Open Engineering最新文献

{"title":"Research on dynamical properties of a three-wheeled electric vehicle from the point of view of driving safety","authors":"M. Blatnický, J. Dižo, Andrej Suchánek, P. Šťastniak","doi":"10.1515/eng-2022-0441","DOIUrl":"https://doi.org/10.1515/eng-2022-0441","url":null,"abstract":"Abstract Many vehicles in urban and suburban environment are occupied just by one passenger, i.e. by a driver. Therefore, it is worth to think about vehicles, which would be smaller and lighter and which would include environmental-friendly power source. One such vehicle is the presented three-wheeled electric vehicle. This vehicle is designed for one passenger and it is powered by an ecologic electric powertrain. Therefore, it is necessary to research its driving properties. There are two types of vehicle designs, an original design and a modified design with a reworked body. Both are characterised by the symmetrical distribution of the mass to the longitudinal axis. In terms of driving properties of the vehicle, overturning stability during cornering and vertical dynamics in terms of safety are assessed for both original and modified designs. The article presents the main description of the original and modified designs of the three-wheeled vehicle and results from simulation computations focused on analysis of the over-turning stability. It has been revealed that the original vehicle, which is lighter, has better dynamical properties in curves with regards to driving and the higher total weight of the modified vehicle is safer in terms of vertical dynamics.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49542938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seismic evaluation cylindrical concrete shells","authors":"A. M. Hammood, David A. M. Jawad","doi":"10.1515/eng-2022-0417","DOIUrl":"https://doi.org/10.1515/eng-2022-0417","url":null,"abstract":"Abstract The reasons for concrete roof shells’ apparent seismic resistance have been subject to limited research but they have been shown to be inherently resilient to earthquakes. Shells constructed of concrete exhibit high structural efficiency and can therefore be made very thin. As a result of their relatively lightweight nature, thin shell structures are implicitly resistant to earthquake forces. The shell structure is typically designed so that it performs optimally under gravity loads, which are carried mainly by membrane action over the shell surface. As earthquakes induce unexpected horizontal forces, concrete shell structures can be damaged by bending stresses. By studying 8 cm-thick concrete roof shells using parametric analysis, this research shows that small and midsized (span <30 m) thin concrete roof shells can indeed be intrinsically earthquake resistant. These structures have high geometric stiffness and low mass, which results in fundamental frequencies far higher than those of realistic seismic events. Under earthquake excitation, these characteristics result in elastic shell behavior, without exceeding the maximum concrete strength. A shallow shell exhibits greater stress in response to earthquake vibrations caused by the vertical components than by horizontal components. Further, by increasing the rise and curvature of large shells, the fundamental frequency increases and the damaging effect of vertical earthquake vibration is reduced. The aim of this study in general is to show the analysis and the effect of earthquakes on cylindrical concrete shells.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49614557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and numerical evaluation of tire rubber powder effectiveness for reducing seepage rate in earth dams","authors":"Zahraa Khalid Shuhaib, S. Khassaf","doi":"10.1515/eng-2022-0422","DOIUrl":"https://doi.org/10.1515/eng-2022-0422","url":null,"abstract":"Abstract Tires waste is an undesirable urban industry surplus that has grown worldwide yearly. Because of its seals, this material may be used in earth dams, one option for disposing of this waste. Since this is the main objective of this study, an experiment on a soil sample with various ratios of rubber powder has been conducted to better comprehend the impact of tire rubber powder (TRP) on the seepage rate in earthen dams. This study used physical and numerical models to investigate seepage through earth dams. Analysis indicates that the plotted seepage line in SEEP/W software was comparable to the observed seepage line in the physical model. TRP was tested at concentrations of 15, 30, and 50%. The research demonstrates that there has been a noticeable improvement in reducing the seepage rate through the dam’s body; seepage was decreased by 11.28% when a 15% ratio was adopted, a far smaller impact than the other percentages. The proportion was consequently raised to 30%. The seepage rate was found to be reduced by 35.6%, and TRP with a 50% ratio showed excellent behavior in lowering the water level (phreatic line) from the core point to the downstream face D/S and reducing the seepage rate by 41.5%, producing significantly better results. The findings in SEEP/W software indicate that the relative error in seepage rate varies, averaging 11.8% for the first model, 12.18% for the second, 1.65% for the third, and 7.63% for the fourth. The first and second physical models’ seepage rate (relative inaccuracy) dramatically increased as a result of the presence of piping.