Construction Machine Operators Research Articles

Features of designing building general plans

The construction master plan (contgenplan) is the general plan of the construction site, which shows all existing and planned permanent buildings and structures, as well as temporary buildings necessary for construction and assembly works. The purpose of the budget plan is to organize the construction industry on the site, which would ensure the creation of the necessary production and living conditions for workers, the reception and delivery of materials, semi-finished products and structures to the workplace, the normal operation of construction machines and mechanized installations, uninterrupted supply of water and energy resources. There are two types of construction master plan: general site and object.
 The general site budget plan is drawn up during the development of the construction organization project and covers the entire territory of the urban residential massif (microdistrict, block) or cultural and household complex. The facility budget plan is part of the construction project and covers the territory related to one facility or, in some cases, to several. At the stage of the construction project, an object budget plan is developed, which specifies and details the decisions of the site-wide budget plan. The budgenplan should show: entrances and exits, unloading points, entry into dangerous areas, the construction of roads and sidewalks, their width and connection to the designed buildings.
 The budget plan should show storage facilities, temporary buildings, the organization of communication lighting and dispatching of the construction site, the organization of providing the facility with electricity, water, steam, compressed air, and oxygen. Before placing mechanized equipment on the construction site, it is necessary to determine the types and number of cranes, stationary lifts, as well as their installation locations. After that, it is necessary to calculate the operating zones of the cranes, taking into account the specifics of architectural and structural solutions and the construction conditions of the facility.

System for recognising and monitoring the technical condition of construction machines

Assessing and predicting machine reliability and failure risks is an essential requirement of international standards for machine safety. The existing methods for determining reliability indicators and risk assessment are based on statistical information about failures and faults that occur during machine operation. Collecting, accumulation and processing of statistical data about failures of machines by traditional methods does not provide the necessary efficiency and reliability of the received information. In this connection forecasting of reliability, estimation, and risk management in production and operation of machines with necessary reliability is not a simple task. Modern diagnostic systems offer unlimited possibilities for the timely acquisition and transmission of information concerning the technical condition of machines, which can be used for the solution of problems. Depending on the structure and location of the transmission, storage and processing of the information, a distinction is made between stationary or remote diagnostics systems. With the modern development of communication and data transmission, remote systems are improved versions of stationary diagnostic systems. In the article the questions of formation of a recognition system and monitoring of a technical condition of building machines by means of the diagnostic information are considered. The main purpose of the development and implementation of the system is to ensure the reliability and safety of operation of construction machines. In order to solve this problem, it is necessary to recognize and promptly prevent the occurrence of failure, which requires the allocation of a special class of intermediate states, called pre-emergency. The results of the implementation of the recognition and monitoring system of construction machines with the help of diagnostic information are presented.

Determination of diagnostic errors in the system of diagnostic parameters of hydraulic drives of construction and road machinery

Problem. The article considers the issue of increasing the efficiency of operation of construction machines by improving systems of measures that provide an effective system for diagnosing hydraulic drive elements. The considered existing methods prove that a more effective determination of indicators of diagnostic parameters in a system with the error of the diagnostic devices themselves for diagnosing hydraulic drives of construction and road machines will be the equipment that gives the necessary result with lower overall costs for diagnostics with minimal costs, including the cost of diagnostic equipment, its operation and development, as well as the cost of preparing the hydraulic drive for diagnosis. Goal. The goal is determination of diagnostic errors in the system of diagnostic parameters of hydraulic drives of construction and road machinery. Methodology In technical diagnostics, test and functional diagnostics are used. During functional diagnosis, actions are used that are set by the working processes of the hydraulic drive. During test diagnostics, special test actions are applied to hydraulic units. The technical condition of hydraulic units is evaluated based on the reaction to these actions. Functional and test actions, between which there are no clear boundaries, are carried out only within the technical characteristics of the hydraulic unit. Results. A more effective determination of the indicators of diagnostic parameters in a system with the error of the diagnostic devices themselves for diagnosing hydraulic drives of construction and road machines will be the equipment that gives the required result with lower overall costs for diagnostics. These costs include the cost of diagnostic equipment, its operation and development, as well as the cost of preparing the hydraulic drive for diagnosis. Originality. Accuracy in this case is determined by the analytical dependence that connects the diagnostic parameters and other methods depending on the type of this dependence. Thus, it was established that the use of a lower rotation frequency of the pump compared to its passport data increases the share of leaks in the total flow of the working fluid and allows to reduce the diagnostic error by 40...60% without additional costs for the purchase and operation of measuring devices. Changing the parameters is possible within the technical characteristics of the hydraulic unit. Methods of ensuring accuracy are currently insufficiently used to improve diagnostics, which is an unused reserve for increasing its efficiency. Practical value. Efficiency of operation of construction machines is increased by improving the systems of measures that provide an effective system for diagnosing hydraulic drive elements.

