Risk perception of construction equipment operators on construction sites of Turkey

WOS: 000351970500008Turkey has been an attractive country for construction industry in the last decade. Many large-scale construction projects, which have been realized by both international and local construction firms, helped the economy and provided employment opportunities for many. At the same time, many construction workers have been losing their lives on construction sites, which involve the usage of heavy equipment on a daily basis. Past research studies suggest that employee participation and their perception of safety risks could be valuable for determining and eliminating hazards on construction site. Therefore, this study aimed to determine and evaluate the risk perception of construction equipment operators in Turkey. The study is mainly based on a questionnaire survey performed in 51 construction projects that involved 198 heavy equipment operators. A statistical analysis was first performed on the results of the survey to observe the frequency distribution of parameters, such as safety and health training, using flagger, experience, type of equipment, working conditions and other project related data. Then, statistical methods such as, t-test, ANOVA analysis, Kruskall Wallis one way analysis of variance, and Mann-Whitney U test were performed to seek statistically meaningful differences in risk perception of operator groups with different attributes. Results revealed the importance of safety and health training as well as working with an assistant, such as a flagger. It was observed that operators who took safety and health training and operators who worked with flaggers perceived risk differently than others. It was also found that the project type influences the risk perception of equipment operators due to diversity of construction equipment activities performed, as well as number of incidents occurred in those projects. Relevance to industry: The authors expect this research to lead to discussion and further research on risk assessment for construction industry. The risk assessment findings of this study, in particular, could help the safety professionals detect possible unforeseen risks and design safety and health plans for construction sites that require usage of heavy equipment on a daily basis. Heavy equipment manufacturers could also devise a similar research that involves operators' risk perception to design more ergonomic and safe equipment. (C) 2014 Elsevier B.V. All rights reserved

Evaluating noise exposure levels of laboratories in civil engineering education

###EgeUn###One of the most highly found physical contaminants in the working environment is noise, which cause negative health effects associated with the hearing system that could lead to temporary or permanent deafness. Therefore, occupational noise is a risk that is being monitored at work places by measuring exposure levels and developing preventive measures. However, there are certain work places, such as laboratories used for research and education, which are not usually considered to be noisy, even though some activities could generate harmful noise levels for laboratory personnel and students. This study aimed to evaluate and highlight the risks associated with civil engineering laboratories, where noisy experiments are conducted on a regular basis. Thirteen commonly conducted experiments from four different civil engineering areas were selected for measurement. The highest noise exposure levels of each experiment were determined and compared with the limits imposed by different regulations and standards. The results showed that three of the experiments (grinding aggregate by ball grinder, crushing aggregate by jaw crusher and cutting concrete by saw) generate noise above the limits determined by standards and regulations. Preventive measures to reduce noise levels for these experiments were recommended and a noise control flow chart for similar work environments was presented. (C) 2019 Institute of Noise Control Engineering.Scientific Research Projects of Ege UniversityEge University [2015-MUH-031]The study was financially supported by Scientific Research Projects of Ege University (No. 2015-MUH-031). The authors would like to thank the personnel of civil engineering laboratories of Ege University for their help and participation

Evaluating noise exposure levels of laboratories in civil engineering education

One of the most highly found physical contaminants in the working environment is noise, which cause negative health effects associated with the hearing system that could lead to temporary or permanent deafness. Therefore, occupational noise is a risk that is being monitored at work places by measuring exposure levels and developing preventive measures. However, there are certain work places, such as laboratories used for research and education, which are not usually considered to be noisy, even though some activities could generate harmful noise levels for laboratory personnel and students. This study aimed to evaluate and highlight the risks associated with civil engineering laboratories, where noisy experiments are conducted on a regular basis. Thirteen commonly conducted experiments from four different civil engineering areas were selected for measurement. The highest noise exposure levels of each experiment were determined and compared with the limits imposed by different regulations and standards. The results showed that three of the experiments (grinding aggregate by ball grinder, crushing aggregate by jaw crusher and cutting concrete by saw) generate noise above the limits determined by standards and regulations. Preventive measures to reduce noise levels for these experiments were recommended and a noise control flow chart for similar work environments was presented. © 2019 Institute of Noise Control Engineering.2015-MUH-031The study was financially supported by Scientific Research Projects of Ege University (No. 2015-MUH-031). The authors would like to thank the personnel of civil engineering laboratories of Ege University for their help and participation

Utilization of fly ash and ground granulated blast furnace slag as an alternative silica source in reactive powder concrete

Reactive powder concrete (RPC) is an ultra high strength cement-based material. Cement and silica fume (SF) content of RPC are generally rather high compared to the conventional concrete. The aim of this study is to decrease the cement and SF content of RPC using with fly ash (FA) and/or ground granulated blast furnace slag (GGBFS). The effect of these mineral admixtures on compressive strength of RPC has been investigated under autoclave curing. In the first stage, the effect of autoclave time and SF content on compressive strength was determined. In the second stage, SF was gradually decreased and cement was replaced with FA and/or GGBFS at different proportions. The microstructure was investigated by scanning electron microscope (SEM). Test results indicate that, the utilization of FA and/or GGBFS in RPC is possible without significant mechanical performance loss. SEM micrographs revealed the tobermorite having different morphology. (C) 2008 Elsevier Ltd. All rights reserved

Effect of fine to coarse aggregate ratio on the rheology and fracture energy of steel fibre reinforced self-compacting concretes

In this study, the influence of aggregate grading and steel fibre properties on the flow properties and fracture energy of steel fibre reinforced self-compacting concrete (SFRSCC) has been investigated. Two types of hooked-end steel fibres at three different dosages (20,40 and 60 kg/m(3)) were incorporated into self-compacting mixtures having similar paste contents but different fine to coarse aggregate (FA/CA) ratios (0.94, 1.72 and 2.50 by weight). Besides the flowability and passing ability of fresh concrete, the mechanical properties of hardened concrete including the fracture energy have also been investigated. The relations between flexural parameters and fibre orientation were established by image analysis technique. Test results showed that hooked-end steel fibre inclusion into the plain self-compacting concrete negatively affects the flowability and passing ability of the mixture. Increasing FA/CA ratio enhances these rheological parameters and provides better fibre orientation. On the other hand, increasing FA/CA ratio decreases the fracture energy of plain SCC mixtures and the fibre incorporated series which were less affected from fibre inclusion follow the same trend with the plain SCC. The proper FA/CA ratio for the best rheological and mechanical performance depends on the fibre content, aspect ratio and their influence on the flowability of the mixture. In order to obtain better fibre orientation and hence higher fracture energy, relatively higher FA/CA ratios should be used when the fibre content and aspect ratio are relatively high