Periodica Polytechnica-Civil Engineering最新文献_第3页

Locating Method for Pick-up and Drop-off Spots for Shared Autonomous Vehicle-based Mobility Services 基于共享自动驾驶汽车的出行服务上下车点定位方法

4区工程技术

Periodica Polytechnica-Civil Engineering Pub Date : 2023-09-20 DOI: 10.3311/ppci.22541

Dahlen Silva, Csaba Csiszár

{"title":"Locating Method for Pick-up and Drop-off Spots for Shared Autonomous Vehicle-based Mobility Services","authors":"Dahlen Silva, Csaba Csiszár","doi":"10.3311/ppci.22541","DOIUrl":"https://doi.org/10.3311/ppci.22541","url":null,"abstract":"To provide safety to users and not disturb traffic flow, autonomous vehicles in shared on-demand mobility services cannot stop everywhere; thus, pick-up and drop-off (PUDO) spots must be dedicated or established for them. Our research objective is to propose a method to locate the PUDO spots for shared autonomous vehicle-based mobility services as this topic has been barely studied. The number of required PUDO spots is calculated, and the location is chosen considering the urban environment, walking radius, vehicle occupancy, and time for boarding and alighting among other parameters. Different from some methods applied to shared mobility, we consider the existing infrastructure (e.g., parking spaces) as potential locations for PUDO spots. The method is applied to a study case, demonstrating the applicability and providing the main findings: (i) the required number of PUDO spots decreases if willingness to walk increases; (ii) with a 3-min walking radius, 83% of curbside parking spaces can be repurposed, and 100% is reached with a 10-min walking radius; (iii) the minimum of 55% of curbside parking spaces can be repurposed with 10-min walking radius and without locating PUDO spots in private parking. Using our method, cities can determine the quantity of PUDO spots and their locations, being prepared in advance for the required changes in the existing infrastructure as well as the freed-up space to be repurposed.","PeriodicalId":49705,"journal":{"name":"Periodica Polytechnica-Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136308729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental Analysis of an Innovative Double Strap Joint Splicing of GFRP Bars by NSM Methods for Strengthening RC Beams 新型GFRP筋双带拼接法加固RC梁的试验分析

4区工程技术

Periodica Polytechnica-Civil Engineering Pub Date : 2023-09-18 DOI: 10.3311/ppci.22681

Slobodan Ranković, Radomir Folić, Andrija Zorić, Todor Vacev, Žarko Petrović, Dušan Kovačević

{"title":"Experimental Analysis of an Innovative Double Strap Joint Splicing of GFRP Bars by NSM Methods for Strengthening RC Beams","authors":"Slobodan Ranković, Radomir Folić, Andrija Zorić, Todor Vacev, Žarko Petrović, Dušan Kovačević","doi":"10.3311/ppci.22681","DOIUrl":"https://doi.org/10.3311/ppci.22681","url":null,"abstract":"The double strap joint splicing of glass fiber reinforced polymer (GFRP) bars for reinforced concrete (RC) beams strengthening, applying the near surface mounting (NSM) method, has been proposed in the paper. The proposed method consists of application of the supplementary GFRP bars symmetrically positioned in the cut-off zone of the main GFRP reinforcement. The performances of this splicing method have been experimentally tested for the most unfavorable case of the GFRP reinforcement cut-off in the maximal bending moment zones. During the experiment, the varied parameter has been overlapping length of the bars, taking values of 20∅ and 40∅. Evaluation of the splicing technique is done comparing the experimental results with the results of the behavior of beams strengthened by GFRP bars without cut-off and with cut-off, but without splicing. Experimental research encompassed analysis of strength, stiffness, ductility, crack pattern, strains in the steel, GFRP reinforcement and concrete, and the failure modes of the beams. It has been shown that in case of the cut-off of the GFRP bar, strengthening effectivity decreases for 39%, and that in the case of bypassing the cut-off using double strap 20∅ and 40∅ long, strengthening effectivity decreased 23%, and 14% respectively, compared to the beam without GFRP bar cut-off. Using extrapolation, it has been shown that double strap with length of 60∅ provided strength equivalent to the case without cut-off. The result of application of this splicing method of the additional GFRP bars is significant increase of strength and serviceability of the strengthened RC beams.","PeriodicalId":49705,"journal":{"name":"Periodica Polytechnica-Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135202520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Influence of Brittleness of Interlayers on the Failure Behavior of Bedding Rock; Experimental Test and Particle Flow Code Simulation 夹层脆性对顺层岩石破坏行为的影响实验测试和粒子流模拟代码

