Mohd Zulham Affandi Mohd Zahid

Performance of Concrete by Using Palm Oil Fuel Ash (POFA) as a Cement Replacement Material

Palm Oil Fuel Ash (POFA) is one of the solid waste in Malaysia and had trouble with the ash removal. Therefore, the use of waste oil palm ash can overcome the problem of solid waste. POFA is a pozzolanic material and it can act as a replacement of cement (OPC) to produce concrete with higher strength and low cost. POFA quality will increase as the range made up to a medium level of fineness in the size of 50 microns. POFA used to replace OPC is 0%, 10%, 30% and 50% by weight percent of OPC. POFA concrete compressive strength will be tested after a curing process that concrete age of 7 days and 28 days. POFA concrete density is also tested and compared with OPC concrete. Results showed that compressive strength POFA lower than normal concrete. On the other hand, the replacement of cement by 10% POFA shows a record high in compressive strength compared with other POFA mixing at the age of 7 days and 28 days. Fineness pozzolanic POFA is the best material and can be used as a cement replacement alternative.

UHPFRC as Repair Material for Fire-Damaged Reinforced Concrete Structure – A Review

Exposure of concrete to intense heat will cause deterioration of its strength and durability. Previously, the fire-damaged concrete was repaired using the shotcrete and normal concrete. Recent studies utilize fibre reinforced polymer (FRP) in repairing fire-damaged concrete. Ultra High Performance Fiber Reinforced Concrete (UHPFRC) mostly developed using fine size aggregate, cement, silica fume, super plasticizer and reinforced with steel fibre has an excellent mechanical properties compared to high strength concrete and with an addition of steel fibre in the UHPFRC enhances its ductility behaviour which is not possessed by normal concrete, hence, UHPFRC indicates a promising candidate as repair material to fire-damaged concrete. The aim of this paper is to review on the properties of UHPFRC to be utilized as repair material to fire-damaged concrete structure based on previous research on UHPFRC and fire-damaged structure.

Properties of Cement-Based Material Consisting Shredded Rubber as Drainage Material

Waste tyre caused disposal problem in country all over the world. A lot of research has been done to make use of recycled tyre rubber to minimize waste tyre disposal problem. Recycled tyre rubber has been widely used for civil engineering application such as lightweight concrete and asphalt pavement. However only a few study focused on the development of material using recycled tyre rubber as drainage material for geotechnical purposes. This paper presents the experimental on properties of cement-based material consisting recycled tyre rubber. Specimens were prepared by incorporating different percentage of shredded rubber tyre with mortar. Summation of ten (10) mixes has been investigated to determine the compressive strength, density, porosity and water absorption. From the results, it is concluded that the higher percentage of shredded tyre rubber used, will decreased the compressive strength and increased the porosity and of the material.

Properties of Cement Mortar Consisting Raw Rice Husk

Most of the rice husk is disposed with no further concern and this has caused waste disposal problems. Burning rice husk can cause health and environmental problem. Rice husk ash has been widely used for concrete technology application as additive in concrete mixture. However there is lack of study on the usage of raw rice husk. This paper presents the experimental on the properties of cement mortar consisting raw rice husk which focused on the porosity and density. Specimens were prepared by incorporating different percentage of rice husk with mortar. Summation of 10 mixes has been investigated to determine the compressive strength, density, porosity and water absorption. As the main purpose of the rice husk cement mortar is for drainage material, the main characteristics needed are porosity and lightweight. From the results, it is concluded that the higher percentage of rice husk used, will decreased the compressive strength and density and increased the porosity of rice husk cement mortar.

The Effect of Different Sand Gradation with Ultra High Performance Concrete (UHPC)

Advances in concrete material research has introduced to development the new class of concrete which is known as Ultra High Performance Concrete (UHPC). Due to the most exceedingly awful on nature coarse aggregate quality, UHPC was delivered to success in concrete. This study investigated the effect of differentsand gradation (63-300μm, 300-600μm, 600-1180μm, and normal sand) on compressive strength and ultrasonic pulse velocity (UPV) of UHPC. The rheology of UHPC mixtures was determined by flow test conducted according to ASTM C1611 and the compression testwas performed to measure concrete compression strength at 7 and 28 days according to BS 1881-116 (1983). To determine the quality of concrete, UPV test were conducted according to BS 1881 part 201 (1986).From the experimental results, the results indicated that sand grading with 600-1180μm obtained the highest in compressive strength and UPV.The compressive strength at 28 days achieved 100 MPawith direct transmission of UPV 4.5% higher than semi direct.

