检索结果-内蒙古大学图书馆

Experimental Vibration Analysis for civil engineering Structures - EVACES 2023 - Volume 2

作者： Aloisio, Angelo Tomasi, Roberto De Santis, Yuri Hillberg, Thomas Pasca, Dag Pasquale Giordano, Pier Francesco Rosso, Marco Martino Limongelli, Maria Pina Bedon, Chiara Department of Civil Construction-Architectural and Environmental Engineering Università degli Studi dell’Aquila L’Aquila Italy Faculty of Science and Technology Norwegian University of Life Sciences As Norway Institute for Construction and Material Sciences Unit of Timber Engineering University of Innsbruck Innsbruck Austria Oslo Norway Department of Architecture Built Environment and Construction Engineering Politecnico di Milano Milan Italy Department of Structural Geotechnical and Building Engineering Politecnico di Torino Turin Italy Department of Engineering and Architecture Università degli Studi di Trieste Trieste Italy

ISBN: (纸本)9783031391088

Timber floors can be susceptible to human-induced vibration due to the low density of timber compared to other construction materials. Human-induced vibration is a complex problem due to many involved parameters. As in many dynamic systems, the response depends on the dynamic parameters and the excitation source. Therefore, more advanced assessment methods must consider suitable human-floor interaction models. The most straightforward classification is based on the dynamic response. The increasing use of timber in commercial and office buildings requires more complex analysis than in residential dwelling. Therefore, the timber research community has proposed specific procedures for low-frequency floors. The dynamic response of timber floors improves under a combination between timber and other materials with complementary properties. Timber composite floors are generally made of wood products coupled with concrete, steel, glass or other wood products through a continuous or discontinuous connection. This paper reviews the most recent findings and research trends on vibration issues related to timber floors. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Floors

来源：评论

学校读者我要写书评

暂无评论

Exploring a recurrent neural network (RNN) earned value based model for predicting lost labour value in construction projects

引用

Discover civil engineering 2024年第1期1卷 1-18页

作者： Egwunatum, Samuel I. Osadola, Opeyemi A. Oboshior, Joel Department of Quantity Surveying Construction Economics Unit Federal University of Technology Owerri Nigeria Department of Construction Federal University of Technology Owerri Nigeria Department of Civil Engineering Ambrose Alli University Ekpoma Nigeria

This study explores the application of deep learning techniques in forecasting labour losses in construction projects. By leveraging the predictive capabilities of ManHour Earned and Estimated ManHour values, this research aims to develop an accurate and reliable model for labour loss forecasting. Utilizing a dataset comprising 105 work items from industry practitioners who employed the Leonard and Moselhi methodology, this study investigates the efficacy of a Recurrent Neural Network (RNN) architecture with Long Short-Term Memory (LSTM) cells. The model's performance is optimized through backpropagation and hyperparameter tuning, focusing on key parameters such as learning rate, batch size, dropout rate, and number of epochs. To ensure the model's generalizability and mitigate overfitting, regularization strategies and performance monitoring are employed. The predictive potential of the model is evaluated through integration into a real-time sequence production job and deployment into an enabled environment. Results demonstrate the model's capacity for accurate labour loss forecasting, enabling proactive measures to enhance productivity and minimize unnecessary claims. Although this study focuses on building projects, its findings have broader implications for process and manufacturing engineering, where productivity losses and associated labour losses are significant concerns. The practical application of this research lies in its potential to assess and counter labour loss claims, disputes, warrants, and demands in construction projects, ultimately contributing to improved project management and reduced financial losses.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A review of bio-inspired geotechnics-perspectives from geomaterials,geo-components,and drilling&excavation strategies

Biogeotechnics

引用

Biogeotechnics 2023年第3期1卷 52-65页

作者： Wengang Zhang Jiaying Xiang Ruijie Huang Hanlong Liu Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing 400045China School of Civil Engineering Chongqing UniversityChongqing 400045China National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing 400045China

