Journal of Engineering and Sustainable Development (JEASD)

Compressive strength is deemed to be one of the most paramount of the mechanical properties of concrete. Lately, there is an increase in trend towards a wider use of some alternative materials added to concrete mixture. Also, there are new methods of curing to obtain the early strength of concrete. Although it is known that high temperatures increase the rate of hydration of cement, the influence of this increase on strength development needs further study's. Different curing temperature and curing methods are usually employed to evaluate the compressive of concrete. This research deals with the study of the effect of curing methods and temperature on compressive strength, density, and absorption of two types of concrete. A 216 concrete cube specimens of two different mixes were prepared at w/c ratio of 0.4 and cement content of 380 kg/m3 for the reference concrete mix which is designed according to the ACI 211-1. Second mix was prepared with 4% cement replacement with silica fume by weight. The samples were submerged by water with different curing temperature (20, 40, 60, and 80) °C for 3 hours. After samples cooling, the cubes were divided into three groups (water submerge curing at 20°C, sealed by polyethylene bags curing, and air curing) until testing ages of (7, 14, 28, 90) days. The results showed that water submerge curing method had the highest compressive strength, density, and lowest absorption followed by the sealed curing.

In this research the induction heating (IH) furnace is simulated and analyzed to implement brazing process using two programs to couple the electromagnetic and thermal analyses, Ansoft Maxwell and ANSYS packages. The simulation by Ansoft Maxwell package is used to determine the electromagnetic field distribution inside the work coil and calculate the Ohmic loss for three different excitation currents (100A, 200A and 300A) and different frequencies (50 kHz, 75 kHz and 100 kHz). The simulation by ANSYS package is used to determine the temperature distribution inside the workpiece and the required work coil current and its frequency to raise the temperature of the two Copper workpieces up to 1000 (below melting point (1083 )) within two minutes only. The simulation results are well matched with the practical brazing process done in the lab.

The main objective of the research is to highlight the extent of considering environmental impacts of building materials when making choices about the selection of building materials. The research object was achieved through two stages, the first stage included a theoretical study to identify environmental impacts of buildings construction and the importance of building materials for a construction project, while the second stage included a practical study to collect the necessary data and information to realize the reality of the process of selecting building materials for buildings construction. The practical study included personal interviews with engineers that have experience in buildings design, and then a closed questionnaire was conducted in order to achieve research object. (45) Questionnaire forms were distributed. the results showed a clear interest from the research sample in the importance of considering environmental impacts when selecting building materials as well as a clear weakness in the application of it on the ground because of the absence of instructions and motivating factors on one hand and the absence of data concerning environmental impacts of building materials on the other hand.

In this paper, an experimental study has been conducted to investigate the behavior of composite concrete beams damaged and cracked under pure torsion , and then repaired by external strengthening with high strength CFRP(Carbon Fiber Reinforced Polymer) laminates bonded with epoxy after doing all the appropriate preparations for the concrete adhesion substrate. Four composite modify reactive powder concrete (MRPC) I- beams,1300mm length,100mm web width and 320mm height, with different type of section (Solid & with opening) were tested to obtain the effect of amount of CFRP laminate on beams cracking torque behavior, angle of twist and failure modes. The results obtained from the adopted repairing technique showed a significant effect of external high strength CFRP laminates on effectively restore of section solid the range of 84% to 85.33% of crack torsional strength effectively restore. As well as the results show that effectively restore of section opening by 80%- 82.22% of crack torsional strength.

Due to the current popularity of reinforced concrete (RC) wall construction, and the new published of codes of concrete, RC walls have become just as an important structural elements as beam, slabs and columns. This paper presents an experimental study of structural behavior of thin concrete wall panels subjected to axial eccentric uniformly distributed loading with varying aspect ratio (AR=H/L) and concrete type (concrete strength (f'c)). The experimental program included testing of six two-way thin concrete wall panels, fixed at all sides and applying the load axially with eccentricity equal to wall thickness/6).The results indicate that the load carrying capacity of the normal strength concrete (NSC) wall panels decreased with the increase in AR (H/L) from 1.25 to 2.00, the ultimate load reduced from 37.5% to 14.6 % when AR decreased from 2.00 to 1.25. For Reactive Powder Concrete (RPC), the ultimate load reduced from 38.7% to 16% when AR decreased from 2.00 to 1.25. The strength of the concrete wall increases with the increase in concrete strength (f 'c) from 33.5MPa to 120.4MPa , the increase is about (212.5, 207.3, 206.67) % for panels with H/L = (1.25, 1.50, 2.00) respectively.

This paper present a method for hand gesture recognition through Statistic hand gesture which is namely, a subset of American Sign Language (ASL). The proposed technique presents an image of hand gesture by passing it through four stages, preprocessing, normalization, feature extraction, and classification. The wavelet neural network is used to build information models because it can handle very complex interactions. The practical system is simulated using MATLAB. The performance of suggested method is excellent compared with traditional approaches and the final results of selected patterns recognition are powerful.

