the GGBFS percentage increases and found to be suitable for structural application.
Flash Flood Susceptibility Modelling: A Review
Authors: Saleh A , Yuzir A , Abustan I
Published: January 2020

Flash flood is common problem in the developed or developing country especially in urban areas. This is due to the changes of land use, poor planning of drainage system, deforestation and unplanned land use and etc. Flash flood susceptibility modelling (FFSM) for urban area is important to avoid the loss and etc. FFSM can be vital component and essential tools for planning and management of natural disaster and environmental. The objective of this paper is to review selected paper on flash flood susceptibility modelling using Geographic Information System (GIS) coupling empirical models. A lot of methods have been coupling with GIS to developed flood susceptibility modelling, for example, Weight of Evidence, Random Forest, etc. However, there is still lack of susceptibility model for flash flood. The GIS coupling method can improve the accuracy of flood susceptibility modelling. Thus, this paper will review the ability of GIS coupling with empirical models for the flash flood susceptibility modelling.
Exploration on Pavement Surface Conditions Attributed To Mineral Freight and Logistics Operations on Kuantan Road Network
Authors: Ismail A , Intan Suhana M R , Masri K A , Rapar N H
Published: January 2020

The most active mineral mining operations in Malaysia are located in Kuantan, Pahang. The rapid increases of the minerals operations are of concern due to its significant impacts on the environment and human health. While effects to the environment and human health are a great of concern, the effect to the transportation system also should not be neglected. With the continuous growth of these industries, there will be more heavy vehicles generated on road transporting minerals related products leading to several issues especially on road pavement damages. Pavement damages are always associated with its optimum function and may contribute to road crashes. There are several factors that influenced the pavement damages such as weather changes, quality of material use, improper maintenance and traffic operations. This study was conducted to explore the pavement damages occurrence based on traffic operation which focusing on heavy vehicles composition as centre for critical analysis. To achieve this study, the identification of regular routing used for minerals logistic operation from the mining source to the port was chosen as study location. This study was conducted by using visual observation survey and traffic volume survey. A set of historical data on route inspection supplied by Road Care also been used for analysis. Then, data obtained were analyzed using road disability level and road rating assessment. The result shows that the road rating leading to Kuantan Port was less satisfactory (rating C) with the marks of 7.27 and the highest type of damage found was cracking with 36% followed by rutting (33%) and potholes (31%). The outcomes from this study were hoped to bring some understanding on the impact of heavy vehicles towards transportation system within a local road network in Kuantan.
Numerical study of slope protected by rockfill and shredded tyre mixture gabion wall
Authors: Ainul Mardziah A C , Amizatulhani A
Published: January 2020

Abundance of discarded scrap tyre in Malaysia demand diverse recycling products, in order to reduce its environmental pollutions and simultaneously the negative aftermaths to society and future generation. Hence, this paper is established to investigate the potential of tyre derived geo-material as rock fill alternative in conventional gabion type retaining wall, replacing a portion of the non-renewable rock fill. 4-tier scrap tyre gabion wall (STG wall) in terraced position with various scrap tyre ratio from total gabion rock fills volume are modelled to retain a 5.0m height of existing failed slope. The model are analysed by finite element method in Slope/W 2007 software (Morgenstern-Price analysis method) to assess overall stability of the gabion wall and factor safety (FOS) of the treated slope. From this study, higher FOS is acquired when STG wall incorporated into the failed slope compared to using conventional gabion wall.
The Influence of Steel Slag as Alternative Aggregate in Permeable Concrete Pavement
Authors: Nadiatul Adilah A A G , Ayman Mohammed S Y , Ramadhansyah P J , Rokiah O , Hainin M R
Published: January 2020

