bluuebunny/crossref_metadata_2025_split huggingface dataset:
Shear strength of recycled aggregate concrete beams without shear reinforcement
Authors: Merdas Huda S. , Shallal Muhaned A. 
Published: September 2023

Abstract
Steel fibers have recently become increasingly popular for strengthening reinforced concrete members. This research contains a study of shear strength under the effect of replacing 50% of natural coarse aggregate (gravel) with recycled aggregate (crushed brick) as well as the effect of steel fibers for natural aggregate concrete and recycled aggregate concrete. Five concrete beams with dimensions of 2000 mm in length, 300 mm in depth, and 200 mm in width were tested to evaluate the effect of recycled aggregates and to evaluate the efficiency of steel fibers in improving the shear capabilities of concrete beams. Beams are designed to fail due to shear stresses (without shear strengthening). The specimens were reinforced with four 4" X 16" steel bars at the bottom and two 2" X 10" steel bars as top reinforcement. Three volumetric fractions of steel fibers were used: 0%, 0.5%, and 1%. The samples were subjected to a two-point loading test. The beam samples have a ratio of shear span to effective depth (a/d) equal to 2. The results showed that replacing 50% of natural aggregate with recycled aggregate decreased ultimate shear strength, but adding steel fibers by 1% by volume resulted in an increase of 31.8% in shear strength for a recycled concrete beam. For ordinary concrete, the final shear strength increased by 18.3% and 30.8% when steel fibers were added by 0.5% and 1%, respectively. Moreover, the results also showed that the failure mode of all samples is the shear failure mode.
Repairing and strengthening techniques of RC beams: a review
Authors: Hassan Rafea F. , Latief Ammar Fawzi 
Published: September 2023

Abstract
The purpose of this review is to present the techniques for strengthening or repairing of reinforced concrete-beams (RC). The concrete members, like RC beam are might be required to be strengthened to increase the internal strength capacity to resist additional external loads or repaired to increase the design’s structural rigidity and insulate the reinforcement from aggressive conditions. The experimental studies that related to the techniques of repairing and strengthening of RC beams using: external steel plates, fiber reinforced concrete (FRC), reinforced concrete (RC) jacketing, sprayed fiber reinforced polymer FRP, epoxy injection, mortar jackets, near-surface carbon fiber (SNSM-CFRP) strips, near-surface glass fiber (NSM-GFRP) rods, CFRP laminate and sheet; and adding an ultra high performance concrete (UHPC) layer. All the techniques that were discussed showed that there is an improvement in the general behavior of the beams that have been strengthened and repaired, as well as an increase in the maximum load and ductility.
Review of retrofitting techniques of deteriorated reinforced concrete columns
Authors: Kadhim N J , Al-Ramahee M A 
Published: September 2023

Abstract
To ensure sustainability, all types of building structures should be kept in accepted condition throughout their life of service. Rehabilitation has been the subject of extensive research recently because of rising spending on construction and maintenance of constructed infrastructure. The most recent methods to reinforce current reinforced concrete columns, including both conventional and cutting-edge strengthening procedures, are presented in this study. Frequently, general materials used in repairing on-service reinforced concrete columns are concrete, steel, and different kind of Fiber Reinforced Polymer (FRP) composites. Conventional methods and procedures for different mode of failures strengthening, including all types of FRP procedures Near Surface Mounting (NSM) reinforcement, Externally Bonded (EB) FRP, and textile reinforced concrete will all be included in the discussion, and FRP pre-stressing methods for modifying existing structures.
Behaviour of reinforced concrete corbels strengthened by FRP composites and steel bars: a critical review
Authors: Al-Kaabi Nawras H , Al-Thairy Haitham , Dhaheer M S Abo 
Published: September 2023