Assessment of Reinforced Concrete Building with Soil Structure Interaction Effect under Vertical Earthquake

In past investigation, most of studies on seismic analysis for soil structure interaction effect are small and generally design building were considered to be fixed at their support. In actual condition, flexibility of the bases soil medium were generate some deformation in foundation element and will be shows detrimental effects on the system behavior. This can make a beneficial result on the overall structure response if flexible bases were considered during seismic analysis. The present study attempts to compare the behavior of reinforced concrete medium rise building with soil structure interaction effect and fixed bases under vertical earthquake. The eight-storey irregular 2D frame models were subjected to ground motion from 4 stations with peak ground acceleration ratios vertical to horizontal (V/H) between ranges 0.95 to 1.16. During simulation of simplified model, Impedance Function has been applied to calculate the stiffness of such spring. The structural response quantities were considered displacement histories and axial load variation. The result shows that the consideration of soil structure interaction effect may increase such response behavior.

Behaviour of Axially Loaded Composite Wall Panel by Using Finite Element Analysis

In order to promote the efficient use of composite materials in civil engineering infrastructure, effort is being directed at the development of design criteria for composite structures. Insofar as design with regard to behavior is concerned, it is well known that a key step is to investigate the influence of geometric differences on the non-linear behavior of the panels. One possible approach is to use the validated numerical model based on the non-linear finite element analysis (FEA). The validation of the composite panel’s element using Trim-deck and Span-deck steel sheets under axial load shows that the present results have very good agreement with experimental references. The developed finite element (FE) models are found to reasonably simulate load-displacement response, stress condition, giving percentage of differences below than 15% compared to the experimental values. Trim-deck design provides better axial resistance than Span-deck. More concrete in between due to larger area of contact is the factor that contributes to its resistance.

H2S Emissions within Vicinity of Swine Farming Area in Nibong Tebal, Pulau Pinang, Malaysia

Animal farming industries is important in Malaysia because its contribution to the economy. The production causes all the major environmental negative impact such as water pollution from waste water and malodours emanating from farms. The current methods of disposing of manures were no longer adequate or suitable for the new, large and intensive animal farming. Inappropriate technologies, poor maintenance and inadequate dimensions and design of the treatment systems in addition to inappropriate production method are causing serious environmental problems especially odorous emissions. Present of Hydrogen Sulphide (H2S) in the air contribute to the odour pollution. Static monitoring has been done and maximum concentration of H2S is 220.6 ppb. Temperature and relative humidity fluctuations were seem to have influence on concentration of H2S. Linear regression analysis was shown that relative humidity has higher influence on correlation gaseous pollution compared to temperature. Correlation coefficient for H2S and relative humidity was in range 0.675 to 0.881 in the morning and 0.417 to 0.729 in the evening, which are in range of strong correlations.

Attenuation Function Relationship for Far Field Earthquake Considered by Strike Slip Mechanism

An attenuation relationship for far field earthquakes considered by strike slip has been developed. The attenuation relationship function was develop using regression analysis. The database consisting of more than 130 peak ground accelerations from seven earthquake sources recorded by Seismology Station in Malaysia have been used to develop the relationship. This study aims to investigate the new relationship attenuation to gain exact peak ground acceleration at the location on site. Based on this study, the location is a structure located at Terengganu seaside.

Cross Section Optimization of Plane Truss among Different Spans

Cross sectional areas optimization is to be implemented to study the influence of the cross section shape on the optimum truss weight. By the aid of analysis and design engines with advanced finite element analysis that is the steel design software STAAD. Four rolled steel sections (angle, tube, channel, and pipe) which are used in industrial roof trusses are applied for comparison. Many previous studies, use the areas of cross sections as design variables without highlight to the shape of cross section at the start of the process, consequently the result area will be adequate if the designer choose the effective shape than others. Results of this research show that the chosen cross section shape has a significant impact on the optimum truss weight for same geometry of truss type under the same circumstances of loading and supports.