This study identifies the pervious concrete with a high direct runoff on the pavement incorporating steel slag. This study is progressing in two stages i.e. 1 st stage is obtaining the best mix design by using cubic concrete samples with dimension of 100mm height based on 7 days compressive strength test. Indeed, different proportion of aggregate and ratio were tested in order to select the highest compressive strength which has reached 10.9 MPa in the first 7 days of curing. The cylindrical concrete sample with the dimension of 200 x 100 mm was used in the 2 nd stage. In addition, steel slag was used in the 2 nd stage besides the granite aggregate. In fact, three different percentages of steel slag are involved; 50% Steel Slag and 50% Granite; 30% Steel Slag and 70% Granite; and 70% Steel Slag and 30% Granite. Hydrologically, 13.8 mm/s is the highest Infiltration rate that pervious concrete has reached which has been recorded throughout permeability test. The rainfall intensity which plays an important role on the pavement was identified. Thus, intensity distribution frequency curve was developed using MSMA and compared within filtration rate results of pervious concrete. Mix design ten (M10) has the ability to perform efficiently during highest rainfall intensity meanwhile strength needed to be increased since 10.9 MPa in the first 7 days of curing is not sufficient.
Effect of Defect Width upon Burst Capacity of Composite Repaired Pipe
Authors: Leong K E , Lim K S , Sulaiman A S , Chin S C , Yahaya N
Published: January 2020

In recent years, FRP composite wrap repair is the most preferable pipeline rehabilitation system used in the pipeline industry. However, some issues concerning this repair method are not fully understood by the industry. Effect of defect geometries toward the efficiency of composite repaired pipe is one of the issues that concerned by the industry. Pipeline repair design codes and standards have been developed mainly focus on the defect depth and neglect other defect geometries such as defect length and defect width. Previous studies stated that defect geometries especially defect width should not be ignored in evaluating and designing pipe repair system. Therefore, the burst pressure of the composite repaired pipeline subjected to various defect widths was determined through this study in order to evaluate the effect of defect width upon the burst capacity of composite repaired pipeline. Finite element analysis was used to determine the burst capacity of the composite repaired pipe with rectangular shape of defect. There are three different widths were selected with constant defect length and depth. The base model of composite repaired pipe was developed and validated and then modified with the various defect widths in this study. The result shows that burst pressure for three different models vary with a percentage of 12.51% between the maximum burst pressure and minimum burst pressure. The stress contour plot extracted from the finite element analysis revealed that the area of highest stress (557.7MPa) is located around defect region. As the defect is getting wider and subsequently creating a bigger defect area, stress concentration is also getting larger at the defect region. With this, the composite repaired pipe tends to fail at lower pressure when the defect getting wider. Based on the results, the defect width is proven to affect the burst capacity of composite repaired pipe.
Rainfall Trend Analysis using Box Plot Method: Case Study UMP Campus Gambang and Pekan
Authors: Nadiatul Adilah A A G , Mohamad Zarif M , Mohamad Idris A
Published: January 2020

Climate change leads to changes in precipitation. This phenomenon has already begun to transform rainfall pattern in Malaysia. Rainfall data, temperature data, and evaporation data are collected and recorded monthly to display the relationship between rainfall, temperature, and evaporation to determine the pattern of hydrologic cycle. The relationship obtained, shows weather pattern at campus Universiti Malaysia Pahang (UMP) in Gambang and Pekan. By monitoring of the weather conditions, it can help in controlling the activity in the UMP. Besides, weather data is very important in our life as the rainfall is an important consideration in design runoff conveyance and erosion control. Changing trend in rainfall distribution also gives an effect on hydrological analysis especially related to historical rainfall record. Box-plot method was used to determine the rainfall trend of hydrologic cycle. It is shown that the rainfall data that was collected that the rainfall event differs every year, as an example for 2016, a total of 1982.9 mm was collected and year after it decreased sharply to 994.7 mm in 2017 and for 2018 raised slightly to 1020.9 for UMP Pekan. Whereas for UMP Gambang, 1072.8 mm in 2016, and also decreased slightly to 972.5 mm in 2017 and in 2018 increased to 1309.8 mm. It shows that each year trend of rainfall for each UMP campuses had change.
Nanoparticle in Asphalt Binder: A State-of-The-Art Review
Authors: Ramadhansyah P J , Masri K A , Norhidayah A H , Hainin M R , Muhammad Naqiuddin M W , Haryati Y , Satar M K I M , Juraidah A
Published: January 2020