4区工程技术

Periodica Polytechnica-Civil Engineering Pub Date : 2023-09-18 DOI: 10.3311/ppci.23023

Rahim Mortezaei, Seyed Davoud Mohammadi, Vahab Sarfarazi, Reza Bahrami

{"title":"The Influence of Brittleness of Interlayers on the Failure Behavior of Bedding Rock; Experimental Test and Particle Flow Code Simulation","authors":"Rahim Mortezaei, Seyed Davoud Mohammadi, Vahab Sarfarazi, Reza Bahrami","doi":"10.3311/ppci.23023","DOIUrl":"https://doi.org/10.3311/ppci.23023","url":null,"abstract":"In the present study, the effects of angle and brittleness of interlayers on the shear failure behavior of notched bedding rock have been scrutinized using experimental shear tests and particle flow code (PFC) simulation. Notched bedding models with dimensions of 20 cm × 24 cm × 5 cm containing soft interlayer and hard interlayer were prepared. The ratio of compressive strength to tensile strength in soft gypsum and hard gypsum are 12 and 7.8, respectively. The layer angel changed from 0° to 90° with an increment of 15°. The lengths of notches in each model are similar and were equal to 20 mm, 40 mm, and 60 mm. Models were tested by Punch shear by displacement loading rates of 0.05 mm/min. Results showed that pure tensile fracture was developed from the tip of the notch, and propagated in the direction of the shear loading axis till coalescence with the model boundary. Whereas soft brittle gypsum has less deformability in comparison to hard ductile gypsum therefore the continuity of shear displacement associated with crack growth in soft interlayer was less than that in hard interlayer. Also, soft brittle gypsum has less shear strength in comparison to hard ductile gypsum therefore the shear strength of bedding rock has maximum value when hard ductile gypsum was occupied more percentage of shear surfaces. The failure mechanism was alike in both the numerical simulation and the experimental test.","PeriodicalId":49705,"journal":{"name":"Periodica Polytechnica-Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135203170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tomographic Reconstruction of Atmospheric Water Vapor Profiles Using Multi-GNSS Observations 基于多gnss观测的大气水汽剖面层析重建

4区工程技术

Periodica Polytechnica-Civil Engineering Pub Date : 2023-09-15 DOI: 10.3311/ppci.20559

Bence Turák, Abir Khaldi, Szabolcs Rózsa

{"title":"Tomographic Reconstruction of Atmospheric Water Vapor Profiles Using Multi-GNSS Observations","authors":"Bence Turák, Abir Khaldi, Szabolcs Rózsa","doi":"10.3311/ppci.20559","DOIUrl":"https://doi.org/10.3311/ppci.20559","url":null,"abstract":"Continuously operating reference stations (CORS) provide augmentation services for the highly accurate, cm-level GNSS positioning needs of land surveyors, agriculture, and even autonomous vehicles. These stations have accurate coordinates, thus they can be used to estimate the signal delay caused by the neutral atmosphere including the atmospheric water vapor. The estimated zenith wet delay (ZWD) is in a close correlation with the integrated water vapor in the atmospheric column. Since a ground station tracks several satellites at every epoch, one could also estimate the slant tropospheric delays, which can provide information on the spatial distribution of the atmospheric water vapor, too. This paper introduces a near real-time multi-GNSS processing approach to estimate slant wet tropospheric delays and a coupled tomographic reconstruction technique to estimate the 3D wet refractivity model that can be assimilated in numerical weather models. The estimated zenith tropospheric delays (ZTDs) and tropospheric gradients are used to restore the slant wet delays (SWD) affecting the observed satellite-receiver range. The SWDs are used as input for a tomographic reconstruction algorithm providing the wet refractivities in a pre-defined voxel model. The derived refractivity profiles have been validated with radiosonde observations. The results show that our GNSS tomography approach could reconstruct the refractivities with the uncertainty of 10 ppm below 3 km of altitude and of 0.3 ppm at the altitude of 10 km in terms of standard deviation.","PeriodicalId":49705,"journal":{"name":"Periodica Polytechnica-Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Impact of Brick Powder Specific Surface Area on Cement Replacement in Mortar Mixes: A Sustainable and Cost-effective Solution for the Construction Industry 砖粉比表面积对砂浆混合物中水泥替代的影响:建筑业可持续和经济有效的解决方案

