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Effect of Construction Joints on Performance of Reinforced Concrete Beams
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Construction joints are stopping places in the process of placing concrete, and they are required because in many structures it is impractical to place concrete in one continuous operation. The amount of concrete that can be placed at one time is governed by the batching and mixing capacity and by the strength of the formwork. A good construction joint should provide adequate flexural and shear continuity through the interface.

In this study, the effect of location of construction joints on the performance of reinforced concrete structural elements is experimentally investigated.

Nineteen beam specimens with dimensions of 200×200×950 mm were tested. The variables investigated are the location of the construction joints (at midspan or at third point of the specimens), type of construction joints (vertical, inclined, and key construction joints), and presence of stirrups at these joints. The specimens were tested using 1000 kN computer controlled versatile electronic testing machine. The specimens were positioned in the machine so that the deflection at center and\or at the location of construction joint was measured at each load step.

The results of the experimental program indicated that the best location of the construction joint is at the point of minimum shear. It was found that the use of vertical construction joint has little effect on the overall behavior of beam specimens (the percentage of reduction in ultimate load capacity is in the range of 0% - 5%).

While inclined construction joints results in a noticeable reduction in strength of beams relative to the strength of beam without construction joint the percentage of reduction in ultimate load capacity is in range of 8% - 20%.The presence of stirrups at the construction joints is an important variable, which affect the type of failure and load carrying capacity. It is found that adding of stirrups across the joint results in an increase in capacity in the range of (7%- 15%) and a decrease in deflection in the range of (20%- 48%).

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Publication Date
Tue Mar 01 2016
Journal Name
Journal Of Engineering
Some Mechanical Properties of Concrete by using Manufactured Blended Cement with Grinded Local Rocks
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The use of blended cement in concrete provides economic, energy savings, and ecological benefits, and also provides. Improvement in the properties of materials incorporating blended cements. The major aim of this investigation is to develop blended cement technology using grinded local rocks . The research includes information on constituent materials, manufacturing processes and performance characteristics of blended cements made with replacement (10 and 20) % of grinded local rocks (limestone, quartzite and porcelinite) from cement. The main conclusion of this study was that all types of manufactured blended cement conformed to the specification according to ASTM C595-12 (chemical and physical requirements). The percentage of the compress

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Publication Date
Fri Jan 01 2016
Journal Name
Journal Of Engineering
Some Properties of Polymer Modified Self-Compacting Concrete Exposed to Kerosene and Gas Oil
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This thesis aims to study the effect of addition polymer materials on mechanical properties of self-compacting concrete, and also to assess the influence of petroleum products (kerosene and gas oil) on mechanical properties of polymer modified self-compacting concrete (PMSCC) after different exposure periods of (30 ,60 ,90 ,and 180 days).

Two type of curing are used; 28 days in water for SCC and 2 days in water followed 26 days in air for PMSCC.

The test results show that the PMSCC (15% P/C ratio) which is exposed to oil products recorded a lower deterioration in compressive strength's values than reference concrete. The percentages of reduction in compressive strength values of PMSCC (15% P/C ratio) was

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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Quality Evaluation of Al-Rasheed Ready Concrete Mixture Plant By Using Six Sigma Approach
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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 f

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Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
The Influence of Alkaline Treatment of Recycled Natural Materials on the Properties of Epoxy Resin Composites
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Natural fibers and particles reinforced composites are being broadly used due to their bio and specific properties such as low density and easy to machine and production with low cost. In this work, water absorption and mechanical properties such as tensile strength, flexural strength and impact strength of recycled jute fibers reinforced epoxy resin were enhanced by treating these fibers with alkaline solution. The recycled jute fibers were treated with different concentration of (NaOH) solution at (25 0C) for a period of (24) hours. From the obtained results, it was found that all these properties are improved when fibers treated with (7.5wt% NaOH) related to untreated fibers. Conversely, the mentioned properties of composit

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Publication Date
Wed Mar 29 2023
Journal Name
Materials
Prediction of the Bending Strength of a Composite Steel Beam–Slab Member Filled with Recycled Concrete
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This study investigated the structural behavior of a beam–slab member fabricated using a steel C-Purlins beam carrying a profile steel sheet slab covered by a dry board sheet filled with recycled aggregate concrete, called a CBPDS member. This concept was developed to reduce the cost and self-weight of the composite beam–slab system; it replaces the hot-rolled steel I-beam with a steel C-Purlins section, which is easier to fabricate and weighs less. For this purpose, six full-scale CBPDS specimens were tested under four-point static bending. This study investigated the effect of using double C-Purlins beams face-to-face as connected or separated sections and the effect of using concrete material that contains different recycled

