• Korean Journal of Occupational Health Nursing
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• v.29 no.2
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• pp.106-113
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• 2020

Purpose: This study aimed to analyze industrial accident compensation insurance coverage and industrial accidents among concrete mixer truck drivers. Methods: Original data on industrial accidents from 2012 to 2017 were analyzed through descriptive statistics. Results: Industrial accident compensation insurance coverage was 44.6% in 2017. Most concrete mixer truck drivers were affiliated with small businesses. A total of 61 industrial accidents occurred in 2012, 65 in 2014, and 80 in 2017. The major types of industrial accident were falls, slips, and crushes. Conclusion: Because concrete mixer truck drivers are at high risk for industrial accidents, industrial accident compensation insurance coverage and industrial accident prevention should be strongly enforced.

• Journal of Drive and Control
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• v.12 no.4
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• pp.77-81
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• 2015

In general, the gears of mixer reducer for concrete mixer truck make use of the differential type planetary gear system to rotate mixer drum smoothly on the initial conditions. The planetary gear system is very important part of mixer reducer for concrete mixer truck because of strength problem. In the present study, calculating the gear specifications and analyzing the gear bending & compressive stresses of the differential planetary gear system for mixer reducer are necessary to analyze gear bending and compressive stresses confidently, for optimal design of the planetary gear system in respect to cost and reliability. As a result, analyzing actual gear bending and compressive stresses of the planetary gear system using Lewes & Hertz equation and verifying the calculated specifications of the planetary gear system, evaluate the results with the data of allowable bending and compressive stress from the Stress-No. of cycles curves of gears.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.12
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• pp.34-41
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• 2020

Ready-mixed concrete is unconsolidated concrete typically transported to construction sites by using mixer trucks. A proper rotation of concrete is necessary to prevent its solidification in mixer trucks during transport: in accordance with the manufacturing method and quality inspection prescribed in KSF4009, this movement is maintained after the manufacturing of concrete in professional production plants and the addition of water, solid materials, and admixtures. Unfortunately, mixer truck parts wear out over long periods of time. In order to improve the wear resistance of the main part of mixer trucks, we used a steel plate with good wear resistance or partially added a reinforcement plate. In this study, we first tested the properties of concrete (as required for the DEM), and then carried out mixing and discharge simulations to define the actual operating conditions of mixer trucks. For each condition, we calculated the amount and location of wear. The reliability of our results was finally verified by comparing them with the measurement values. Overall, this study provided basic data for an optimal design of mixer trucks: one that would reduce the vehicles' weight and production costs.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.2
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• pp.22-29
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• 1993

A remote control system was developed in order to operate by push-buttons the conventional drum and chute components, which have been operated manually, in a concrete mixer-truck. As actuators, a hydraulic power unit was used for chute operations: two DC motors for drum operations. The devised drum controller consisted of three electric circuits : an analog proportional-integral control circuit, a drum acceleration circuit, and an emergency stop circuit. The remote control system was installed to be tested experimentally and then was evaluated to work successfully with a desirable accuracy.

• Magazine of the Korea Concrete Institute
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• v.14 no.4
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• pp.49-55
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• 2002

레미콘의 생산방식은 콘크리트의 비빔을 정치식 배치플랜트(stationary batch plant)내의 고정믹서로 행하는가, 아니면 운반장비인 트럭 믹서(truck mixer)의 드럼으로 행하는가에 따라서 일반적으로 센트럴믹스(central mix), 쉬링크믹스(shrink mix), 트럭 믹스의 3가지로 분류된다.(중략)

• Korean Journal of Occupational Health Nursing
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• v.28 no.1
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• pp.44-52
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• 2019

Purpose: This study aimed to identify the level of health problems and the factors that affect health problems for concrete mixer truck divers. Methods: The questionnaires were administered to 111 drivers in 6 Remicon workplaces located in D city and 7 Remicon workplaces located in K city from September 10 to 28, 2018. A total of 111 questionnaires were collected and 106 were used, excluding 5 incomplete ones. Data were analyzed with frequency, percentage, $x^2$ test, multiple logistic regression analysis by SPSS/WIN 23.0. Results: The factors affecting subjective health were eating habits, sleeping hours and drinking conditions. The factors that affected chronic diseases were age, eating habits, sleep hours, and drinking conditions. The factors influencing musculoskeletal complaints were work experience, eating habits, and sleep hours. Conclusion: The major influencing factors of health problems were eating habits, sleeping hours. This study suggests that it is necessary to run a systematic health care program for the desirable health behaviors in the communities and industrial fields.

• Journal of Drive and Control
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• v.14 no.1
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• pp.1-7
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• 2017

The power train of a concrete truck mixer reducer includes differential planetary gears to get a large reduction ratio for operating the mixer drum in a compact structure. These differential planetary gears are a very important part of the mixer reducer where strength problems are the main concern. Gear bending stress, gear compressive stress and scoring failure are the main concerns. Many failures in differential planetary gears are due to the insufficient gear strength and resonance problems caused by major excitation forces such as gear mating failure in the transmission. In the present study, where the excitation frequencies are the gear tooth passing frequencies of the mating gears, a Campbell diagram is used to calculate differential planetary gear critical speeds. Mode shapes and natural frequencies of the differential planetary gears are calculated by CATIA V5. These are used to predict gear resonance failures by comparing the working speed range with the critical speeds due to the gear transmission errors of the differential planetary gears.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.271-275
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• 1996

This study was performed to analyze flowing properties with kinds of the super-plasticizer and flowing effects with agitation method of the mixer truck. After that, this study presents the reference data about better flowing method and quality control when flowing concrete is applied in practice.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.3
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• pp.65-71
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• 2011

The concrete mixer truck which is in charge of raw materials in civil engineering construction of the concrete loading, transport, placement, is used $6m^3$, $7m^3$ class in domestic(Korea). But in the case of the international construction fields are utilized $9m^3$ or above class because of the large-scale engineering and construction circumstances. In this paper, to develop a large $9m^3$ class mixer drum and the mixer drum in order to complement the technical and discharge that is responsible for stirring the blades by applying optimal design through implementation of the optimal shape of the concrete in the drum maintenance and placement of high-quality effects on increasing discharge such as advanced conventional drum mixer is to secure and differentiated technology. Large, heavy weight in development and uphold the drum mixer vehicle sub-frame is required to settle the design of the existing class mixer drum frames per $6m^3$ changed to account for changes in slope and length using CATIA V5 3D modeling work was performed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.131-132
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• 2011

This study analyzes the yearly-best delivered size range of truck mixer based on the specified mix, Water to Binder Ratio, aggregate proportion and unit amount with statistical method targeting on Kyeongi and Kyeongsang province and compares with the similar materials of Japan to propose as a basic standard for the quality control of mixer truck. As a result, in case of the Water to Binder Ratio of these areas, it is higher than Japan's due to the excessive safety rate reflecting the changes of differential value impact and unit amount, and the unit amount's standard deviation is very large by reflecting the changes of the amount used and chemical admixture susceptibility. In case of aggregate proportion, the frequency rate is about 50%, which is very similar value with Japan's one.