Psychological Effects of Heart Rate and Physical Vibration on the Operation of Construction Machines: Experimental Study.

BackgroundA construction method has emerged in which a camera is installed around a construction machine, and the operator remotely controls the machine while synchronizing the vibration of the machine with the images seen from the operator's seat using virtual reality (VR) technology. Indices related to changes in heart rate (HR) and physical vibration, such as heart rate variability (HRV) and multiscale entropy (MSE), can then be measured among the operators. As these indices are quantitative measures of autonomic regulation in the cardiovascular system, they can provide a useful means of assessing operational stress.ObjectiveIn this study, we aimed to evaluate changes in HR and body vibration of machine operators and investigate appropriate methods of machine operation while considering the psychological load.MethodsWe enrolled 9 remote operators (18-50 years old) in the experiment, which involved 42 measurements. A construction machine was driven on a test course simulating a construction site, and three patterns of operation—riding operation, remote operation using monitor images, and VR operation combining monitor images and machine vibration—were compared. The heartbeat, body vibration, and driving time of the participants were measured using sensing wear made of a woven film-like conductive material and a three-axis acceleration measurement device (WHS-2). We used HRV analysis in the time and frequency domains, MSE analysis as a measure of the complexity of heart rate changes, and the ISO (International Standards Organization) 2631 vibration index. Multiple regression analysis was conducted to model the relationship among the low frequency (LF)/high frequency (HF) HRV, MSE, vibration index, and driving time of construction equipment. Efficiency in driving time was investigated with a focus on stress reduction.ResultsMultiple comparisons conducted via the Bonferroni test and Kruskal-Wallis test showed statistically significant differences (P=.05) in HRV-LF/HF, the vibration index, weighted acceleration, motion sickness dose value (MSDVz), and the driving time among the three operation patterns. The riding operation was found to reduce the driving time of the machine, but the operation stress was the highest in this case; operation based on the monitor image was found to have the lowest operation stress but the longest operation time. Multiple regression analysis showed that the explanatory variables (LH/HF), RR interval, and vibration index (MSDVz by vertical oscillation at 0.5-5 Hz) had a negative effect on the driving time (adjusted coefficient of determination R2=0.449).ConclusionsA new method was developed to calculate the appropriate operating time by considering operational stress and suppressing the physical vibration within an acceptable range. By focusing on the relationship between psychological load and physical vibration, which has not been explored in previous studies, the relationship of these variables with the driving time of construction machines was clarified.

Construction of a Skill Evaluation System Based on database‐driven Approach for a Hydraulic Excavator

In industries, particularly the construction field, the number of workers is decreasing because of the falling number of young new hires and the increasing number of existing elderly workers. Therefore, it is important to improve the productivity of each worker at a construction site. At many construction sites, operation and decision‐making skills of construction machine operators are required, and work productivity depends on these skills of the operators. However, the number of elderly skilled operators is decreasing, and it is necessary to accurately train young unskilled operators to develop the aforementioned skills in order to improve productivity. Thus, a system that can quantitatively evaluate the operation skills of the operator is required. This study proposes a system that can quantitatively evaluate the operator's skills by using a database‐driven technique. The proposed method is applied to the swing operation of a hydraulic excavator. Furthermore, skill evaluation is carried out by multiple operators, and the effectiveness of the proposed method is verified. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

Scenarijski simulacijski model za optimalnu alokaciju građevinskih strojeva

Metode optimizacije imaju veliku važnost pri sužavanju izbora resursa na konacni i pri alokaciji resursa u svim fazama projekata. To se narocito odnosi na složena projektna okruženja gdje je potrebno provesti alokaciju resursa (strojeva) na vise građevinskih projekata u njihovim raznim fazama i prioritetima. U radu se predlaže model koji se zasniva na algoritmu visekriterijske optimizacije i rangiranja scenarija suboptimalnih programa serijskog visekanalnog rada građevinskih strojeva pri konacnom broju strojeva za izbor, te izlucivanje presjeka optimalnih programa i/ili scenarija programa u složenom okruženju.