Abstract
In reinforced concrete (RC) structures, corbels that extend from the faces of reinforced concrete columns are commonly employed to support primary beams and girders. Frequently, the use of corbels is limited to cantilevers with a shear span-depth ratio that is often less than 2. Because of this relatively low ratio, corbel strength is normally dominated by shear, which is comparable to deep beams. However, owing to some reasons (e.g., design and/or construction faults, modification of facility use, deterioration, and aging), strengthening of existing corbels is becoming of prime importance. The aim of the present paper is to conduct a critical review of commonly proposed techniques that have been implemented to strengthen RC corbels. These techniques comprised near surface mounted (NSM) steel bars, NSM fibre reinforced polymer (FRP) bars, and FRP sheets. The latter strategy included carbon (CFRP) and glass (GFRP) sheets. Hybrid strengthening (combining FRP sheets and FRP/steel bars) was also highlighted in this paper. The strengthened (upgraded) RC corbels were evaluated considering several parameters, including shear span to depth ratio (a/d), quantity and configuration of reinforcement, FRP type, and levels of damage in the tested specimens.
Torsional behaviour of RC beams strengthened by NSM GFRP bars
Authors: Al-Ziady A C , Al-Thairy Haitham 
Published: September 2023

Abstract
Near-surface mounted (NSM) fiber-reinforced polymer (FRP) reinforcement is an innovative, serviceable, and beneficial method for strengthening reinforced concrete (RC) structures. Previous studies have proven that the epoxy-resin bonded NSM FRP method effectively achieved shear and flexural strengthening. However, only a few researches have employed this technique for improving torsion but, no research has been conducted on the use of NSM with GFRP bars and epoxy adhesives. This study investigates the behavior of RC beams subjected to combined torsion when they have been enhanced with NSM GFRP U-shaped and closed stirrups with different overlap sites. Four RC beams with dimensions of (150×250×2000) mm (width X depth X length) were considered in the experimental tests. One RC beam is not strengthened and used as a control beam (CB), while three beams are enhanced with NSM GFRP bars in different shapes and overlap configurations. The findings of the tests in terms of twist angle_applied torque curves, the torque of initial cracking, the ultimate torsional carrying capacity, and the ultimate angle of twist were all recorded and evaluated. It has also been shown that a considerable improvement in the performance of RC beams in twisting can be achieved by using NSM GFRP stirrups. From the different NSM strengthening configurations used in the tests, results have demonstrated that beams strengthened by closed GFRP stirrups at the opposite overlap with 100 cm spacing outperformed other strengthened beams of about 181.5% compared to the CB. In contrast, the beam, strengthened by U-shaped GFRP stirrups with spacing at 200 cm, had the lowest torsional strength of about 48.1% relative to the CB.
Assessing of sustainable construction quality in Iraq under conditions of risk factors
Authors: Abramov I L , Alzaidi Z A 
Published: September 2023

Abstract
The area generally and Iraq specifically suffers in the current period from a lot of political and economic conditions which leads to the emergence of many risk factors and uncertainty in construction projects. In addition to the nature of the climate and the lack of organizational and technical programs and scheduled and continuous preventive maintenance programs in addition to the risks of terrorism and wars. The aim of the study is to assess the extent of the impact of various risk factors on construction facilities and roads for the purpose of increasing the ability of those facilities to confront these risks through managing them and applying selected criteria from the elements of sustainable construction. A questionnaire was prepared to identify the risk factors that may exist in building and construction projects, and after the risk groups were identified through the questionnaire form and personal interviews with the project participants, those groups were analyzed using the structural equation model in the program (PLS -SEM). The results showed that the ecological, economic, political, technical and social risk factors have a clear impact on the quality of sustainable construction of infrastructure projects in Iraq, and thus a clear influence on the project objectives (cost, duration and quality).
The Effect of Using Various Types of Mineral Fillers on Moisture Damage of Hot Mix Asphalt
Authors: Al-Shabani Zainab J. , Obaid Ihsan A. 
Published: September 2023

