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Construction Sites (construction + site)

Distribution by Scientific Domains

Engineering	38%

Selected Abstracts

Construction site of a power plant.

CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 8 2009
Courtesy of Evonik Industries (Chem. Eng.
No abstract is available for this article. [source]

Fall hazard control observed on residential construction sites

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 6 2009
OT/L, Vicki Kaskutas OTD
Abstract Background Falls are a leading cause of mortality and morbidity in the construction industry. This study measured fall hazards at residential construction sites. Methods Trained carpenters administered the St. Louis Audit of Fall Risks and interviewed carpenters. The prevalence of fall prevention practices meeting safety criteria was counted and correlations explored. Results We identified a high prevalence of fall hazards at the 197 residential sites audited. Roof sheathing met safety criteria most consistently (81%) and truss setting least consistently (28%). Use of personal fall arrest and monitoring of unguarded floor openings were rare. Safer performance on several scales was correlated. Construction sites of large-sized contractors were generally safer than smaller contractors. Apprentice carpenters were less familiar with their employers' fall prevention plan than experienced workers. Conclusions Safety could be improved with consistent use of recognized fall prevention practices at residential construction sites. Am. J. Ind. Med. 52:491,499, 2009. © 2009 Wiley-Liss, Inc. [source]

Mobile Construction Supply Chain Management Using PDA and Bar Codes

COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2005
H. Ping Tserng
However, extending the construction project control system to job sites is not considered efficient because using notebooks in a harsh environment like a construction site is not particularly a conventional practice. Meanwhile, paper-based documents of the site processes are ineffective and cannot get the quick response from the office and project control center. Integrating promising information technologies such as personal digital assistants (PDA), bar code scanning, and data entry mechanisms, can be extremely useful in improving the effectiveness and convenience of information flow in construction supply chain control systems. Bar code scanning is appropriate for several construction applications, providing cost savings through increased speed and accuracy of data entry. This article demonstrates the effectiveness of a bar-code-enabled PDA application, called the mobile construction supply chain management (M-ConSCM) System, that responds efficiently and enhances the information flow between offices and sites in a construction supply chain environment. The advantage of the M-ConSCM system lies not only in improving the efficiency of work for on-site engineers, but also providing the Kanban-like visual control system for project participants to control the whole project. Moreover, this article presents a generic system architecture and its implementation. [source]

Automatic Palletizing of Concrete Pavement Blocks: An Algorithm for Near-Optimal Assembly

COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 3 2001
Shraga Shoval
Palletizing concrete pavement blocks is a labor-intensive task that requires high levels of workmanship, skill, and concentration. This article proposes an automatic system in which palettes with required design patterns are assembled automatically off-site and then shipped to the construction site. The efficiency of the assembly process can be improved by incorporating automatic equipment consisting of assembly heads and feeders. An algorithm was developed to determine the optimal layout of the feeders (of different blocks) around the palette and the exact assembly sequence of each layer of blocks. Experimental results show that the algorithm is near optimal and that the solutions provided by it reduce palletizing cycle time for various patterns and sizes of concrete block by 20 to 30 percent. [source]

Back analysis of model parameters in geotechnical engineering by means of soft computing

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 14 2003
B. Pichler
Abstract In this paper, a parameter identification (PI) method for determination of unknown model parameters in geotechnical engineering is proposed. It is based on measurement data provided by the construction site. Model parameters for finite element (FE) analyses are identified such that the results of these calculations agree with the available measurement data as well as possible. For determination of the unknown model parameters, use of an artificial neural network (ANN) is proposed. The network is trained to approximate the results of FE simulations. A genetic algorithm (GA) uses the trained ANN to provide an estimate of optimal model parameters which, finally, has to be assessed by an additional FE analysis. The presented mode of PI renders back analysis of model parameters feasible even for large-scale models as used in geotechnical engineering. The advantages of theoretical developments concerning both the structure and the training of the ANN are illustrated by the identification of material properties from experimental data. Finally, the performance of the proposed PI method is demonstrated by two problems taken from geotechnical engineering. The impact of back analysis on the actual construction process is outlined. Copyright © 2003 John Wiley & Sons, Ltd. [source]