Increasing traffic volumes and the rising cost of bitumen making it necessary to improve the performance of asphalt binder through bitumen modification. Various types of modifiers have been employed as bitumen binders in order to improve the bitumen mixture, particularly with regard to its resistance to aging, cracks due to fatigue and thermal conditions, moisture-induced damage and permanent deformation. This review study summarizes the performance of nanoparticles as an asphalt modifier. Several relevant literatures were reviewed, which related to the matter associated with nanomaterials such as nano-silica, carbon nano-tubes and nano-titanium dioxide. Recent studies showed that the utilisation of nanoparticle gave great benefits in many ways.For instance, nano kaolin as a mineral clay promises non-hazardous effects to road users. This can result in a healthy environment and help towards increasing the application of green technology road construction.
The Effectiveness of Palm Oil Fuel Ash Cement Paste to Control Degradation in Ammonium Nitrate Solution
Authors: Sadia T , Rahman M E , Raudhah A , Doh S I
Published: January 2020

This paper presents the use of treated palm oil fuel ash (POFA) as a pozzolanic material in modified cement paste to control degradation in ammonium nitrate environment. The POFA used in this study had a mean diameter of 8.7µm. The treated POFA was used to replace cement in different percentage of 0%, 10%, 20% and 30% with a constant water to cement ratio of 0.4. 50mm cement cubes was prepared for mechanical, durability and micro-structural test. Mechanical test consisted of the compression strength test and durability test consisted of the Volume of Permeable Voids Test (VPV). Meanwhile, micro-structural test consisted of the Thermo-gravimetric analysis (TGA). After 28 days of full water curing, the 50mm cubes samples were immersed in 20% ammonium nitrate solution until 90 days. Based on the test results, it was observed that, cement cubes replaced with 20% POFA had good resistance against ammonium nitrate solution. However, in order to improve the current study, a number of recommendations had been suggested.
Factors affecting the success of highway construction projects: the case of Malaysia
Authors: Rahman R A , Radzi A R , Saad M S H , Doh S I
Published: January 2020

Highways are often high-risk projects due to its importance to a nation’s economic, societal, and political development. Therefore, highway projects need to be successful. Numerous researchers have identified the key factors affecting their local highway projects to identify opportunities for improvements. However, the current body of literature lacks that type of information in regards to Malaysia’s construction industry. This study’s objective is to identify factors that are affecting Malaysia’s highway projects from industry practitioners’ perspective. To achieve this objective, interview data with highway project managers are analyzed. Eleven factors affecting the success of highway projects in Malaysia were identified. The factors are: workflow for the design process, competencies of project managers, availability of workforce, availability of materials, availability of equipment, weather, site location, involvement from upper management, support from clients, public acceptance, and efficiency of authorities. This study contributes to the current body of knowledge by providing researchers and practitioners with a set of alternative factors that are affecting highway project success. The lesson of this study would help the industry to promote project success of highway projects in Malaysia.
Short Term Aging Effect of Asphaltic Concrete Incorporating Charcoal Ash from Coconut Shell
Authors: Ramadhansyah P J , Masri K A , Awang H , Satar M K I M , Hainin M R , Norhidayah A H , Mohd Warid M N , Yaacob H , Juraidah A
Published: January 2020