4区工程技术

Periodica Polytechnica-Civil Engineering Pub Date : 2023-09-12 DOI: 10.3311/ppci.22643

Somaya Ben Abbou, Issam Aalil, Khalid Cherkaoui

{"title":"The Impact of Brick Powder Specific Surface Area on Cement Replacement in Mortar Mixes: A Sustainable and Cost-effective Solution for the Construction Industry","authors":"Somaya Ben Abbou, Issam Aalil, Khalid Cherkaoui","doi":"10.3311/ppci.22643","DOIUrl":"https://doi.org/10.3311/ppci.22643","url":null,"abstract":"This study examined the use of clay brick powder (CBP) as a partial substitute for cement in mortar mixes. Five mixes were tested, each differing by the fineness of the CBP, obtained by grinding brick waste for different durations (30, 60, 90, 120 minutes). Several parameters were evaluated; apparent density, porosity, spread, ultrasonic pulse velocity (UPV), flexural and compressive strength, and the pozzolanic activity index. The results indicate that, when the brick powder is ground for 60 minutes, the spread of the mortar exceeds 95% compared to the reference mortar. The addition of CBP appears to increase the water absorption and porosity of the mortars, without significantly influencing their apparent density. Most samples have a UPV close to 4000m/s, attesting to satisfactory mechanical properties. The use of 20% CBP in replacement of cement leads to a decrease in flexural strength. However, this drop is less when the specific surface area of the CBP is close to that of cement. As for compressive strength, a decrease is also noted with the introduction of CBP, but this decrease can be mitigated by using CBP with a specific surface area similar to that of cement. These factors can significantly influence the pozzolanic activity of the mortar mix. Furthermore, our investigations into environmental and economic analyses show that the use of cement mixes including CBP results in a significant decrease in energy consumption and CO2 emissions. More specifically, the replacement of 20% of cement with CBP of different granulometries has led to promising results.","PeriodicalId":49705,"journal":{"name":"Periodica Polytechnica-Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135878734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Prediction of Restrained Shrinkage of New-to-old Concrete Interface 新老混凝土界面约束收缩预测

4区工程技术

Periodica Polytechnica-Civil Engineering Pub Date : 2023-09-11 DOI: 10.3311/ppci.22430

Huili Wang, Dequan An, Feng Nie, Hangshuai Zhao, Chunli Xu

{"title":"Prediction of Restrained Shrinkage of New-to-old Concrete Interface","authors":"Huili Wang, Dequan An, Feng Nie, Hangshuai Zhao, Chunli Xu","doi":"10.3311/ppci.22430","DOIUrl":"https://doi.org/10.3311/ppci.22430","url":null,"abstract":"The focus of this study is on the shrinkage differences between new and old concrete, which can cause cracks at the bonding surface of the interface. The effects of various factors on shrinkage, such as the content of shrinkage reducing admixtures (SRA) the content of basalt fibers (BF) and the roughness at the new-to-old concrete interface (RI) are also examined. In this research, nine groups old-new concrete composite specimens were tested for shrinkage to gather experimental data. The restrained shrinkage mechanical model (RSMM) was deduced, and the restrained shrinkage model based on grey correlation analysis (RMGC) was proposed. The effectiveness and convenience of both prediction methods were evaluated by comparing their results to the experimental data. It was determined that the RMGC was more effective and convenient. Additionally, the research found that as the content of SRA and BF increases, shrinkage decreases. The effect of SRA was found to be more significant. As RI increases, shrinkage undergoes an initial increase and then decreases. The study can be used to inform the design and construction of structures that use both new and old concrete.","PeriodicalId":49705,"journal":{"name":"Periodica Polytechnica-Civil Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135980897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Weibull Analysis of Charpy Impact Test in Short Date Palm Fiber Reinforced Epoxy Composite 短枣棕榈纤维增强环氧复合材料夏比冲击试验的威布尔分析

IF 1.8 4区工程技术

Periodica Polytechnica-Civil Engineering Pub Date : 2023-09-08 DOI: 10.3311/ppci.22500

Adel Boulebnane, D. Djeghader, T. Tioua

引用次数: 0

Reliability Analysis of the Slope Stability of Homogeneous Earth Dam under Seismic Loading 地震荷载作用下均质土坝边坡稳定性可靠度分析