As urbanization progresses,the demand for high-rise buildings and underground spaces is growing,and the need for firm geotechnical construction materials,efficient excavation methods,accurate testing instruments,and innovative geotechnical engineering theories and technologies is *** investigating the phenomena of strengthening and toughening in nature,hydrophobic and ice-phobic,friction anisotropy and drilling as well as excavation,etc,researchers have found that organisms have distinctive external morphology and *** imitating the external morphology,structural characteristics or movement mechanism of organisms,novel ideas,new principles,and innovative theories can be provided for the innovation and sustainable development of geotechnical *** paper mainly expounds on the bio-inspired application in geotechnical engineering from three perspectives:geo-materials,geotechnical components,and drilling&excavation equipment,and lists typical application *** conclusion,this paper presents a summary and prospects of bio-inspired geotechnical engineering,offering fundamental insights for future research.

关键词： Bio-inspiration Geotechnical engineering Bio-inspired materials Bio-inspired component Bio-inspired equipment

来源：评论

学校读者我要写书评

暂无评论

The application of steel slag aggregate for concrete pavement: Mechanical properties and stability

引用

Journal of the Chinese Institute of civil and Hydraulic engineering 2022年第8期34卷 739-748页

作者： Vo, Duy-Hai Do, Ngoc-Duy Hwang, Chao-Lung Liao, Min-Chih Lu, Chien-Ming Department of Civil Engineering Danang University of Technology and Education Danang912301 Viet Nam Department of Civil and Construction Engineering National Taiwan University of Science and Technology Taipei10607 Taiwan Department of Civil and Construction Engineering National Taiwan University of Science and Technology Taipei10607 Taiwan

This study aims to evaluate the performance of steel slag aggregate concrete for concrete pavement. Three kinds of Ladle furnace slag (LFS) with different expansion ratios were used as fine aggregate, while two kinds of Rotary kiln slag (RKS) named as Acid (AC) and Alkaline (AK) steel slag were used as coarse aggregate to manufacture the concrete specimens. The mix-proportions were designed using the Densified mixture design algorithm (DMDA) method with various water-to-binder (w/b) ratios of 0.3, 0.4 and 0.5. Compressive strength, splitting tensile strength, ultrasonic pulse velocity (UPV), electrical surface resistivity (ESR), and length change performance under autoclave tests were conducted to evaluate the concrete samples' mechanical properties and dimension stability up to 56 days of curing ages. The findings illustrated that the w/b ratio significantly affected the engineering properties of concrete samples. The LFS-II, with an expansion range of 0.2% ~ 0.4%, presented better mechanical properties than other fine aggregate kinds. AK concrete showed a more excellent engineering property than AC concrete. The LFS-I exhibited good stabilization after autoclaved test, while the higher expansion fine aggregate was not stable under autoclaved analysis. © 2022, Chinese Institute of civil and Hydraulic engineering. All right reserved.

关键词： Tensile strength

来源：评论

学校读者我要写书评

暂无评论

Modelling and Optimization of Clean and Affordable Electricity Solution for Small-Scale Savings and Credit Cooperatives(SACCOs)

引用

Energy engineering 2023年第4期120卷 791-810页

作者： Xiaomei Lin Samuel Bimenyimana ChenWang Godwin Norense Osarumwensa Asemota Jeanne Paula Ihirwe Aphrodis Nduwamungu Etienne Ntagwirumugara Athanase Gace Changfu Yuan Yaowen Chen Changtai Li Shilpi Bora YiYi Mo Jiyu Lai Mabao Wu Yong Tang Merit M.Huang College of Science and Technology The Open University of FujianFuzhou350013China Intelligence and Automation in Construction Provincial Higher–Educational Engineering Research Centre Huaqiao UniversityXiamen361021China African Centre of Excellence in Energy for Sustainable Development University of RwandaKigali4285Rwanda Morayo College Nairobi999070Kenya Department of Economics and Management Hebei University of TechnologyTianjin300401China College of Science and Technology University of RwandaKigali4285Rwanda Fujian Baichuan Construction Technology Co. Ltd.HuliXiamen361021China Haoqi(Xiamen)Construction Technology Co. Ltd.HaicangXiamen361021China School ofDesign Ajeenkiya D Y PatilUniversityPune412105India College of Civil Engineering Huaqiao UniversityXiamen361021China College of Transportation and Civil Engineering Fujian Agriculture and Forestry UniversityFuzhou350100China Highway Southeast Engineering Co. Ltd.Xiamen361100China Fuzhou Sinotom Information Technology Co. Ltd.Fuzhou350001China