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46080129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A case study of T-beams with hybrid section shear characteristics of reactive powder concrete","authors":"R. Atea, Rasha A. Aljazaari, Hasanain M. Dheyab","doi":"10.1515/eng-2022-0424","DOIUrl":"https://doi.org/10.1515/eng-2022-0424","url":null,"abstract":"Abstract As an extension of recent developments in concrete understanding, an extensive study is currently being conducted on the structural performance of reactive powder concrete (RPC). This article guides how to investigate the shear behavior of RPC T-beams and calculate their ultimate and breaking shear capacities. The mechanical features of this construction material and approach to revising the reactive powder shear hybrid segment T-beams are cast-off in this motion and are investigated in this experimental study. To evaluate the effects of volumetric ratio of steel fibers, silica fume ratio, and tensile steel ratio, introductory section on the effectiveness of T-beam shearing reactive powder, the program of experimentation involved trying four beams. The research aimed to determine the deflection conduct of the load, downtime approach, strain amount over the beams’ depth, and failure form of cracks. In examining reaction powder’s mechanical characteristics mixtures, steel fiber volumetric ratio and silica fume volumetric ratio were also studied. Furthermore, a hybrid beam study revealed that by using reactive powder web and regular concrete in flange effectively, T-beam concert is enhanced when associated with normal concrete T-beams by 12%. Hybrid beams have also revealed that using reactive powder flange and usual concrete in a web effectively advances the show of T-beams when associated with standard concrete T-beams by 28%.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45638269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural behavior of concrete filled double-skin PVC tubular columns confined by plain PVC sockets","authors":"J. L. Abbas","doi":"10.1515/eng-2022-0404","DOIUrl":"https://doi.org/10.1515/eng-2022-0404","url":null,"abstract":"Abstract The behavior of concrete-filled double-skin poly vinyl chloride (PVC) tubular columns confined by plain PVC sockets is studied in this research. The plastic pipes have been used with concrete as columns. PVC has several advantages as it is inexpensive, light weight for construction, and decrease in the time taken for construction. Thus it can be used as an alternative to metal in various applications in which the maintenance cost is increased and the corrosion is reduced. This study is an experimental work on four groups of composite hollow PVC columns, each group containing three different samples. The effects of several parameters are studied, including slenderness ratio, compactness ratio, compressive strength, and confinement ratio. The experimental results show that stiffness, strength, as well as the ductility of composite columns of different loadings were considerably influenced by all these parameters. An increase in loading carrying capacity by about 40.4% was noticed as slenderness ratio decreased from 20 to 12 and about 21.1% as compactness ratio decreased from 50 to 25. Besides, the rate of increase in load capacity was about 96.6% as compressive strength increased from 33 to 54 MPa. For the case of variation of confinement ratio from 25 to 75%, the increase in the axial load capacity was about 56.7%. The main benefit of this type of column is the interaction between PVC tube and concrete. Besides, restriction of concrete by tube results in the delay of local buckling so that the concrete strength is enlarged by the effect of confining provided by the tube.