IF 1.8 4区工程技术

Periodica Polytechnica-Civil Engineering Pub Date : 2023-09-06 DOI: 10.3311/ppci.22537

Lynda Belazouz, K. Bouzelha, H. Hammoum, Ouali Amiri, Nacim Khelil

{"title":"Reliability Analysis of the Slope Stability of Homogeneous Earth Dam under Seismic Loading","authors":"Lynda Belazouz, K. Bouzelha, H. Hammoum, Ouali Amiri, Nacim Khelil","doi":"10.3311/ppci.22537","DOIUrl":"https://doi.org/10.3311/ppci.22537","url":null,"abstract":"Earth dams are widespread throughout the world and their safety is the overriding concern of civil engineers, especially in regions with high seismic activity. This contribution presents a deterministic and reliability-based approach of the slope stability analysis of homogeneous earth dam under seismic loading. The hydrostatic loading as well as the saturation line in the dam body is considered for different design situations to investigate the effects of water level fluctuations on earth dam slope stability. Seismic loading is introduced by horizontal and vertical pseudo-static forces, while the considered failure mode is circular slip, analyzed with the classical method of slices. Given the nature of the soils, uncertainties about their properties must be considered in the assessment of the slope stability. These uncertainties can be quantified by a reliability analysis. The proposed reliability method is approached by the failure probability assessment of the slope stability of an earth dam based on Monte-Carlo simulation. The used random variables are the mechanical shear properties of the embankment body as well as the acceleration coefficient of the seismic zone. For the failure probability evaluation, the log-normal distribution law was used to generate the random variables. A computer program was developed using Matlab®. The developed approach was applied, for a practical example, to analyze the slope stability of an earthen dam located in Médéa (Algeria), whose dimensions are realistic. The results obtained with the developed analytical model were compared with those obtained with the Flac2D© software. The confrontation turned out to be satisfying.","PeriodicalId":49705,"journal":{"name":"Periodica Polytechnica-Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82561264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Deflection of a Partially Composite Beam Considering the Effect of Shear Deformation 考虑剪切变形影响的部分组合梁挠度

IF 1.8 4区工程技术

Periodica Polytechnica-Civil Engineering Pub Date : 2023-08-25 DOI: 10.3311/ppci.22319

Hamid Hamli Benzahar, M. Chabaat, H. Ayas

引用次数: 0

Optimizing Landfill Capacity: A Numerical Study of the Slope Inclination Variation Impact on Landfill Storage Capacity and Its influence on the Safety Factors under Different Models 填埋场容量优化:不同模型下边坡倾角变化对填埋场库容影响及其对安全系数影响的数值研究

IF 1.8 4区工程技术

Periodica Polytechnica-Civil Engineering Pub Date : 2023-08-25 DOI: 10.3311/ppci.22790

Feten Chihi, G. Varga

{"title":"Optimizing Landfill Capacity: A Numerical Study of the Slope Inclination Variation Impact on Landfill Storage Capacity and Its influence on the Safety Factors under Different Models","authors":"Feten Chihi, G. Varga","doi":"10.3311/ppci.22790","DOIUrl":"https://doi.org/10.3311/ppci.22790","url":null,"abstract":"As an attempt to enhance landfill capacity and extend its lifespan, this research explores the effect of slope inclination on landfill storage capacity and its implementation on the safety factors using numerical simulations. A geometric approach was used to determine the capacity change with inclination, and a new probabilistic calculation method, which accounts for the heterogeneity of waste layers, was employed to analyze the safety factor for different slope angles. Over 100 conducted calculations for each inclination were used to investigate the effect of slope variation on landfill safety. The results show that increasing inclination leads to a significant increase in landfill capacity. The safety factor results indicate that the conventional method, assuming homogenous waste, classifies 1:3 and 1:2 slopes as safe, while the new suggested method showed that a 2:3 inclination could be considered safe, especially since the calculation is not considering the safety-enhancing effect of daily cover layers. This study highlights the importance of considering the heterogeneity of waste layers in safety factor analysis, and the use of multi-layered nonhomogeneous calculation method, which provides more flexibility in design parameters. This research presents a significant step forward in constructing safe and cost-effective landfills. The use of a new probabilistic calculation method in designing landfills leads to more accurate and reliable results while maintaining safety standards. This research has important implications for the design and management of landfills and can be used as a guide for future studies in this field.\u0000 ","PeriodicalId":49705,"journal":{"name":"Periodica Polytechnica-Civil Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90978650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0