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Excavators, Draglines, and Clamshells
Published in John E. Schaufelberger, Giovanni C. Migliaccio, Construction Equipment Management, 2019
John E. Schaufelberger, Giovanni C. Migliaccio
The maximum digging depth for backhoe excavators typically range from 12 to 35 feet. Very large backhoes manufactured for mass excavation work can excavate to depths up to 60 feet. The optimal digging depth for a backhoe is between 30% and 60% of its maximum digging depth. There are a wide variety of buckets manufactured, and contractors generally select bucket sizes to match job site requirements. Narrow buckets are used for trench work, while the large wide buckets are used for mass excavation. Material excavated by backhoe excavators typically is either stockpiled near the excavation site or loaded into trucks.
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.