Renewable energy exploitation is among the development strategies set by the government of Rwanda on the roadmap to 2023/2024 universal electricity access and theUnitedNations plans by *** previous studies oncleanenergy technologies inRwandahavemostly focusedonhouseholds’usagebut there are currentlynostudies describing the feasibility of clean energy technologies for financial *** skepticism on renewable energy in Africa was previously reported by some *** realized that most SACCOs(Savings and Credit Co-Operatives)in Rwanda use diesel technology for backup/emergency electricity supply,taking consideration of abundant solar resources in Rwanda,having seen the viability and feasibility studies from other countries of renewable energy for different institutions(financial included);thiswork uses theHOMEREnergy Software and the electricity load profile of a typical SACCO in Rwanda to analyse the affordability and viability of on-site renewable energy generation for SACCO in *** results reveal that a solar PV systemwith storage can be the optimal solution(with levelized cost of electricity(LCOE)of 0.713$/kWh which is cheaper than 0.73$/kWh for diesel technology)for SACCOs located in both off-grid areas and grid-connected areas(with 0.041$/kWh LCOE which is lower than the current electricity tariff in Rwanda).The findings in this work can serve as basic tools/materials for policy drafters in Rwanda on how financial institutions can contribute to climate change mitigation through self-renewable energy exploitation.

关键词： HOMER energy solar energy SACCO in Rwanda climate change mitigation

来源：评论

学校读者我要写书评

暂无评论

construction Research Congress 2022

Construction Research Congress 2022

引用

construction Research Congress 2022: Project Management and Delivery, Controls, and Design and Materials, CRC 2022

作者： Ahmed, Muaz O. El-Adaway, Islam H. Coatney, Kalyn Dept. of Civil Architectural and Environmental Engineering Missouri Univ. of Science and Technology RollaMO United States Hurst-McCarthy Professor of Construction Engineering and Management Professor of Civil Engineering and Founding Director of Missouri Consortium of Construction Innovation Dept. of Civil Architectural and Environmental Engineering and Dept. of Engineering Management and Systems Engineering Missouri Univ. of Science and Technology RollaMO United States Dept. of Agricultural Economics Mississippi State Univ MississippiMS United States

ISBN: (纸本)9780784483978

The global and national spending on public infrastructure projects continues to increase tremendously. Accordingly, contractors need to adopt efficient bidding strategies to cope with the legal requirement of competitive bidding within the public infrastructure projects. Moreover, contractors usually acquire the services of subcontractors to handle large projects. However, despite the previous research efforts on developing bidding models, there is still a lack of research that tackles the multi-stage construction bidding, where subcontractors submit quotations/bids first and general contractors bid second for the whole project. As such, this paper aims to develop a game-theoretic bidding model for multi-stage construction bidding. To this end, the authors utilized an interrelated methodology comprised of: (1) investigating existing bidding models that are based on a game theory approach;(2) deriving of a bid function for the multi-stage construction bidding following the low bid method where the lowest bidder is the winner;(3) simulating multi-stage bidding environment;and (4) validating the derived bid function and simulation model utilizing data of 808 US public infrastructure projects. Results indicate that the derived bid function gives general contractors a competitive advantage by reducing the occurrence and magnitude of earning negative profits (known as the winner's curse) while winning a reasonable number of projects;and hence, resulting in a higher expected profit. Ultimately, this study adds to the body of knowledge by providing a bidding model for the multi-stage construction bidding that shall aid contractors in dealing with the uncertainties within the associated decision-making process. © 2022 ASCE.