The main goal of steganography is to hide the existence of any secret data from the eye of third
party, so the resultant stego-image must appear normal and not suspicious after the impeding process.
Stego-image must have an acceptable quality in comparison with its size. Moreover, its size has to be on
the rate of the usual Internet images, because it is required to be sent by this medium. This work focuses on
these problems, using a novel Selected Least Significant Bit method. Standard color images were used to
hide the data. The proposed approach has been evaluated and the results had been analyzed. The obtained
results showed clear enhancements on the impeding space considering previous related works.

The purpose of this paper is to establish a finite element model using ANSYS computer program version 15 that is capable of interpreting the use of internal hybrid reinforcement (consisting of combined CFRP bars and ordinary steel bars) in concrete corbels as well as the possible use of CFRP sheets for strengthening these corbels externally. It is aimed from such analysis to create small size corbels that are capable of resisting higher ultimate loads compared with ordinary R.C corbels. The validity of the proposed F.E model is checked by comparison with previous experimental results which exist for two separate cases. Namely the case of concrete corbels with internal hybrid bars but no external CFRP sheets; and the case of external CFRP sheets but no internal CFRP bars. The proposed F.E model having been verified through close agreement with the results of the existing experimental tests, it is then used to provide new data for estimating the ultimate capacity of concrete corbels containing both hybrid bars as well as external CFRP sheets. It is found that the ultimate strength of concrete corbels can be enhanced by 50% when both CFRP bars and CFRP sheets are used together in the corbels, and that only 30% strength enhancement can be obtained if CFRP bars or CFRP sheets are used separately.

: One of the most effective methods used in the biological treatment of a wastewater is the activated sludge process. The importance of the biological kinetic parameters determination is clearly illustrated by the fact that it is usually used in designing such systems. The present study aims to depict the problems faced during the experimental work of determining the bio-kinetics and their causes with an attempt to find proper solutions for them. A completely mixed continuous flow bench scale reactor was operated to determine the biological kinetic for municipal wastewater, during which the generated problems were depicted and solved. It was found that the most common affecting problems were sludge bulking in the final clarifier, followed by rising sludge, filamentous bacteria, settlement of biomass at the bottom of the aeration tank, and finally low biomass activity either immediately after acclimation or after steady state was reached. Solutions were recommended for each problem having continuous monitoring of several parameters at the reactor as their base. Despite the fact that different problems and their solutions have been introduced in this paper, there is no guarantee that all problems are covered. However, one can benefit from what is available.

An Innovative technology is used to recover some of the thermal energy of wastewater released by washing section in a restaurant as one of the energy saving applications to reduce electrical energy consumption for heating, as well as saving money. This research suggests using heat exchanger to recover heat from the sewage hot water (about 45oC) to reheat the dining room for a proposed restaurant, and this will supply up to 8 Tons of heating load and will reduce the electrical energy that used to heat the place up to 44%. This technology within the system routes the passive energy conservation and considers another step on the way of sustainability.

A nonlinear finite element analysis carried out to investigate the behavior of a simply supported reinforced concrete deep beams to study their shear behavior after being strengthened by externally bonded carbon fiber composites materials (CFRP). Seven identical porcelanite lightweight aggregate concrete deep beams were analyzed numerically by using ANSYS computer program, two of them were unstrenghtened to serve as reference beams while the remaining five were strengthened using carbon fiber strips in different orientations (vertical, horizontal and inclined) and different number of layers (one and two layers). The locally available natural porcelanite aggregate (from western region of Iraq) was used to produce a structural lightweight aggregate concrete. Two different values of the shear span to depth ratio were adopted. The finite element analysis covers load-midspan deflection behavior, first shear crack and ultimate loads, and the crack pattern of the tested deep beams. Good agreement is obtained with available results which indicate the efficiency of the finite element method used to model the problem.

An obvious shortage appears in local market of security system especially glass-break system. A trial to construct a primary prototype of glass-break system capable to expand to other tasks is attended. Like using variation in apparent distance that measured by Ultrasonic device as a way to estimate temperature of the room. Arduino Uno microcontroller using Ultrasonic sensor with mobile phone to communicate to a predefined phone number for alarm is constructed and tested with the aid of Lab Top computer using USB interface.

Multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) is a powerful technique to increase the capacity of wireless communication system and decrease the effect of selective fading to flat fading channel. In this paper 2×2 MIMO-OFDM system is implemented using Xilinx system generator (XSG). Simple MMSE equalizer is implemented at the receiver to detect the signal over MIMO channel. The following features are implemented and added to the proposed system: increasing security of the system using chaos based scrambling, using 16-ADQAM modulation to solve the ambiguity problem and implement FFT in pipelining method. The results show that the original data is recovered successfully at the receiver. The VHDL code file is generated for this system for Xilinx Virtex-4 device for hardware implementation purposes. The system is routed in successfully using ISE 14.1 program with resources of 21% slices Flip Flop, 57% LUT, 71% occupied slices and 87% DSP 48s numbers from the selected device. The Xilinx system generator is more flexible, easier, and reliable and gives optimum design for FPGA technique comparing with conventional FPGA design.