THU0417 Occupation and Risk of Developing Rheumatoid Arthritis

BackgroundThe etiology of rheumatoid arthritis (RA) is still fairly unknown. Finding occupations associated with the risk of disease could generate knowledge about occupational hazards that might be involved in disease...

Noise Exposure among Machine Operators on Construction Sites in South Johor, Malaysia

Machines operators expose to excessive noise in the workplace that may lead to hearing damage. This study investigates construction machine operators noise exposure levels for eight hours or time weighting averages (TWAs), relationship TWA with machine noise emission level, the practices of using hearing protection devices (HPDs) and working in a closed machine cab. Heavy and non-heavy machine operators at five construction sites involved with excavation and piling activities were selected and measured by using dosimeters. 68% of operators were exposed to TWA of 85 dBA and 18% of the operators exceeded the permissible limit. 40% of operators work inside a closed machine cab, 18% wear earplugs and only 16% practiced both. Both operators of heavy machines (except excavators) and dump trucks are exposed to TWA > 90 dBA if they work in open machine cabs. The TWAs were found well correlated (r=0.41) with the machine noise emission, which ranged between 84 dBA to 125 dBA. Furthermore, this study proposes the type of HPD for the operators of typical machine to minimise the risk of hearing loss.

Multiimaging Sensor Data Fusion-Based Enhancement for 3D Workspace Representation for Remote Machine Operation

In incompletely characterized environments such as construction sites, remote machine operation is the preferred—and sometimes the only—safe and efficient solution for the operation of construction machines. When it comes to the operation of remote-controlled construction machines, a human—machine interface is needed so that even in the case of an unstructured environment (such as a construction site), the operator can interact with the machine in a safe and efficient manner. The human—machine interface needs to have the capability of realistically representing a three-dimensional (3D) workspace that provides information feedback to the remote operator. Workspace representation methods that are currently in use have certain limitations—they are time consuming and labor intensive and require high-performance computers. A major objective of this study is the development of an efficient means of representing a workspace in 3D that has the capacity to provide interactive visual feedback to the operator of remote-controlled construction machines. To achieve this objective, the ability is required to acquire dense, accurate, and visually realistic 3D data that can be converted into high-quality models. This allows creation of a realistic 3D workspace representation of terrain, including objects that might be in proximity to the machine. For this purpose, this study proposes a multiimaging sensor data fusion-based system employing joint bilateral upsampling, which enhances the quality and availability of the information acquired in such an environment. The field experiment results show that combining data acquired with a complementary multiimaging sensor setup allows enhancement of the quality of the information available to the remote operator. The resulting task-specific 3D workspace representation can be successfully incorporated into the development of remote-controlled construction machines that require interactive visual feedback. This provides the opportunity to make human—machine interaction more efficient and to improve the remote operation capability by assisting the operator. Moreover, the proposed multiimaging sensor data fusion-based 3D representation approach has the potential for effective use in a broad class of applications within the construction industry.

Time trends in occupational risks of lung cancer among Swedish men from 1961-1979.

Using data from the Swedish Cancer-Environment Register, time trends in the standardized incidence ratio (SIR) for lung cancer 1961-1979 were studied in different occupations. After adjustments for differences in the SIR with respect to year of birth, only the decreasing trends for blacksmiths and members of the armed forces as well as increasing trends for foundry workers and construction machine operators were significant (p less than 0.05). For bakers and pastry cooks, there was a significant interaction between year of birth and observation period in relation to SIR. Data on smoking habits, obtained from a sample of the population, did not seem to explain the trends.