Numerous studies have been conducted to improve the performance of asphalt mixture properties in comparison with conventional mixes. One of the alternatives is utilizing waste agriculture product as additive or replacement into bitumen mixture. Coconut shell is one of the agricultural wastes that can be utilized. This paper aims to study the effect of asphaltic concrete incorporating charcoal ash from a coconut shell under short term aging condition. Charcoal coconut shell ash (CCSA) was added into a bitumen with 0%, 2%, 4%, 6%, and 8% by weight. The original CCSA was initially ground until getting the particles sizes less than 0.075mm. Laboratory simulation of aging was applied in this investigation. Marshall Stability, volumetric properties, resilient modulus, and dynamic creep test were performed to analyses asphalt mixture containing CCSA. It was observed that the addition of CCSA in asphaltic concrete gives the significant development in stability, modulus of resilient and creep stiffness. This study suggests that 4% and 6% of CBA as a supplementary binder could improve the mechanical properties of asphaltic concrete even under aging conditions.
Waste Cooking Oil as Bio Asphalt Binder: A Critical Review
Authors: Ramadhansyah P J , Masri K A , Wan Azahar W N A , Mashros N , Norhidayah A H , Mohd Warid M N , Satar M K I M , Yaacob H
Published: January 2020

The modification of binder with waste cooking oil (WCO) for paving materials indicates the implementation of recycling practice with environmental issues concern, thus improving the proper management of this waste product. This paper presents a critical review of the WCO utilisation as a modifier to enhance binder properties. The review was focuses on the evaluation of WCO in asphalt binder modification and asphaltic concrete mixture. Basically, oil-based modification by using WCO in paving material provides a promising waste material potential in improving the engineering value in terms of rheological and mechanical performance for modified binder and asphalt mixture. It is expected that the addition of this modifier in binder gives superior performance and is comparable with the conventional binder.
Ultimate bearing capacity of peat treated with cement columns in physical model
Authors: Youventharan D , Arif S M , Rokiah O
Published: January 2020

Peat is classified as very soft and problematic soil due to its natural behaviour of high compressibility, low in shear strength and with high natural water content. Cement column method is commonly used to stabilise the soil by improving the engineering properties. This research aimed to study the unconfined compressive shear strength and the ultimate vertical bearing capacity of stabilized tropical peat of East Coast of Peninsular Malaysia. A group of cement columns were tested in a series of physical model testing. To study the strength behaviour of peat with or without the cement stabilization, physical models were prepared with different variables such as; the number of cement column, proportion of binders (Ordinary Portland Cement-OPC) and the pozzolanic materials (Palm Oil Fuel Ash-POFA). In this research, a total of 9 physical models testing of peat soil including one without the stabilized cement column were conducted. A group of 4 and 6 cement columns with 25 mm diameter and 200mm in length each was installed. Samples were cured for 28 days as soon as the mixing of cement columns completed. After curing, a series of axial loads were applied uniformly on the pre-fabricated steel plate footing from the top of the cement column in order to study the ultimate bearing capacity of the stabilised soil. The change in strength of the soil was evaluated using Unconfined Compressive Strength (UCS) test. Based on the results, the highest ultimate bearing capacity was recorded in Model 6 with 6 cement columns with area improvement ratio of 18.83 %. The sample with 300kg/m3 of OPC has the highest UCS value of 106.88kPa. Hence, the cement columns mixed with binder and pozzolanic improved the strength and the ultimate bearing capacity of the peat soil.
Experimental Study on Flexural Behaviour of Reinforced Foamed Concrete Square Hollow Beam
Authors: Othman R , Muthusamy K , Ramadhansyah P J , Youventharan D , Sulaiman M A , Nadiatul Adilah A A G , Chong B W
Published: January 2020