Abstract
In general, asphalt additives are designed to improve the performance of asphalt mixtures by increasing their durability and resistance to cracking, and other forms of damage. Asphalt additives can be made from natural or synthetic materials, and some are biodegradable. Natural asphalt additives such as steel slag powder and silica fume are generally more sustainable than synthetic ones. The use of sustainable asphalt additives can help reduce the environmental impact of asphalt mixtures while improving their performance. This study aims to evaluate the effects of various fillers on the performance of the asphalt mixture and its tolerance to moisture damage, including steel slag powder, silica fume, and ordinary Portland cement. The research involves establishing a standard reference mix for comparison as well as several asphalt mixtures with varying amounts of mineral fillers (0, 25, 50, and 75% SSP and 3, 6, and 9% SF & OPC). The Marshall stability tests and the indirect tensile strength test were among the tests used to evaluate the mechanical properties, and the results showed that the optimal value for using steel slag powder is (25%) and for silica fume is (9%).
Eco-friendly concrete produced with recycled materials
Authors: Abeer S Z , Hasan Zaid Ali , Karim Abbas Bashar , Hassan Dhay Abdallah , Jabr Dhurgham Naeem 
Published: September 2023

Abstract
Using recycling materials to produce concrete become a major subject for research in the last decades. The work aims to examine the effects of the partial replacement of fine aggregate by recycled rubber. In addition to studying the influence of two different fiber types on mechanical properties of concrete with rubber replacement. Three types of rubbers that differ in particle size are used to find the effect of rubber particle size on compressive strength, splitting tensile strength, and flexure strength of the concrete mix. Two waste fiber types are used which are Rope Waste Fiber (RWF) and Steel Waste Fiber (SWF). The findings showed that minimizing the rubber particle size improved the mechanical properties. Also, using two types of waste fiber (rope and steel) together led to improve compressive strength.
Risk Assessment of the main transport corridor in Iraq
Authors: Shokat Doaa M. , Jameel Abeer Khudhur 
Published: September 2023

Abstract
The increased rate of road fatalities ad injured has been a vital issue. Risk assessment of road project is essential in the planning and design stages to prevent road crashes occurring in the operational stage. In Iraq, the main transport corridor has been designed to connect major cities and used by significant traffic volume which led to increase in the crash fatalities. Therefore, it is important to identify the risk factors and improve the safety level. This paper aims to assess the risk of part of the main transport corridor in Iraq. The selected section is part of Road 9 which connects Abu Gharib district with Fallujah City. The selected methodology of assessment is based on the road features and supported traffic data developed by the International Road Assessment Program (iRAP) agency. The output of the assessment is in terms of star rating and star rating score. Higher star rating means safer road condition while higher star rating score means more dangerous road condition. The results of assessment show high level of risk for vehicles. A set of road improvements that meet safety standards are proposed such as improving delineation, lighting, Metal barriers for the median, central strips, intersection channelization, Various repairs according to the severity of the damage at pavement and using shoulder rumble strips. The results of assessment after improvements show upgrading the star rating to the recommended minimum (3 and 4 stars) for vehicles.
Evaluation of Speed, Flow, and Density Performance under Different Severity of Speed Bumps
Authors: Aboud G M , Khaled T T , Taher E S , Hashim I N , Al-Humeidawi B H 
Published: September 2023

Abstract
Speed bumps are effective traffic calming tools that give transportation experts the ability to regulate vehicle speeds and enhance safety in particular areas. Despite being often utilized in populated areas, they are more common on other, busier roads (especially in developing nations), thanks to their efficiency, low cost of implementation, and simple installation procedure. Numerous speeds, flow, and density relationship hypothesized in various studies are supported by empirical data gathered in favorable circumstances. Because the graph is not a function, those who delved into comparison study under diverse situations frequently employ forced curves to demonstrate how flow and speed are related. However, the research makes an attempt to hypothesize that the behavior of dynamic speed-flow, speed-density, and flow-density functions is identical. In the study, the link between speed and flow under different severity speed bumps. The current study’s main objective is to is to quantify traffic volume and speed according to controlled conditions before comparing them to unfavorable speed bumps conditions of varying severity: low SB1, medium SB2, and high SB3. To determine the link between the traffic characteristics, the Greenshields model is used. The study show that decrease in speed from 66.6 km/h (control section speed) to 39.4 km/h, which is equivalent to a drop in speed of about 40%. SB2’s moderate severity bumps on traffic volume, speed, and density caused the flow rate to drop to 1236 vph and the free flow speed to drop to 28.2 km/h. While SB3’s high intensity bumps had an impact on traffic characteristics, the study show that the maximum value of speed is 5.34 (km/h), which equates to an hourly traffic flow of 816 cars.
Changes in Groundwater Levels and its Salinity (Badra Basin Iraq)
Authors: Rdhewa A M , Karim I , Mohammed Z B 
Published: September 2023

