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Trucks and Haulers
Published in John E. Schaufelberger, Giovanni C. Migliaccio, Construction Equipment Management, 2019
John E. Schaufelberger, Giovanni C. Migliaccio
Trucks and haulers are flexible pieces of construction equipment that are used to carry bulk construction materials such as soil, sand, gravel, rock, or asphalt. Hauling with these units is generally quite economical, because they are able to travel at relatively high speeds. Trucks and haulers usually are the most cost-effective types of hauling equipment when the haul distances are greater than about 2 miles. At shorter distances, scrapers may be more economical, because of the cost of loading trucks and haulers. Trucks also are used on urban construction projects, because scrapers generally are not allowed on paved roads or in urban settings. Since trucks and haulers are not self-loading, they must be loaded by another piece of equipment. The most common types of loading equipment are loaders (either wheeled or tracked), front shovels, excavators, clamshells, and draglines. Key contractor decisions are selection of the type and size truck or hauler, the type and size of loading equipment, and the number of trucks to use on a specific construction task. As will be illustrated in this chapter, proper fleet balancing is critical to minimizing the cost of a loading and hauling operation.
Review of surface mining equipment selection techniques
Published in G. N. Panagiotou, T. N. Michalakopoulos, Mine Planning and Equipment Selection 2000, 2018
Equipment selection possess a challenge to the surface mining industry. Partial parameter list should to be considered when selecting equipment is; Mine parameters: Life of mine, bench height, floor condition, optimum depth of cut, haul distance, and haul grade.Characteristic of the overburden: Soil characteristics, swell factor, material size, and ground pressure.Types of equipment: Scrapers, front-end loaders, hydraulic excavators, backhoes, and electric shovels, trucks, conveyors, etc.Equipment characteristics: Bucket size, operating life, depth of cut, work cycle, and speed.Production rate: Yearly amount of material to be excavated.Operating costs: Including maintenance and repairs, tires, fuel, lubrication, electricity, and wages.
General introduction
Published in Adedeji B. Badiru, Handbook of Industrial and Systems Engineering, 2013
Being struck by, or caught in-between moving parts of, heavy equipment are the leading sources of associated accidents. Heavy equipment includes front-end loaders, rubber-tired and tracked crawler tractors/bulldozers, skid steer bobcats, elevating scrapers, tandem powered scrapers, rubber-tired backhoes and tracked hydraulic excavators, on- and offroad haulage vehicles, asphalt pavers and associated support equipment, industrial tractors, fork lifts, concrete mixers, and pump trucks. The Carnegie Mellon Robotics Lab is currently developing an autonomous robotic agricultural tractor and a computer-controlled construction excavator, which uses a pair of scanning laser rangefinders to recognize the truck, detect obstacles, monitor the dig face, and monitor soil in the truck bed. Another innovation to reduce equipment hazards is the on-guard vehicle sensing and warning system, which monitors conditions external to vehicle and arrests motion to prevent run-over accidents (Luppino, 2002). It is also being developed to monitor conditions of operator and issue alerts to those working in area.
Dynamic simulation analysis on loader’s working device
Published in Australian Journal of Mechanical Engineering, 2018
Construction machinery plays an important role in the construction of modern buildings and undertakes the important task of providing various manufacturing equipment and production tools for economic construction. Loader is an important equipment in the field of construction machinery with the advantages of fast working speed, high efficiency, good mobility and light operation. There is a big gap between domestic loader technology development level and western developed countries, along with poor product R&D ability as well as difficultly adapting to the market demand. Thus, it is of great engineering application value to study the working device of loader by using modern design method. Since the early 1980s, a large number of experts and scholars at home and abroad have done a lot research work on loaders’ working devices by using modern advanced methods such as dynamic simulation analysis. In literature (Yang, Shen, and Li 2010; Yuan and Niu 2013), ZL50 and ZL80 wheel loaders are chosen as the research objects, and the virtual prototype models of the two types of loaders’ working devices are created in ADAMS. The kinematics analysis module in the software is used to study the working performance of the working device, including bucket translation, automatic flattening and so on. At the same time, the optimal design module in ADAMS is used. The performance of the above work is optimised reasonably and the result is satisfactory. In the literature (Zhang, Zhang, and Zang et al. 2010), by taking the working device of ZL50C wheel loader as the research object, the ADAMS software is selected as the research tool, and the simulation model of the working mechanism is established in the software. These working performance parameters are optimised and the overall performance of the optimised working device is greatly improved. In the literature (Bo, Zhu, and Ye 2014), the key technologies of modelling and simulation of rigid-flexible coupling system are studied, and the joint use of UG is put forward. ADAMS and ANSYS are the three softwares to establish the rigid-flexible coupling model of the mechanism, which enhances the interoperability when using the three softwares to optimise the design of the working device, accuracy and reliability. In this paper, the common domestic ZL50 wheel loader was taken as the research object.
Determining the environmental impact of material hauling with wheel loaders during earthmoving operations
Published in Journal of the Air & Waste Management Association, 2019
Hassanean S.H. Jassim, Weizhuo Lu, Thomas Olofsson
The framework and methodology presented in this work provide a way to overcome problems caused by a lack of real-world data on the environmental impact of construction equipment, and could be used in future studies to measure, assess, and monitor the environmental effects of construction operations. It would be desirable to benchmark the model’s performance by comparing its planning stage predictions to construction phase emissions data gathered using emissions measurement systems such as PEMS. Discrete event simulation was shown to be a powerful tool that can integrate equipment performance data and information on site conditions to accurately describe real situations encountered in construction operations and overcome the problem of lacking data on earthwork activities. Moreover, ANN-based modeling was shown to be an effective tool for solving complex nonlinear problems and clarifying the relationships between independent factors in construction operations. The ANN-based models developed in this work accurately predicted the environmental impact of hauling operations during earthworks in terms of the fuel consumption of wheel loaders. In future, they could be used to help practitioners identify environmentally optimal wheel loader operating configurations. A sensitivity analysis of the ANN-based model revealed the dominant factors affecting wheel loaders’ fuel consumption as well as factors with significant effects on inter-cycle variation in environmental impact. These findings provide important new insights into wheel loader duty-cycles that support the findings of Abolhasani et al. (2008) and will facilitate the development of improved models for assessing the environmental impact of earthmoving operations, which are a major source of emissions in the construction sector. The load factor equation presented here, which depends on the loose density of the hauled materials, can be used to estimate the engine state of wheel loaders under various loads and accurately reflects the impact of material type on wheel loaders’ fuel consumption. Importantly, the results obtained here show that the environmental impact of wheel loader operations can be controlled by selecting an equipment configuration in which the size of the wheel loaders is well-matched to the tasks at hand. The equipment utilization rate was shown to strongly affect wheel loaders’ energy use and emissions per cubic meter of material loaded, both of which are minimized by selecting a machinery configuration that minimizes idle times and ensures that the wheel loaders’ bucket payloads do not exceed the upper limit specified by the manufacturer. The case study demonstrated that the newly developed model can be used in practice to assess and minimize the environmental impact of earthmoving operations by helping practitioners make optimal equipment selections. This work could be extended by using a questionnaire to gather data on practical earthwork operations that could be compared to the sensitivity analysis presented herein. In addition, it would be desirable to assess the potential environmental impact of other factors that may affect the operational characteristics of construction machines such as operating modes and maintenance levels for wheel loaders.