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42054564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of openings on simply supported reinforced concrete skew slabs using finite element method","authors":"Kaythar A. Ibrahim, S. Al-Darzi, M. H. Shukur","doi":"10.1515/eng-2022-0464","DOIUrl":"https://doi.org/10.1515/eng-2022-0464","url":null,"abstract":"Abstract Reinforced concrete skew slabs are commonly used in bridges due to space constraints in motorways and in congested urban areas. Such slabs also often need to contain openings for architectural requirements or services, and this study seeks to determine the effect of these openings on the strength of the skew slabs. The finite element method was used to analyze 13 cases of slabs with skew angles of 45°. The first and second cases were used to validate the results with experimental work. Other cases studied the effect of the position and shape of openings on the strength of the skew slabs under both one-point and four-point loading conditions. The study also showed that the worst location for the opening was near the obtuse corners since this is where most of the load is transferred. With respect to the shape of openings, three different shapes with the same area were used: skew, circle, and square shapes. It was found that the effect of the opening shape depends on how many steel reinforcements are removed, as well as the appearance of negative cracking brought on as a result of the opening. Overall, the square shape introduces the smallest reduction in the skew slab strength compared with a slab with no opening. Accordingly, the study recommends that the strength of skew slabs can best be maintained if square openings are employed near the acute corners, alongside negative steel reinforcement to avoid cracking.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47455753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of nano chromium addition on the corrosion and erosion–corrosion behavior of cupronickel 70/30 alloy in seawater","authors":"Ayad Mohammed Nattah, Asia Mishaal Salim, Nawal Mohammed Dawood","doi":"10.1515/eng-2022-0491","DOIUrl":"https://doi.org/10.1515/eng-2022-0491","url":null,"abstract":"Abstract Cupronickel alloys have found widespread use in various applications such as heat exchangers, refrigeration systems, equipment, pumps, and pipes. However, the inherent structure of cupronickel alone may not be able to withstand certain aggressive environments effectively. To address this issue, the mechanical properties and corrosion resistance of cupronickel alloys can be enhanced by carefully selecting the appropriate alloying compositions. The addition of nano chromium (20 nm) has been proposed as a means of designing cupronickel alloys with improved performance. In the present study, corrosion and erosion–corrosion behaviors of cupronickel 70/30 alloys produced by the casting method without and with three different additions of nano Cr (1, 1.2, and 1.5 wt%) were investigated. The prepared specimens were subjected to electrochemical tests in 3.5 wt% sodium chloride solutions to evaluate their corrosion behavior. Additionally, an erosion–corrosion test was conducted at an impact angle of 90°, using a slurry solution containing 1 wt% SiO 2 sand in 3.5 wt% NaCl solution as the erodent. The specimens were comprehensively characterized using scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction techniques. The surfaces of the alloy specimens exhibited superficial attacks, but no pits were observed. Moreover, the surfaces developed a greenish coloration. The electrochemical tests conducted using saline solution revealed that the corrosivity of the cupronickel alloy with nano chromium addition varied from moderate to low, depending on the selected concentration. Despite undergoing corrosion in the saline environment, the modified cupronickel alloys demonstrated good resistance to this corrosive process. Therefore, they can be considered suitable for use in highly aggressive environments, such as in seawater capture systems. The erosion–corrosion test results indicated that the addition of nano chromium significantly enhanced the resistance of the specimens to erosion–corrosion. At 1.5 wt% Cr, the erosion–corrosion rate was reduced by 99.27%.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":"239 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135212044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation method of corrosion current density of RC elements","authors":"Faustyn Recha","doi":"10.1515/eng-2022-0430","DOIUrl":"https://doi.org/10.1515/eng-2022-0430","url":null,"abstract":"Abstract The work is theoretical with the use of analytical calculations, subsequently confirmed by a numerical method, in which an attempt was made to verify the method of estimating the corrosion current density based on the deflection of reinforced concrete (RC) elements affected by reinforcement corrosion. The focus was on the possibility of estimating the corrosion current intensity on the basis of external measurements of deflections of RC elements subjected to reinforcement corrosion. The method can be used as an element supporting the diagnosis of RC structures. The article presents an example of analytical and numerical deflection calculations, on the basis of which an attempt was made to estimate the corrosion current density. The obtained results were considered satisfactory, which is sent for further considerations, and above all for experimental verification of the proposed method. The analysis was based on the theoretical work of a simply supported beam, whose analytical results were verified using the finite element method. For the purposes of theoretical considerations, the impact of corrosion of the beam reinforcement was assumed in the form of a history of changes in the intensity of the corrosion current obtained in another research work. Finally, the obtained results confirmed the assumptions regarding the possibility of estimating the corrosion current density on the basis of the deflection of the analyzed beam.