Abstract
A fact that human-induced greenhouse gas emissions have led to an increased frequency and/or intensity of some weather and climate extremes since pre-industrial time, in particular for temperature extremes which affected lots of regions by reducing precipitations. Accordingly, this reduction causes a lowering of groundwater levels which was adopted as a goal of this study and its effects on quality of it. The study area is Badra - Jassan basin located to the north of Kut city, the center of Wasit governorate, and bordered by the international boundary with Iran from the east and northern east covering an area of about (1020) Km2. Badra - Jassan basin is an important hydrogeological basin in which groundwater can be used for agricultural purposes; especially with decreasing surface water supply. The research studied a predictive mathematical model of groundwater by ten wells distributed randomly within the boundaries of the study area; all of them fall within the unconfined aquifer the mathematical model for the study area has been developed using the Geographic Information System (GIS) software. The Groundwater level map for the ten existing wells was drawn from data in (2021) and a comparison with else published in (2002) for the study area. Likewise, the salinity concentration map variations for the same periods were estimated. The present study showed a decline in groundwater levels which conjunction with an Increasing in the range and value of groundwater salinity concentrations.
Electrocoagulation process as an alternative treatment of petroleum industry liquid waste and renewable energy sources
Authors: Pratiwi R , Chusniyah D A , Fajarwati K , Fadliah  , Satiawati L 
Published: September 2023

Abstract
Industrial wastewater treatment technology that is environmentally friendly and renewable energy are two critical issues that have not been resolved. Electrocoagulation technology offers a liquid waste treatment process that simultaneously produces hydrogen gas as a renewable alternative energy source. In this study, an attempt was made to observe the ability of the electrocoagulation process to remove pollutants from the wastewater of the petroleum industry, which is represented by a phenol solution. Meanwhile, electrocoagulation also produces hydrogen gas along the process. Based on observations solution’s pH, voltage and processing time, it was found that the optimal conditions for processing liquid waste containing phenol were obtained by using voltages of 20 volts in a waste solution with a pH 10. The process was carried out within 3 hours. The obtained phenol removed 22 % and hydrogen gas as much as 123.31 mmol/m2 at the end of the process. The development of this process is considered quite intriguing to utilize wastewater treatment as a new renewable energy source.
Application of response surface methodology (rsm) for optimisation of cod removal from tofu wastewater in an adsorption process using silica adsorbent
Authors: Hardyanti N , Susanto H , Budihardjo M A , Purwono Purwono , Saputra A T 
Published: September 2023

AbstractThe entry of pH, turbidity, COD, and TSS pollutants from tofu wastewater decreases discharge water quality and may affect the discharge water treatment process. This study aims to find variations in the mass and size of silica and the optimum adsorption time on the removal efficiency of pH, turbidity, COD, and TSS from tofu wastewater using silica adsorbent with applying surface response methodology. Chemical treatment was carried out to meet turbidity, COD, and TSS parameters. The research method used a laboratory-scale batch system with adsorbent size, mass, and adsorption time variations. From the research conducted, it obtained that the best removal for the pH test was the 100 mesh silica variation in the treatment of 3.295 gr with an adsorption time of 37 minutes; the pH value after removal was 4.87, for the turbidity test was 80 mesh silica variation in the treatment of 10 gr with an adsorption time of 15 minutes and the turbidity value after removal was 114 NTU, for the COD test, the best removal was obtained from a variation of 8.74937 gr of 104,342 mesh size silica at 39.0248 minutes of contact time with a COD value after removal of 851.33 mg/l, then for the TSS test was the 80 mesh silica variation in the treatment of 10 gr with an adsorption time of 59 minutes and the TSS value after removal was 65 mg/l.
Aluminium recovery from aluminium foil waste as coagulant for domestic wastewater treatment
Authors: Mahmudah L , Juliastuti S R 
Published: September 2023