Nowadays construction industry continuously looking for new, better and efficient construction material and method due to environmental impact. This research reported the effect of reinforced foamed concrete square hollow beam in order to reduce the effect of the application of concrete materials. Foamed concrete with density of 1600kg/m³ is now widely used as a structural component like slab and wall due to it lighter than the normal concrete. Meantime, it helps in saving cost and reduce the use of formwork. The hollow section also can reduce the dead loads which contribute to seismic effect in high rise buildings. In addition, the Processed Spent Bleaching Earth (PSBE) is an industry waste which possess a good pozzolanic reaction is used as partial cement replacement in order to make it more environmentally friendly. The experimental program consists of casting and testing of foamed concrete beams of size 150 x 200 x 1500 mm with and without square hollow section. To study the flexural behaviour, all beams are tested after 28 days of curing subjected to four-points bending test in order to analyse the effect of the reinforcement of hollow section on the strength, deflection and mode of failure of foamed concrete beam. The performance of reinforced foamed concrete hollow square beam (RHB) under flexural shows better when compared with conventional solid beam (CSB) and hollow square beam without reinforcement (HB). The RHB exhibited greater strength with lesser deflection and cracking.
Effect of temperatures and loading rates on direct shear strength of asphaltic concrete using layer-parallel direct shear test
Authors: Lung C K , Mohd Hasan M R , Hamzah M O , Sani A , Poovaneshvaran S , Ramadhansyah P J
Published: January 2020

This paper evaluates the influence of temperatures and loading rates on the shear strength of dense asphalt (AC14) prepared based on the Malaysian Public Works Department specification. In this study, different specimen conditioning temperatures, 10°C, 20°C, 30°C, and loading rates of 20.88mm/min, 40.88mm/min, 50.88mm/min, and 60.8mm/min were used to assess the performance of specimens by using Layer-Parallel Direct Shear (LPDS) test. Based on the results, both parameters have significant effects on the shear strength of the asphalt specimens. The results indicate that the loading rate is directly proportional to the shear strength of asphalt specimens. It is because the stiffness of the asphalt mix increases as the loading rate increases. Hence, it enhanced the shear strength of asphalt specimens. On the other hand, the temperature is inversely proportional to the shear strength of asphalt mixes. As the temperature increases, the stiffness of the asphalt mixture reduces due to the lower resilient modulus; therefore, it reduces the shear strength of the specimen.
Finite Element Analysis on the Effect of Hollow Section on the Strength of Foamed Concrete Beam
Authors: Othman R , Muthusamy K , Ramadhansyah P J , Youventharan D , Sulaiman M A , Nadiatul Adilah A A G , Chong B W
Published: January 2020

The environmental impact of cement production has prompted innovative measures to reduce the usage of cement in accordance with the principle of sustainable construction. At the same time, the palm oil industry generates about 2 million tons of spent bleaching earth (SBE) are generated annually with most of it ends up in the landfill, causing environmental degradation. This research focuses on the effect of hollow section on the strength of foamed concrete beam by using processed spent bleaching earth (PSBE) as partial cement replacement. Hollow section of two shapes were implemented at three different locations along the beam specimen. The foamed concrete beams with 30% cement replaced with PSBE were subjected to tensile test at 28 days to observe the effect of hollow section on the maximum load and tensile strength. The deflection of the specimen was compared with theoretical value and the mode of failure was studied. Hollow section of circular and square shape was studied while the locations were on neutral axis, above neutral axis, and below neutral axis. Verification of experiment was conducted using Finite Element Analysis (FEA) software, ANSYS. Test result shows that beams with circular hollow section has higher strength than those with circular hollow sections. The best position of hollow was above the neutral axis as to not impact the weak tensile strength of foamed concrete. FEA analysis shows great accuracy in predicting the performance of the specimens.
Long term effect of strength and durability performance of concrete containing sulphate reduction bacteria under chloride condition
Authors: Irwan J M , Teddy T , Othman N , Khalid F S
Published: January 2020