A multidegree-of-freedom manipulator for curtain-wall installation

JOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 5 2006
Chang Soo Han
Recently, the trend in architectural forms has been towards larger and taller buildings. Building materials are, therefore, also becoming larger and heavier. Typical construction machineries are not adequate for handling such materials, and most construction works are still managed by a human operator. Construction processes are, therefore, fraught with a number of problems, including frequent accidents, high construction cost, and heterogeneous construction quality depending on the experience of the workers. Automation has been introduced at various sites to address these construction problems. In this paper, the process of a curtain-wall installation in a skyscraper is analyzed, and the prototype of a construction robot for curtain-wall installation (CRCWI) is proposed. Use of the proposed CRCWI can reduce the need for manpower and the construction period and cost, and can assure safety in the curtain-wall construction site. The performance of the proposed CRCWI was verified with a real application test in a skyscraper construction site. © 2006 Wiley Periodicals, Inc. [source]

Rückbau einer 400 m langen Autobahnbrücke unter besonderen Rahmenbedingungen , BAB A 6, Neckarbrücke Mannheim

BAUTECHNIK, Issue 5 2005
Martin Osieja Dipl.-Ing.
Es wird über den Rückbau der alten Neckarbrücke Mannheim im Zuge der BAB A 6 berichtet. Bei diesem Bauwerk bestand jeder der beiden Überbauten aus sechs Bögen mit einer Gesamtlänge von rund 400 m. Je fünf der sechs Bögen wurden durch Sprengen zum Einsturz gebracht. Die beiden Bögen über der Schiffahrtsstraße Neckar durften nicht gesprengt werden und mußten aus diesem Grunde in einzelnen Schritten abgetragen werden. Beim Rückbau waren bestimmte Bedingungen gebührend zu berücksichtigen. Vor allem durften zwei das Bauwerk querende Gashochdruckleitungen in keiner Weise beschädigt werden. Zu ihrem Schutz wurden sie mit beachtlichen Fallbetten überbaut. Der Weg, der zu diesen Fallbetten führte, wird aufgezeigt. Zudem werden die bei den Sprengungen durchgeführten Erschütterungsmessungen sowie deren Ergebnisse vorgestellt. Die mit diesem Rückbau gewonnenen Erfahrungen werden wiedergegeben. Demolition of a 400-metre long expressway bridge under particular circumstances , BAB A 6, Neckar bridge Mannheim. This text is about the demolition of the former Neckar bridge Mannheim, situated along the German federal expressway A 6. This construction was composed of two superstructures, which respectively consisted of six arches. Five of the six arches of each superstructure were blasted. The two remaining arches above the Neckar channel could not be blown up due to vessel traffic, and for this reason had to be gradually dismantled. There were a number of aspects that had to be carefully considered during the demolition, especially the presence of two high-pressure gas pipes that run across the construction site. To prevent damage to the pipes, abundant mounds of sand were placed on top of them. The way that led to these mounds is illustrated in this article. Furthermore, the vibration measurements as well as their results are also presented. The experiences gained from this demolition are illustrated in this article. [source]

