The present study was conducted on eighty-two scaffolders, which in their daily schedule performed various carrying load activities. The physiological and psycho-physiological approaches were used to ...determine the maximum carrying load. The scaffolders were divided into 21-30 years, 31-40 years and ≥41 years age groups. In the physiological approach, the experimental data were collected through field and laboratory studies, which included maximum oxygen intake rate, scaffolders heart rate (HR), and its variability. In the psycho-physiological approach, random loads were assigned to identify the load carrying limits of scaffolders belonging to different age groups. The average working HR varied from 125-148 bpm, and the average maximum oxygen intake rate was 1.69 (0.17) l/min, 1.64 (0.23) l/min, and 1.51 (0.19) l/min, respectively, for scaffolders of selected age groups while carrying scaffold poles or boards, guardrails and ladders. The electromyography (EMG) results during load carrying activity in head mode (p<0.02) and shoulder mode (p<0.0.5) found that the trapezoid(r) muscle displayed a gradual increase in EMG values with increased load. In conclusion, maximum load-bearing capacity was estimated for scaffolders of selected age groups using the physiological and psycho-physiological approaches.
A Measurement Method of Carrying Load on a Truck ISHIZAKA, Akio; NARABAYASHI, Tatsuo; OZAKI, Kouichi
Transactions of the Japan Society of Mechanical Engineers Series C,
2005, Letnik:
71, Številka:
705
Journal Article
Odprti dostop
The carrying load on a truck is usually measured by a truck scale or a portable measuring device of carring load. These are the method of measuring the sum of the weight of the truck itself and the ...carrying load. On the other hand it is also thinkable that the value of the carrying load is given by using the elastic deformation that the carrying load produces on a truck body. The proposed method here is one using the strains of front and rear axle induced by the load. In this paper it is proved that this method properly gives the value of the carrying load. If the above method would be realized and the value of load is visually indicated, it is greatly expected that this method effectively prevents carring the over load.
Because of the economic effectiveness and high productivity of welding, contemporary load carrying structures of materials handling and earth-moving machines mostly are manufactured by this ...technology. Actually every product must be designed and made to a required level of quality. In industrial practice, this level is estimated on the basis of a set of factors belonging to one of three main groups: operational safety, economics, and activities of competitors. Within the scope of the first group the required level of quality is obligatory and must be certified. The general rules for meeting this requirement are described in the International Standards ISO 9000-9004 and European Standards EN 29000-29004. According to these Standards every fabricated and previously designed product must fulfil essential aspects of the term quality, expressed as 'conformance with requirements', in which fatigue life always plays an essential role (it is the main feature of quality). The fatigue life is created primarily within the design and development process and subsequently in the fabrication phases. The quality of any industrial product can be divided into quality of design and quality of workmanship. In the case of welded structures the quality is determined first by the type of joint (butt, fillet, etc.), and second by defects located in the weld joint. These problems are addressed using the particular example a telescopic boom of a truck crane. Factors affecting fatigue life, like the type of weld joint and the defects are considered, always as a function of the loading intensity.
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