The chloride ingress in concrete cause deterioration in concrete due reinforcement corrosion. Adding bacteria in concrete can improve material properties and increase durability with mechanism resist chloride ingress in concrete. Chloride ingress in concrete by bacteria is particularly suited for applications in chloride ion penetration in concrete. The research is objective to determine the effect of adding bacteria to the concrete properties. The bacteria used is locally isolated and enriched to suite concrete environment. The type of the bacteria used is identified as Sulphate Reduction Bacteria (SRB). The SRB is added into concrete mix with concentrations of 3%, 5% and 7%. The compressive and water penetration tests at 28th, 56th, 90th, 180th and the 360th day of curing period were conducted. Cubes of size 150mm × 150mm × 150mm were prepared for compressive strength and water penetration tests. The result of compressive strength shows significant strength of 66.3 MPa on the 360 of day. The water depth penetration also shows a significant impact with addition of SRB with 80% reduction of penetrated water into concrete compared to the control specimen. The overall results of bacteria showed promising results and further study on chloride condition capability is encouraging. It can be concluded that SRB with 5% addition was the optimum percentage to obtain the optimum strength and durability performances.
Performance of Modified Mortar Containing Epoxy
Authors: Abdul Latip Arisya , Ali Noorwirdawati , Abdul Hamid Noor Azlina , Salleh Norhafizah , Radziah Abdullah Siti , Shahidan Shahiron
Published: January 2020

Performance of FRP are highly depending on the adhesive used. FRP known to have high specific strength and specific stiffness, high durability against corrosion, light in weight, easy and quick installation therefore reduced manufacture time, great versatility and reduced maintenance. Despite all the the advantages possessed by FRP, there are actually several drawbacks which mainly causes by the epoxy resin. The organic binder are harmful towards humans, expensive and not applicable on wet surface. This study modified and elevated the binder materials by combining different percentage of mortar and epoxy. Compressive strength, density and water absorption of the specimen were tested and the optimum percentage were determined. Epoxy without harderner that were tested in this study is ranging from 0-5 % and composite cement consisted of 50% of Ground Granulated Blast Slag (GGBS) and 50% of Ordinary Portland Cement (OPC). From the experimental results, 3% of epoxy gives promising results as partial replacement of mortar.
Effects of Curing Conditions on Properties of Lightweight Concrete Brick Containing Expanded Polystyrene and Palm Oil Fuel Ash
Authors: Yassin N I M , Adnan S H , Shahidan S , Ayop S S , Kamarulzaman N A , Osman M H , Jamelloddin Z , Majid M , Salleh N , Alisibramulisi A , Wahee Anuar M N A
Published: January 2020

This study presents the effect of curing conditions towards properties of lightweight concrete brick made up of cement, sand and some replacement materials. The replacement materials used in this study is Expanded Polystyrene (EPS) as sand replacement and Palm Oil Fuel Ash (POFA) as cement replacement. The percentage of replacement for POFA is 0%, 10% and 20% whilst 0%, 30% and 50% for EPS. The brick samples have been exposed to different types of curing conditions that is air curing and water curing until the day of test. Among the tests that have been conducted are hardened brick density, compressive strength and water absorption. Based on the findings, it has been proved that the replacement percentage of EPS and POFA has significant impacts towards the brick properties. In addition, it is found that hardened brick density and compressive strength of air curing samples are lower as compared to water curing samples meanwhile the water absorption for air curing samples are higher that water curing samples.
Monitoring Ex Situ Electrokinetic Remediation (EKR) using Nitric Acid as Chelating Agent
Authors: Ayuni S A , Azhar A T S , Azim A , Aziman M
Published: January 2020

Heavy metal has become a serious world crisis due to natural and man-made sources. Zinc contamination in soil is caused by world urbanization and modernization. The Electrokinetic Remediation (EKR) is a green technology aiming at removing zinc contaminated soils. This paper aims to compare the electrokinetic process between Pure System and Nitric acid as chelating agents. The ex situ remediation method using soil box successfully demonstrated that nitric acid which attracted artificial contaminated zinc had been precipitated at the vicinity of cathode terminal in a form of reddish layer. In conclusion, nitric acid is highly recommended as solution for enhancing electroosmosis process.
Development of a Model for OTTV and RTTV based on BIMVPL to Optimize the Envelope Thermal Performance
Authors: Abass F , Ismail L H , Wahab I A , Elgadi A A
Published: January 2020