Bestimmung der Tunnelinnenschalendicke mit zerstörungsfreien Prüfverfahren

BETON- UND STAHLBETONBAU, Issue 8 2006
Dietmar Mähner Prof. Dr.-Ing.
Der vorliegende Beitrag befaßt sich mit dem Einfluß von zerstörungsfreien Prüfmethoden zur Bestimmung der Tunnelinnenschalendicke und der Auswertung eines auf einer Baustelle durchgeführten Untersuchungsprogramms. Die Bandbreite der Untersuchungen bilden dabei an drei Tunnelblöcken unterschiedlich eingesetzte Meßverfahren und ihre jeweilige spezifische Eignung, verschiedene Meßteams sowie unterschiedliche Meßraster, die jeweils vor und nach der Firstspaltverpressung zum Einsatz kamen und analysiert wurden. Als wichtiger Parameter zum Einfluß der Meßqualität ist hierbei die durchzuführende Kalibrierung der Meßgeräte am Einsatzort zu nennen, die die Grundlage der Meßgenauigkeit bildet. Weiterhin konnte die Qualität bzw. der Erfolg der durchgeführten Firstspaltverpressung mittels eines Injektionsgutes in den Messungen nicht zweifelsfrei bestätigt werden und wurde daher zusätzlich durch Kernbohrungen und endoskopische Aufnahmen überprüft. Mit den daraus gewonnen Erkenntnissen werden wesentliche Aspekte und Empfehlungen aufgeführt, die im Umgang mit den zerstörungsfreien Prüfmethoden zur Dickenbestimmung einer Tunnelschale zu beachten sind und in zukünftige Projekte einfließen sollten. Determining the thickness of tunnel internal shell with non-destructive testing methods This report deals with the influence of non-destructive testing methods for determining the thickness of internal tunnel shells and evaluates the results of examinations performed on a construction site. The investigations cover different measurement techniques performed on three tunnel blocks; also analyzed were the specific advantages of these techniques, the employment measurement personnel and different measurement grids used before and after ridge-gap grouting. An essential parameter influencing the measurement accuracy is the calibration needed by the measurement devices at the site of deployment. Because the measurements were not able to unmistakably confirm the quality or success of ridge-gap grouting through injection, these results had to be examined additionally using drill cores and endoscopy. Permitting a crystallization of essential aspects and recommendations as regards the conduction of non-destructive tests for determining the thickness of tunnel shells, the obtained findings are to be incorporated into future projects. [source]

Die neue Anwendungsnorm DIN V 18197 "Abdichten von Fugen in Beton mit Fugenbändern": Fugenbänder fachgerecht geplant, ausgewählt und eingebaut

BETON- UND STAHLBETONBAU, Issue 11 2005
Rainer Hohmann Prof. Dr.-Ing.
Fugenbänder werden seit Jahrzehnten erfolgreich zur Abdichtung von Bewegungs- und Arbeitsfugen in wasserundurchlässigen Bauwerken aus Beton eingesetzt. Mit der DIN V 18197 "Abdichten von Fugen in Beton mit Fugenbändern" wird nun sowohl dem Planer als auch dem Ausführenden ein Regelwerk zur Verfügung gestellt, in dem neben relevanten Hinweisen für die Planung und eine fachgerechte Handhabung von Fugenbändern auf der Baustelle auch Auswahldiagramme zu finden sind, mit denen der Planer in Abhängigkeit von der Beanspruchung auf einfache Art Fugenbänder auswählen kann. Dieser Beitrag geht auf die wesentlichen die Fugenabdichtung mit Fugenbändern betreffenden Regeln ein und zeigt an ausgewählten Beispielen, wie der Planer das auf seine Belastungen abgestimmte Fugenband mit Hilfe der Auswahldiagramme der DIN V 18197 auswählen kann. The new German Standard DIN V 18197 "Sealing of joints in concrete with waterstops" , waterstops correctly designed, dimensioned and used For decades, waterstops are successfully used for the waterproofing of movement and construction joints in watertight concrete structures. The DIN V 18197 "Sealing of joints in concrete with waterstops", provides a set of rules for both, the planner and the contractor. In addition to relevant details for the design and the professional handling of waterstops on the construction site, selection diagrams are included which, in a simple way, allows the planner to select waterstops in dependence of the loads. This article addresses to the essential rules concerning the joint waterproofing with waterstop and explains by means of several examples and the DIN V 18197 selection diagrams, how the planner can specify a waterstop complying with the loads. [source]

,Why do they hate us?' Reframing immigration through participatory action research

