Preferred Language
Articles
/
joe-2170
Quality Evaluation of Al-Rasheed Ready Concrete Mixture Plant By Using Six Sigma Approach
...Show More Authors

The objective of this research work is to evaluate the quality of central concrete plant of Al-Rasheed Company by using Six Sigma approach which is a measure of quality that strives for near elimination of defects using the statistical methods to improve outputs that are critical to customers. The fundamental objective of Six Sigma methodology is the implementation of a measurement-based strategy that focuses on process improvement and variation reduction to reach delighting customers, and then suggesting an improvement system to improve the production of concrete in Al-Rasheed State Contracting Construction Company.
A field survey includes two parts (open and close questionnaire) that aimed to get the data and information required for achieving the research where the answers of questionnaire sample have led, during the application of DMAIC improvement cycle, to identifying the potential possible reasons that caused quality deviations in concrete works. Two programs have been used: First, ‘Sigma Level Calculator’ which is formulated by the researcher to measure the components of the processes performance. Second, ‘QI Macros Lean Six Sigma SPC Software 2011’ which uses the statistical tools of Six Sigma DMAIC methodology for: identifying the root causes of defects, analyzing the data, determining capability and stability of process. It is concluded that the processes sigma level for the concrete works quality is 2.41 σ and 181,070 DPMO which is considered too bad as compared with the current global competitio

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Aug 01 2015
Journal Name
Journal Of Engineering
Mechanical Properties of High Performance Concrete Containing Waste Plastic as Aggregate
...Show More Authors

         The world's population growth and the increasing demand for new infrastructure facilities and buildings , present us with the vision of a higher resources consumption, specially in the form of more durable concrete such as High Performance Concrete (HPC) . Moreover , the growth of the world pollution by plastic waste has been tremendous. The aim of this research is to investigate the change in mechanical properties of HPC with added waste plastics in concrete. For this purpose 2.5%, 5% and 7.5% in volume of natural fine aggregate in the HPC mixes were replaced by an equal volume of Polyethylene Terephthalate (PET) waste , got by shredded PET bottles. The mechanical propert

... Show More
View Publication Preview PDF
Publication Date
Sun Mar 01 2015
Journal Name
Journal Of Engineering
Retrofitting of Reinforced Concrete Damaged Short Column Exposed to High Temperature
...Show More Authors

Experimental research was carried out to investigate the performance of CFRP wrapping jackets used for retrofitting twelve square reinforced concrete (CR) column specimens damaged by exposure to fire flame, at different temperatures of  300, 500 and 700ºC, except for two specimens that were not burned. The specimens were then loaded axially till failure after gradual or sudden cooling. The specimens were divided into two groups containing two main reinforcement ratios, ρ= 0.0314 and ρ= 0.0542. This was followed by the retrofitting procedure that included wrapping all the specimens with two layers of CFRP fabric sheets. The test results of the retrofitted specimens showed that the fire damaged RC

... Show More
View Publication Preview PDF
Publication Date
Mon Aug 17 2020
Journal Name
International Journal Of Applied Mechanics And Engineering
Analysis of Structural Concrete Bar Members Based on Secant Stiffness Methods
...Show More Authors
Abstract<p>In this paper, the behavior of structural concrete linear bar members was studied using numerical model implemented in a computer program written in MATLAB. The numerical model is based on the modified version of the procedure developed by Oukaili. The model is based on real stress-strain diagrams of concrete and steel and their secant modulus of elasticity at different loading stages. The behavior presented by normal force-axial strain and bending moment-curvature relationships is studied by calculating the secant sectional stiffness of the member. Based on secant methods, this methodology can be easily implemented using an iterative procedure to solve non-linear equations. A compari</p> ... Show More
View Publication
Scopus Crossref
Publication Date
Mon Aug 17 2020
Journal Name
International Journal Of Applied Mechanics And Engineering
Analysis of structural concrete bar members based on secant stiffness methods
...Show More Authors

In this paper, the behavior of structural concrete linear bar members was studied using numerical model implemented in a computer program written in MATLAB. The numerical model is based on the modified version of the procedure developed by Oukaili. The model is based on real stress-strain diagrams of concrete and steel and their secant modulus of elasticity at different loading stages. The behavior presented by normal force-axial strain and bending moment-curvature relationships is studied by calculating the secant sectional stiffness of the member. Based on secant methods, this methodology can be easily implemented using an iterative procedure to solve non-linear equations. A comparison between numerical and experimental data, illustrated

... Show More
Scopus
Publication Date
Thu May 18 2023
Journal Name
Journal Of Engineering
Behaviour of Fire Exposed Reinforced Concrete Rigid Beams with Restrained Ends
...Show More Authors