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Publication Date
Tue Feb 01 2022
Journal Name
Journal Of Engineering
Numerical analysis of a concrete foundation under a combination of a dynamic and a seismic load
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Improving in assembling technology has provided machines of higher evaluation with better resistances and managed behavior. This machinery led to remarkably higher dynamic forces and therefore higher stresses. In this paper, a dynamic investigation of rectangular machine diesel and gas engines foundation at the top surface of one-layer dry sand with various states (i.e., loose, medium and dense) was carried out. The dynamic investigation is performed numerically by utilizing limited component programming, PLAXIS 3D. The soil is accepted as flexible totally plastic material submits to Mohr-Coulomb yield basis. A harmonic load is applied at the foundation with amplitude of 10 kPa at a frequency of (10, 15 and 20) HZ and se

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Publication Date
Tue Nov 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Academic Accreditation From The point Of view The Teaching Staff Of Iraqi Expatriates And Its Impact On Strategic Performance Of Institutions Of Higher Education - Field Research
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Abstract

       The Research Includes Two Variables : First , Academic Accreditation with his dimensions ( Educational Context , Educational Inputs , Educational Process , Educational Outputs , Feedback ) , And The Second : Strategic Performance With His dimensions ( Financing , Satisfaction Stakeholders , Internal Processes , Learning And Growth ) , The Research Highlights On The Academic Accreditation System Which Is Considered A Major And Important Systems Can Through Which Administration Of Activities And Programs Institutions Of Higher Education , As This research aims to determine his relationship And The Extent Of Its Effect In The Strategic Performance , And It Includes The Research C

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Publication Date
Sat Jan 01 2022
Journal Name
Open Engineering
Producing low-cost self-consolidation concrete using sustainable material
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Abstract<p>The disposal of the waste material is the main goal of this investigation by transformation to high-fineness powder and producing self-consolidation concrete (SCC) with less cost and more eco-friendly by reducing the cement weight, taking into consideration the fresh and strength properties. The reference mix design was prepared by adopting the European guide. Five waste materials (clay brick, ceramic, granite tiles, marble tiles, and thermostone blocks) were converted to high-fine particle size distribution and then used as 5, 10, and 15% weight replacements of cement. The improvement in strength properties is more significant when using clay bricks compared to other activated waste </p> ... Show More
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Publication Date
Mon Jan 01 2024
Journal Name
Baghdad Science Journal
On Semigroup Ideals and Right n-Derivation in 3-Prime Near-Rings
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 The current paper studied the concept of right n-derivation satisfying certified conditions on semigroup ideals of near-rings and some related properties. Interesting results have been reached, the most prominent of which are the following: Let M be a 3-prime left near-ring and A_1,A_2,…,A_n are nonzero semigroup ideals of M, if d is a right n-derivation of M satisfies on of the following conditions,
d(u_1,u_2,…,(u_j,v_j ),…,u_n )=0 ∀ 〖 u〗_1 〖ϵA〗_1 ,u_2 〖ϵA〗_2,…,u_j,v_j ϵ A_j,…,〖u_n ϵA〗_u;
d((u_1,v_1 ),(u_2,v_2 ),…,(u_j,v_j ),…,(u_n,v_n ))=0 ∀u_1,v_1 〖ϵA〗_1,u_2,v_2 〖ϵA〗_2,…,u_j,v_j ϵ A_j,…,〖u_n,v_n ϵA〗_u ;
d((u_1,v_1 ),(u_2,v_2 ),…,(u_j,v_j ),…,(u_n,v_n ))=(u_

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Publication Date
Tue Apr 29 2025
Journal Name
Modern Sport
A Comparative Study on the Results of the Administrative Performance Skills Scale Among Heads of Sports Talent Departments in the Ministry of Youth and Sports
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Sports management is a fundamental pillar that supports sports institutions and plays a pivotal role in achieving advanced levels of success in talent development. The Talent Development Project is one of the key strategic initiatives of the Ministry of Youth and Sports. This study compares department heads with effective managerial competence to those with ineffective competence to highlight differences in performance quality. Through this comparison, the urgent need to assess the administrative performance skills of the heads of sports talent departments becomes evident, particularly their ability to lead and manage the Sports Talent Development Project. The objective is to identify strengths and weaknesses, establish a clear framework fo

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