AREA, Issue 2 2010
Caitlin Cahill
Why do ,they' hate ,us'? is a painful starting point for trying to make sense of the tangled web of global restructuring, politics and racism. My discussion draws upon ,Dreaming of No Judgment', a participatory action research project developed with young people in Salt Lake City, Utah that explores the emotional and economic impacts of stereotypes upon immigrant communities. My analysis focuses upon the disjunctures between the dominant immigration discourse and the everyday experiences of young Latino immigrants. Drawing upon borderlands scholarship, starting with embodied everyday lived experiences and concerns, here I consider how the questions, concerns and feelings of young people offer new openings for reframing immigration. In conclusion, I reflect upon how PAR might be a transformative ,construction site' for reworking and responding to social injustices through the arts. [source]

Effects of construction noise on behaviour of and exhibit use by Snow leopards Uncia uncia at Basel zoo

INTERNATIONAL ZOO YEARBOOK, Issue 1 2008
C. E. SULSER
Noise caused by human activities can cause stress in animals. We examined whether noise from construction sites affects the behaviour of and exhibit use by three Snow leopards Uncia uncia at Basel zoo. The behaviour and location of the animals were recorded at 1 minute intervals, using the instantaneous scan sampling method over a period of 216 hours (104 hours on noisy days and 112 hours on quiet days). The animals differed individually in their responses to the construction noise. On noisy days, the Snow leopards generally spent less time in locomotion and more time resting, but even on quiet days, resting was the predominant behaviour performed. Under noisy conditions, they increased social resting and decreased resting alone. Walking and social walking were also reduced on noisy days. Furthermore, the Snow leopards spent considerably more time in the remote off-exhibit enclosure under noisy conditions. Independent of background noise, they stayed more than half of the time in the caves and the forecourts of the outdoor enclosure. On quiet days, the Snow leopards used more sectors of their exhibit than on noisy days. The results indicate that the Snow leopards responded to construction noise by increasing the amount of time spent resting and by withdrawing to the remote parts of their exhibit. [source]

Integration of arbuscular mycorrhiza inoculation in hydroseeding technology: effects on plant growth and inter-species competition

LAND DEGRADATION AND DEVELOPMENT, Issue 6 2007
V. Estaún
Abstract Hydroseeding is a technique increasingly used to establish vegetation on large degraded areas, such as large-scale road construction sites and quarries. Native grasses and legume species are used on rehabilitation and restoration projects as a first step in the recovery of such places, prior to the establishment of native forbs and shrubs that occurs at a slower pace. The effect of mycorrhizal inoculation on the development of nine species of grasses and legumes that can be potentially used in restoration processes in the Mediterranean area was studied, in microcosm experiments under greenhouse conditions. The effect of adding arbuscular mycorrhizal (AM) inoculum to a hydroseeding mixture was also investigated in greenhouse and in field conditions. In the hydroseeding experiments the mycorrhizal inoculum was added to the seed slurry in a jet agitated hydroseeding machine and sprayed to the soil surface with a pressurised spray in a one-step application. The study shows that Glomus intraradices Schenk & Smith BEG72 is able to establish the symbiosis when applied at sowing while Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe BEG116 is not. It also confirms that legumes are more highly mycotrophic than grasses. The results of the hydroseeding experiments demonstrate the establishment of the symbiosis using this technology, both in the greenhouse and in the field. Mycorrhizal inoculation improved above ground plant growth and increased the legumes/grasses ratio. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Work-related injuries among Hispanic construction workers,Evidence from the Medical Expenditure Panel Survey,