This paper is devoted to investigate the effect of burning by fire flame on the behavior and load carrying capacity of rectangular reinforced concrete rigid beams. Reduced scale beam models (which are believed to resemble as much as possible field conditions) were suggested. Five end restrained beam specimens were cast and tested. The specimens were subjected to fire flame temperatures ranging from (25-750) ºC at age of 60 days, two temperature levels of 400ºC and 750ºC were chosen with exposure duration of 1.5 hour. The cast rectangular reinforced concretebeam (2250×375×375 mm) (length× width× height respectively) were subjected to fire. Results indicate remarkable reduction in the ultrasonic pulse velocity and rebound number of

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Jan 01 2023
Journal Name
E3s Web Of Conferences
Mitigation of Reflection Cracking in Asphalt Concrete Overlay on Rigid Pavements
...Show More Authors

Reflective cracking is one of the primary forms of deterioration in pavements. It is widespread when Asphalt concrete (AC) overlays are built over a rigid pavement with discontinuities on its surface. Thus, this research work aims to reduce reflection cracks in asphalt concrete overlay on the rigid pavement. Asphalt Concrete (AC) slab specimens were prepared in three thicknesses (4, 5, and 6 cm). All these specimens were by testing machine designed and manufactured at the Engineering Consulting Office of the University of Baghdad to examine for the number of cycles and loads needed to propagate the reflection cracking in the asphalt concert mixture at three temperatures (20, 30, and 30°C). It was noticed that the higher thickness A

... Show More
View Publication
Scopus (1)
Scopus Crossref
Publication Date
Mon Jun 01 2015
Journal Name
Journal Of Engineering
Theoretical Investigations on the Structural Behavior of Biaxial Hollow Concrete Slabs
...Show More Authors

This paper presents a numerical analysis using ANSYS finite element program to simulate the reinforced concrete slabs with spherical voids. Six full-scale one way bubbled slabs of (3000mm) length with rectangular cross-sectional area of (460mm) width and (150mm) depth are tested as simply supported under two-concentrated load. The results of the finite element model are presented and compared with the experimental data of the tested slabs. Material nonlinearities due to cracking and crushing of concrete and yielding of reinforcement are considered. The general behavior of the finite element models represented by the load-deflection curves at midspan, crack pattern, ultimate load, load-concrete strain curves and failure m

... Show More
View Publication Preview PDF
Publication Date
Mon Feb 01 2021
Journal Name
Journal Of Engineering
Assessing the Moisture and Aging Susceptibility of Cold Mix Asphalt Concrete
...Show More Authors

Laboratory experience in Iraq with cold asphalt concrete mixtures is very limited. The design and use of cold mixed asphalt concrete had no technical requirements. In this study, two asphalt concrete mixtures used for the base course were prepared in the laboratory using conventional cold-mixing techniques to test cold asphalt mixture (CAM) against aging and moisture susceptibility. Cold asphalt mixtures specimens have been prepared in the lab with cutback and emulsion binders, different fillers, and curing times. Based on the Marshal test result, the cutback proportion was selected with the filler, also based on the Marshal test emulsion. The first mixture was medium setting cationic emulsion (MSCE) as a binder, hydrate

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Sep 01 2022
Journal Name
Journal Of Engineering
Properties of Roller-Compacted Concrete Pavement Containing Different Waste Material Fillers
...Show More Authors

Waste materials might be utilized in various applications, such as sustainable roller compacted concrete pavements (RCCP), to lessen the negative environmental consequences of construction waste. The impacts of utilizing (brick, thermostone, granite, and ceramic) powders on the mechanical characteristics of RCCP are investigated in this study. To achieve this, the waste materials were crushed, grounded, and blended before being utilized as filler in the RCCP. After the mixes were prepared, compressive strength, splitting tensile strength, flexural strength, water absorption, density, and porosity were all determined. According to the research results, adding some of these powders, mainly brick and granite powder, enhances the mechanical

... Show More
View Publication Preview PDF
Crossref (5)
Crossref
Publication Date
Thu Sep 01 2016
Journal Name
Journal Of Engineering
Response of Laced Reinforced Concrete One Way Slab to Repeated Loading
...Show More Authors

Test results of nine reinforced concrete one way slab with and without lacing reinforcement are reported. The tests were designed to study the effect of the lacing reinforcement on the flexural response of one way slabs. The test parameters were considered is the lacing steel ratios of (0, 0.0025, 0.0045, and 0.0065), flexural steel ratios of (0.0025, 0.0045, and 0.0065) and span to the effective depth ratios of (11, 13, and 16). Two specimens had no lacing reinforcement and the remaining seven specimens had the lacing reinforcement. Four point bending test were carried out, one of the specimens was tested under the static load applied gradually up to failure and the other specimens were tested under repeated load (5 cyc

... Show More
View Publication Preview PDF