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Introduction to Tire Engineering
Published in Brendan Rodgers, Tire Engineering, 2020
Truck tire design, compounds, and construction have been optimized for each of the vehicle classes and axle positions, but essentially fall into one of five types, namely steer axle tire, drive axle tire, trailer axle, on-/off-road steer axle tire, and on-/off-road drive axle tire. Again, there are many subsets to this, such as specific tires for buses, recreation vehicles, straight trucks, and tractor–trailer combinations. In all cases, the tread patterns are essentially a rib design, a lug pattern, or a combination of the two, depending on the design profile for the tire (Figure 1.8). Similarly, farm tires are designed for the wheel position, the tractor front or steering axle, which tend to be primarily bias in construction, with a rib tread design, rear drive axles, which largely use radials with a lug tread design, and implements which are bias and tend to have flotation qualities, i.e., which will have a wide footprint to avoid sinking into loose soils and to minimize soil compaction. Earthmover tires would typically fall into one of six categories, depending on the application, which are backhoe, loader, truck, grader, scraper, and dozer. Aircraft tires are designed for either commercial aircraft, business and general utility applications, helicopters, and the military. Tires for each of these applications will have a unique construction, reinforcement, and an optimized set of compounds designed to ensure that the tire meets the required service demands.
Whole-Body Vibration
Published in Neil J. Mansfield, Human Response to Vibration, 2004
Tools used by the machine can be a source of vibration. Sometimes vibration is an essential part of the process (e.g., ride-on rail grinders, hydraulic breaker attachments, driving or piling machines, tamping machines). In these cases the frequency of vibration should be selected to be effective for the task but out of the sensitive range of the operator. Other tools (e.g., backhoe loader excavators) are hydraulically driven and the mechanisms should be designed such that a smooth operation is achieved. The recent move from direct linkage to servo control for some types of machine provides opportunities for development of idealized mechanisms for vibration reduction. Finally, the correct tool should be used for the task (e.g., excavator buckets should not be used for piling).
Construction
Published in Nathalie Schauner, Icold Committee on Concrete Dams, 2020
Equipment typically required for the preparation of the layer/lift surface, for the different joint treatments discussed below, includes: Water curing system; either hoses with nozzles to manually spray a fine water mist, or stationary water misters. The misting system must reach the entire joint surface under treatment.Vacuum truck. Preferable with full-width undercarriage vacuum intake.Manual blowers and vacuum cleaners, to remove water from surface puddles where it is not possible to use the vacuum truck, or where the vacuum truck does not achieve an adequate result.Loader or backhoe-loader equipped with cylindrical brushes (of horizontal axis; vertical axis types are harmful). The various types of brushes are discussed below.Hydro-blasting machine mounted on a truck or on a kart, with pressure in the range of 500–1000 bar.Mini-dumpers, or skid-steer loaders (both better rubber-tracked than wheeled), to haul the debris of the cleaning, brushing and hydro-blasting outside the surface of the layer/lift under joint treatment. The above-mentioned loader or backhoe-loader can be also used for this purpose when not being used for brushing.
Gravity and gravity-pump sewage systems including energy embodied in each system – case studies
Published in Urban Water Journal, 2021
Taking into account all three of the aforementioned concepts (LCC, EE, LCA), a sewage system’s lifetime can be completely assessed, which is the main aim of this article. Another aim is to present the basic values of energy embodied into the materials and devices used in gravity and gravity-pump sewage systems. The energy needed to dig a trench and a wide excavation has been taken into consideration. It has been assumed that the builder is male and is performing hard physical work. Therefore, the energy demand has been estimated at the level of 200 kcal/h, which is equal to 0.2326 kW (Jędruszczak and Romanowska–Słomka 2011). As for the work of machines, it has been assumed that the work of a bulldozer and an excavator will be done by a backhoe loader of 74 kW capacity. A pickup truck has been assumed to have a 55 kW capacity. According to the author’s knowledge, damaged pipelines are usually not removed from the ground. Therefore, this LCA stage has not been covered in the article.
A regression-tree-based model for mining capital cost estimation
Published in International Journal of Mining, Reclamation and Environment, 2020
Hamidreza Nourali, Morteza Osanloo
O’Hara model comes with error in most of situations, so that this model should be used only for rough estimation of mining capital cost [22]. Not considering the other effective variables in the model construction process may lead to a considerable error in results. Therefore, the multivariate regression can be considered as an alternative solution for providing a reliable cost estimation model [23]. Accordingly, a multiple linear regression model for the capital and operating cost of the backhoe loader was developed [24]. Cited models only can be used for capital and operating cost for one machine. Likewise, another multiple regression-based cost model to estimate capital and operating cost of a flotation machine was developed [25]. Most of the declared cost models were constructed to use in special cases such as estimation of a machine or a product cost.
Assessment of applicability index for better management of municipal solid waste: a case study of Dhanbad, India
Published in Environmental Technology, 2018
The DMC has 62 vehicles for waste collection and transportation including 55 tractors of 2.5 metric tonnes capacity with one driver and four to five labors for loading and unloading waste, and seven Joseph Cyril Bamford (JCB) backhoe loader for waste collection along with one driver per vehicle. The detailed information about the MSW generation rate and management infrastructure for the study area is presented in Table 2. The waste collected from various localities is directly disposed off by open dumping on low-lying areas (at the outskirts) of the city. In most of the cases, the waste is simply dumped on such sites and waste compactors are rarely used for compaction at the disposal site. There are no provisions for leachate and gas control at the dumping sites, and there is no proper closure plan of the existing landfill sites at present. The open dumping of waste is making the whole area unhygienic and posing a serious threat to the environment and health of the local people.