关键词： Contractors

来源：评论

学校读者我要写书评

暂无评论

Agent-based modeling approach for evaluating underground logistics system benefits and long-term development in megacities

引用

Journal of Management Science and engineering 2022年第2期7卷 266-286页

作者： Wanjie Hu Jianjun Dong Jingfeng Yuan Rui Ren ZHIlong Chen Helan Cheng College of Architecture and Civil Engineering Beijing University of TechnologyBeijing100124China College of Civil Engineering Nanjing Tech UniversityNanjing211800China Department of Construction Management and Real Estate Southeast UniversityNanjing210096China College of Defense Engineering Army Engineering University of PLANanjing210001China Nanjing KENTOP Civil Engineering CO. LTDNanjing210041China

Mobility,pollution,and other barriers against sustainable goods movement are pushing local administrators to seek innovations in urban transportation *** urban underground logistics system(ULS)has been recognized as a prospective alternative to realize large-scale automated freight distribution within and around *** paper proposes an integrated approach combing system dynamics and agent-based modeling to evaluate the long-term development and operating status of a city-wide ULS *** project boundaries regarding underground network expansion,stakeholders’attributes,and social-environmental benefit metrics were structured as eight highly-interacted agent *** decision variables of agents in terms of supply-demand equilibrium,investment plan,pricing-to-market and willingness-to-pay were incorporated into three formulized subsystem *** empirical perspective,the urban territory of Beijing,China,was taken as a case to simulate the development footprints of ULS project under different funding options and market acceptance *** show that ULS has significant competence with respect to service capacity and profitability,while enabling billions of dollars of external cost-saving ***,the comprehensive performance of ULS project regarding economic incomes,benefits,market demand,and construction schedule can reach satisfactory trade-offs through adaptively adjusting the funding policies,incentives and pricing portfolios during project development.

关键词： Underground logistics system Sustainabletransport Project development Cost-and-benefit System dynamics Agent-based modeling

来源：评论

学校读者我要写书评

暂无评论

Research on buffer structure and flow field simulation of swash plate plunger type hydraulic transformer

引用

High technology Letters 2022年第4期28卷 425-433页

作者： WANG Xiaojing HUO Shuhang LI Wenjie Beijing Key Laboratory of Performance Guarantee on Urban Rail Transit Vehicle Beijing University of Civil Engineering and ArchitectureBeijing 102616P.R.China Beijing Engineering Research Center of Monitoring for Construction Safety Beijing University of Civil Engineering and ArchitectureBeijing 102616P.R.China School of Mechanical and Power Engineering Harbin University of Science and TechnologyHarbin 150080P.R.China

In order to solve the problem of excessive noise and vibration during the operation of the hydraulic transformer,an optimization method of valve plate damping hole structure is proposed to alleviate the phenomenon of pressure ***,the mathematical model of oil pressure gradient in the plunger cavity is established,and the incremental equation of pressure change is ***,a kind of buffering structure is proposed,the corresponding relationship between the pressure change and the envelopment angle of the buffering hole and the aperture size is determined by analyzing the oil pressure change curve in the plunger ***,the flow field models with buffering holes are established,and the transient simulation of the pressure change process under the optimal solution is carried out with ANSYS software and the flow field pressure distribution contours are *** the analysis of simulation results,it is concluded that the optimal envelope angle of the three buffer holes ofA-T-B-Ais 5°,and the optimal aperture is 1.8 mm,1.6 mm,and 1.7 mm,*** buffer hole can achieve a better-buffering effect in the range of variable pressure angle[0°,101°].The buffer hole structure can effectively alleviate the pressure shock and reduce the noise level,which lays a foundation for the design and theoretical research of hydraulic transformers.