Abstract
The high use of aluminium foil in food and beverage packaging has caused solid waste to increase rapidly, so solid waste treatment is required. This study investigates the best concentration of reactant to aluminium recovery from aluminium foil waste as potash alum coagulant. Potassium hydroxide is used for dissolved aluminium, and sulphuric acid is added to form potash alum crystals. The experimental result got a maximum point for the synthesis of potash alum from aluminium foil: potassium hydroxide 3 M dan sulphuric acid 3 M which produced a potash alum yield’s 99,59% and contains 11,19% of aluminium oxide. The quality of potash alum products is compared to the technical requirements of SNI 0032:2011. Potash alum was applied to the domestic wastewater and compared with commercial alum. The turbidity, TSS, and TDS domestic wastewater treatment results showed that potash alum has better performance than commercial alum.
Development of emission reduction measures of trace gas emissions from coal-fired power plants in Indonesia
Authors: Kusuma S A P , Permadi D A , Dirgawati M 
Published: September 2023

AbstractMost of Indonesia’s electricity demand is supplied by coal fired power plants (CFPPs) which can potentially emit huge amounts of air pollutant gases such as NOxand SO2gas. The country has committed to reduce Greenhouse Gases (GHGs) emission by 2030 through Nationally Determined Contributions but some emission reduction measures may also reduce air pollutant gases. Flue Gas Desulfurization (FGD) and Atmospheric Fluidized Bed Combustion (AFBC) are the leading control technologies for reducing SO2and NOxemissions that can be installed in the CFPPs. This study aims to determine the pollution load of SO2and NOxgases in 2030 generated from CFPPs operation with (reduction scenario) and without FGD and AFCB control technology (business as usual (BAU)). The gas pollution load was calculated using the Atmospheric Brown Clouds- Emissions Inventory Manual (ABC-EIM) procedure. Based on the BAU scenario, the emission load accounted of 1,440,192 tons/year for NOxand 613,121 tons/year for SO2in 2030. After implementing the control technology scenarios in 2030, the NOxemission load is projected to decrease to 579,610 tons/year, and the SO2emission load decrease to 77,920 tons/year. The application of AFBC and FGD control technologies can potentially reduce NOxand SO2emissions load from CFPPs operation in 2030 thus it can help to improve air quality in the future.
Analyzing the performance of cyclones and scrubbers as air pollution control methods for household solid waste incinerator
Authors: Khair H , Nur T B , Suryati I , Utami R , Surya K D 
Published: September 2023

Abstract
Household solid waste processing through incinerators may pose environmental problems, as gas emissions from combustion are released. Air Pollution Control Devices (APCD), such as cyclones and cyclone scrubbers, are frequently utilized to mitigate these issues. This study aims to evaluate the efficacy of cyclones and cyclone scrubbers as APCD for incinerators. To conduct the study, gas emissions for the parameters SO2, NOx, and CO were measured from the combustion of mixed waste in an incinerator with a fixed waste composition. Data were collected every 5 minutes within 45 minutes of combustion at the inlet and outlet of each APCD. The results indicate that using a cyclone can eliminate 37% of NOx and 91% of CO emissions. In contrast, a cyclone scrubber can remove 53% of NOx and 96% of CO emissions. Notably, the gas analyzer failed to recognize the SO2 parameter. Implementing a cyclone can reduce gas emissions from incinerator combustion, and combining a scrubber within the cyclone can increase its effectiveness in reducing these emissions.