: One of today’s most important societal concepts is sustainability. This ideal can be described as meeting the needs of the present without compromising the ability of future generations to meet their own needs. Hot mix asphalt (HMA) recycling produces an eco-friendly mixture known as Reclaimed Asphalt Pavement (RAP). The main objective of this paper is to determine the effect of RAP percentage usage on the characteristics and properties of asphalt concrete mixtures. In this paper, a detailed laboratory study is carried out by preparing asphalt mixtures specimens using aggregate from Al-Nibaay quarry, (40-50) grade asphalt from dourah refinery and four different percentages of RAP material: 0%, 5%, 10%, and 15%. The experimental testing program included four point repeated load and Indirect Tensile Strength tests. The experimental results indicate that, that the inclusion of RAP materials improves fatigue properties of HMA mixtures; fatigue life (Nf (at RAP content of (15 %) increases by (157.1%), (100%), and (150%) at testing temperature 25, 10, and 40°C respectively. Based on the modified Lottman test, it was found that HMA with RAP additive had a high resistance to moisture damage through increasing the indirect tensile strength of such mixtures. The results of four point repeated load test and IDT test indicate that the amount of new binder that needs to be added to the RAP mixture can be reduced without significant effects on the quality of the produced mix.

The type of works in construction companies and projects imposes dealing with large and complicated amount of documentation and information due to the multi processes and stakeholders involved in construction companies and projects. The processes of documentation, exchanging information, and updating these documentation and information became management challenges. This
study aims to investigate the existence of the problems which related with documentation, updating information and following up construction project in Iraq. These problems could be summarized with the following shortcuts: Exchanging information, Updating Documents, Profitability and productivity, Working Efficiency, Competitiveness Requirements, keeping Up to date with Changes, Information Access, Recording Delay and Resources Allocation. Based on the related previous studies, the researcher detected the research questions to build the questionnaire form. Five scales of answer options have been adopted in the questionnaire form. The research population of this study is the team parties involved in the construction works of the companies and projects. 150 questionnaire forms have been distributed, but only 80 forms are collected. Accordingly, the responding rate is about 53%. The findings of this study revealed that the problems which related with Exchanging Information, Updating Documents, Profitability and productivity, and Working Efficiency exist, but a company sometimes faces it. The problem of Competitiveness Requirements exists and a company always suffers from it. The problems of keeping Up to date with Changes, Information Access, Recording Delay and Resources Allocation exist and most of the companies sometimes safer..

This study is part of the studies, conducted her study tested the Faculty of Engineering, University of Mustansiriya to investigate the behavior of reinforced concrete inverted hollow core dapped end beams under effect of static loads. Seven specimens with dimension (length 1220 x height 240 x width 130mm) with different section (i.e. without or with hollow core) and simply supports under concentrated load applied at two points. The main variable are section type (with or without hollow core), hollow core location (top or bottom fibers of beams) and the beam strengthened or unstrengthen with longitudinal normal bars (bolts of diameter 12.5 mm) work as installed after casting normal bars installing after finish curing of specimens at top fibers. Comparison between specimens are based on load carrying capacity, contrast deflection, load-deflection curves, crack patterns and modes of failures for all beams. Results show after test till failure the recess provided by PVC pipe (diameter of 50mm and length 500 mm) led to decreased in load capacity by about (6.5-9%) and give increase in deflections by about (33- 35%) compare with solid beams section. The longitudinal normal strand bars used in strengthened led to increase in load carrying capacity and decrease in corresponding deflection compared with other unstrengthened beams by about (6-21%) & (13-29%). Also increasing strengthen ratio by longitudinal bars (bolts) to twice gives gain in strength capacity and by about (4-9%) for different case of recess location (top or bottom fibers).

The engineering nature of construction project imposed managers lay down proper planning to control activities and takes throughout the project, so the planning in considered as abasic subject for construction companies to control time, cost and quality of products and to maintain competitive postion in construction market and to address this challenges requires the project management methods in this area and the potential of a smart and distinvtive in making the right decisions. The method of multiple criteria complex propprtional assessment of alternatives with Grey relations (COPRAS-G) is one of those methods. This research focuses on providing (COPRAS-G)technique helps to make the best decisions when setting up the project, which encountered problems are complex and multi- criteria (MCDM). And apply this technique on avariety of area as it allows the comprehensive study and non-biase criteria and alternative. This research aims to higlight the importance of planning the development of construction projects and how it can be employed technical grounds (COPRAS-G) in assessing development planning in construction contract companies in iraq through the identification of the criteria used to select the best company in terms of planning the development of construction projects and also to identify alist of contruction companies in Iraq in order to choose the company optimization of this area. For the purpose of achieving the objective of research has been collecting it own data from the literature that dealt with multiple criteria ....