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 6 2010
Xiuwen Sue Dong DrPH
Abstract Background Although a large number of Hispanic workers have entered the construction industry, few studies have estimated non-fatal work-related injuries for Hispanic construction workers at a national level. This study examines work-related injury conditions among Hispanic construction workers and assesses disparities between Hispanic and white, non-Hispanic workers. Methods Pooled data were analyzed from a large national population survey, the Medical Expenditure Panel Survey (MEPS), between 1996 and 2002. More than 7,000 construction workers were identified from the MEPS data including 1,833 Hispanic workers and 4,533 white, non-Hispanic workers. Univariate and multivariate analyses were conducted using SAS-callable SUDAAN. Results Hispanic workers differ from white, non-Hispanic workers in demographic and socioeconomic status. After controlling for major risk factors, Hispanic construction workers were more likely than their white, non-Hispanic counterparts to suffer non-fatal work-related injury conditions (OR,=,1.28, 95% CI: 1.00,1.64). Conclusions This study provides important evidence concerning Hispanic workers' safety on construction sites. Enhanced safety and health programs for Hispanic construction workers and improved occupational injury data systems are recommended. Am. J. Ind. Med. 53: 561,569, 2010. © 2010 Wiley-Liss, Inc. [source]

Nonfatal unintentional injuries and related factors among male construction workers in central China

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 6 2010
Lei Zheng
Abstract Background Work-related injuries (WRIs) among construction workers have recently emerged as an important public health issue as the construction industry is booming in China. We investigated nonfatal unintentional work-related injuries and risk factors among male construction workers in central China. Methods A purposive sampling method was used in 2008 to select 1,260 male workers from 24 construction sites. WRIs that occurred in the past 12 months and possible risk factors were asked about in face-to-face interviews. Results Among 1,260 male construction workers, 189 workers reported WRIs. The annual prevalence of nonfatal WRIs was 15.0 per 100 workers (95% confidence interval (CI): 13.0,17.0). The top three leading causes of injuries were collisions (27.3 per 100 workers), cuts/piercings (17.5 per 100 workers), and falls (15.5 per 100 workers). WRIs were significantly associated with high cigarette pack-year index (PYI,,,20 vs. nonsmoker: adjusted odds ratio (OR),=,2.50, 95% CI: 1.31,4.76), serious alcohol consumption (,30ml/day vs. nondrinker: adjusted OR,=,1.73, 95 %CI: 1.12,2.69), not having injury prevention and safety education (adjusted OR,=,2.05, 95% CI: 1.22,3.44), and had depressive symptoms (adjusted OR,=,2.63, 95% CI: 1.22,5.67). Conclusions Our results suggest that annual prevalence of nonfatal construction injuries is high in central China and serious cigarette smoking, serious alcohol consumption, not having injury prevention and safety education, and depressive symptoms are considered important factors for those injuries. Am. J. Ind. Med. 53: 588,595, 2010. © 2010 Wiley-Liss, Inc. [source]

Effectiveness of the training program for workers at construction sites of the high-speed railway line between Torino and Novara: Impact on injury rates

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 12 2009
A. Bena MD
Abstract Background There are very few published studies evaluating the impact of safety and health training on injury outcomes in the construction industry. The aim of this study was to assess the impact of the training program on injury rates at a major railway construction project. Methods The population consisted of 2,795 workers involved in a safety training program at the construction sites of the high-speed railway line Torino,Novara. Two types of analyses were carried out in order to assess the effectiveness of the training program in reducing the number of injuries: (i) a pre,post analysis, which took into account the fact that workers were enrolled at different times and the training intervention did not occur at the same time for all subjects; (ii) an interrupted time-series model, which corrected for the time trend and considered the autocorrelation between individual observations. Results Twenty-nine percent of workers who spent at least 1 day at the construction sites attended at least one training module. Pre,post analysis: At the end of the training program, the incidence of occupational injuries had fallen by 16% after the basic training module and by 25% following the specific modules. Time-series model: Training led to a 6% reduction in injury rates, which was not statistically significant. Conclusions The training program that was implemented had a moderately positive impact on the health of workers. Further studies are being conducted to obtain a more complete assessment of the actual effectiveness of the program in reducing the incidence of injuries. Am. J. Ind. Med. 52:965,972, 2009. © 2009 Wiley-Liss, Inc. [source]