The thermal performance of a building has a profound effect on sustaining the conditions of indoor environments, and it is critical in obtaining any energy-efficient design. Choosing an appropriate construction material is one of the most effective methods to prevent excessive energy consumption in the building, to minimize heat flows, and sustain a comfortable temperature for occupants. The majority of the existing buildings in Malaysia are mostly constructed using bricks for their outer walls; many studies nominated these materials as the producer of heat. This study is focusing on evaluating the thermal performance of construction materials in a tropical climate, with the involvement of manual calculation methods for Overall Thermal Transfer Value (OTTV) of walls and roof. Therefore, this study proposes integrating Building Information Model (BIM) and visual programming language (VPL) for supporting the calculation of OTTV based on MS1525:2014. The expected result of the proposed system will support designers on calculating OTTV coefficient comparable with the manual calculation, which is considered promising in minimizing time-consuming and human error when optimizing envelope performance during building design. This study proposed a model to access and extract construction materials properties from BIM library using VPL to estimate OTTV value using a real-time calculation tool.
Combining pozzolanic material as ternary binder in Recycled Aggregate Concrete (RAC) to develop a new sustainable concrete
Authors: Tambichik M A , Samad A A A , Mohamad N , Bosro M Z M , Iman M. A.
Published: January 2020

The demand for a sustainable concrete has increasing due to the effect of conventional concrete that led to many environmental problems such as carbon dioxide emission and depletion of natural resources. Hence, this paper discusses about the usage of ternary binder in recycled aggregate concrete (RAC). Ternary binder was developed from combination of palm oil fuel ash (POFA) Class C and rice husk ash (RHA) Class F as partial cement replacement. This study consists of two (2) phases that are; phase 1 to determine the optimum percentage of ternary binder and phase 2 to determine the compressive strength of recycled aggregate concrete with ternary binder system. Compressive test was conducted for 7 and 28 days to determine the compressive strength. The results show that existence of POFA and RHA as pozzolan for ternary binder help to improved strength of RAC. Combinations of 10% POFA + 15% RHA + 20% RA produce a compressive strength up to 32.8 MPa at 28 days. Increasing of RA content up to 20% will reduce the compressive strength. Overall it can be concluded that combination of POFA and RHA as ternary binder in RAC can produce a concrete with satisfactory strength for structural purposed.
Restoration of Aged Bitumen Properties Using Maltenes
Authors: Hussein Z H , Yaacob H , Idham M K , Hassan N A , Choy L J , Jaya R P
Published: January 2020

Reclaimed asphalt pavement (RAP), a material frequently used in asphalt mixtures, is associated with several environmental and economic advantages. Many existing road construction technologies are capitalising on the availability of recycled materials. This study has looked on the usage of maltene as a rejuvenator in aged bitumen. Bitumen with Pen 60-70 was chosen as the control binder. Maltene was added into the aged bitumen at various concentrations (5%, 10%, and 15%) by weight of total binder. The characteristics of rejuvenated bitumen were examined with penetration, softening point, penetration index (PI), viscosity, and storage stability. As the maltene concentration increased, aged bitumen characteristics improved, while the level of stiffness reduced. Mixing temperature and time were significantly linked to the efficiency of blending between aged-virgin binders. Lower mixing temperatures undermined the diffusion of the virgin bitumen into the aged binder, thereby impairing blending efficiency. The results indicate that 15% of maltene can rejuvenate the properties of aged bitumen.
Influence of Dolomite and Granite Waste Content on The Properties of Artificial Marble
Authors: Abdul Samad H , Abd Rashid R
Published: January 2020

The main objective of this work is to characterize and investigate the effect of mineral dolomite and granite waste content on the physical and mechanical properties of artificial marble. Five different samples of artificial marble were prepared with different proportions of fillers. In this study, granite waste is used a filler by substitute the dolomite content from 10 wt% to 40 wt%. Test specimens were evaluated for water absorption analysis, flexural, compression and Barcol hardness properties. It is found that the optimum 10 wt% of granite waste in the composition has increase the flexural and compression strength and reduces the water absorption rate, while the substitution of granite waste does not change significantly the Barcol hardness properties.