关键词： hydraulic transformer pressure shock buffer structure flow field simulation dynamic grid

来源：评论

学校读者我要写书评

暂无评论

Experimental study on the movement law of overlying rock non-pillar coal overhead mining

引用

Journal of Mountain Science 2023年第6期20卷 1759-1773页

作者： LI Yong ZHENG Jing WANG Feng-nian MA Xin-gen ZHANG Rui-xue SUN Ying-ying YIN Jian-bin TAO Zhi-gang College of Geoscience and Surveying Engineering China University of Mining and Technology-BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology-BeijingBeijing 100083China Shanxi Provincial Transportation Technology Research and Development Co.Ltd. Key Laboratory of Highway Construction and Maintenance Technology in Loess AreaTransportation IndustryTaiyuan 030000China Huaneng Coal Technology Research Co.Ltd. Beijing 10o83China State Key Laboratory for Geo Mechanics and Deep Underground Engineering China University of Mining and Technology-BeijingBeijing 10083China School of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing 100083China

Pillarless coal mining technology is a new practical *** on the compensating mechanical behavior of the Negative Poisson’s Ratio(NPR)anchor cable on the roof,the roadway was successfully retained by the top cutting and pressure relief *** study utilizes the Digital Speckle Monitoring(DIC monitoring),stress-strain monitoring,and infrared thermal imaging systems to conduct physical model experiment of similar materials from the displacement,stress-strain,and temperature fields to investigate in depth the fracture change law of the overlying *** addition,it uses FLAC3D numerical simulation to invert the surface displacement *** results show that the non-pillar overhead mining under the 110 mining method has little influence on the rock crack in the middle of the coal seam,and the crack development area is mainly concentrated in the overlying rock mass of the upward coal *** compensatory mechanical behavior of NPR anchor cable and the dilatation characteristics of rock mass have a good effect of retaining roadway along goaf,and can also reduce surface *** 110 mining method provides a scientific basis for ecological environment protection and the development of other kilometer deep soft rock high ground stress underground projects.

关键词： No pillar mining Overhead mining NPR anchor cable Physical model of similar materials FLAC3D Numerical simulation Motion of overburden

来源：评论

学校读者我要写书评

暂无评论

Some Issues of the Kyiv TV Tower Renovation After the Missile Attack 6th

Some Issues of the Kyiv TV Tower Renovation After the Missil...

引用

6th International Scientific Conference on Environmental Challenges in civil engineering, ECCE 2024

作者： Shymanovskyi, Oleksandr Baran, Wieslaw V. Shymanovskyi Ukrainian Institute of Steel Construction V. Shymanovskyi St. 2/1 Kyiv02125 Ukraine Faculty of Civil Engineering and Architecture Opole University of Technology Katowicka 48 Opole45-061 Poland

ISBN: (纸本)9783031737756

The paper presents some issues concerning the renovation of the Kyiv TV tower after the missile fire that followed the attack on Ukraine by the Muscovite invaders. It is noted that the 385-m-high Kyiv TV tower was inaugurated on July 30, 1973, and at the time of construction as well as for the next 37 years, it was the highest freestanding welded steel lattice tower in the world, and many new solutions were applied during the design of the tower. It is noted that on March 1, 2022, the Muscovite invaders launched a targeted double missile attack on the TV tower, which, despite some damage, withstood the impact of the blast wave. It is noted that after the attack on the TV tower, an inspection of its technical condition was carried out, which indicated that the joint of the tower metal structures at elevation + 56,000 m, which was directly in the center of the explosion, suffered the most damage. In some other metal structures, only separate holes, cracks, and dents of various sizes were found, which were formed due to the impact of the missile fragments. Design features for new TV tower structures intended to replace the destroyed elements and strengthen partially damaged elements are defined based only on solutions that would not interrupt the existing structural layout and stress state of the tower. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

关键词： Television towers

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：