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48291169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of the behavior of reactive powder concrete RC deep beams by strengthening shear using near-surface mounted CFRP bars","authors":"A. A. Azeez, A. Jaafar, M. M. Yussof, A. A. Blash","doi":"10.1515/eng-2022-0433","DOIUrl":"https://doi.org/10.1515/eng-2022-0433","url":null,"abstract":"Abstract The applications of modern materials especially reactive powder concrete for improving concrete structures have been significantly growing in recent years. Great conduct properties creep, shrinkage, little permeability, ultra-high strength, and expanded safety against corrosion are the important features of Reactive Powder Concrete. In addition, the use of the Near-Surface Mounted technique in recent decades has helped strengthen and repair shears-reinforced concrete (RC) for deep beams using carbon fiber replacement reinforcing bars. The parameters studied in the present research investigated the impact of the maximum load, deflection, stress–strain curve of concrete, first shear crack, crack pattern, and crack width. Considering the aforesaid cause and objective, one specimen of Reactive Powder Concrete RC deep beams has a rectangular cross-section of 150 mm in width, 500 mm in depth, and a total length of 1.2 m. One control specimen was tested for comparison. In addition, 12 control specimens (cylinder and cubes) are used for experimental investigation on the mechanical properties of normal and Reactive Powder Concrete deep beams. Following the specimens’ processing, they were subjected to one concentrated load pressure test through a hydraulic jack. Moreover, six core drill specimens were taken from those deep beams to obtain the real mechanical properties of those beams, including maximum stress, modulus of elasticity, density, stress–strain curve, and Poisson’s ratio, after subjecting them to the pressure machine. Depending on the results, the ultimate strength, deflection, and first shear crack capacity for the specimens (RPCDB1P-4NSM & RPCDB1P-8NSM) have increased by (21, 25), (47, 27), and (133, 150)%, respectively, compared with (CDB1PC20). Moreover, the specimens above have reduced the first shear crack width by (9, 33.25)% respectively compared with (CDB1PC20) at 65% of the ultimate shear load.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45389950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Punching shear of reinforced concrete slabs bonded with reactive powder after exposure to fire","authors":"R. Atea, Hasanain M. Dheyab, Rasha A. Aljazaari","doi":"10.1515/eng-2022-0393","DOIUrl":"https://doi.org/10.1515/eng-2022-0393","url":null,"abstract":"Abstract Reactive powder concrete (RPC) is one of the most recent and significant advancements in the world of building. Due to its higher concrete characteristics, it has a common excessive benevolence happening in the globe at the moment, excessive ductility, shrinkage resistance, and corrosion and abrasion resistance. Investigated is the method for amending the RPC experimentally in punching shear slab action and the properties of construction material to investigate properties of volumetric ratios of steel fiber, and silicas fume, tensile steel ratio, the most important component for construction is reinforced concrete, which works well with other materials to create structures in any shape that is needed. In the present research, investigational work of RC slab with (1,000 × 1,000 × 60) mm dimensions was tested. This study aims to see how the relative volume of steel fibers (Vf) and silica fume content (Sf) affect the actions of RC slabs after being exposed to fire. It originated that a concrete mix containing 2% steel fibers improved the RPC slab's cracking and final punching shear. The existence of reactive powder increases fire resistance. This study's experiment aimed to see how reactive powder and Slab's ultimate punching shear strength were affected by replacement ratio. Whenever a fire is present. After fire exposure, the initial and subsequent stiffness of reinforced concrete slabs reduced considerably the temperature grew from 25 to 750°C.","PeriodicalId":19512,"journal":{"name":"Open Engineering","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49028465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}