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Construction
Published in Connie Kelly Tang, Lei Zhang, Principles and Practices of Transportation Planning and Engineering, 2021
A bulldozer is a type of heavy construction machine powered by a tracked tractor and equipped with a heavy metal blade to push soil, sand, or other loose material during construction. It is one of the most common types of construction site preparation equipment. The front metal blade can be changed to different styles to fit the type of work required.
Earthmoving, Excavating, and Lifting Equipment Selection
Published in Douglas D. Gransberg, Jorge A. Rueda-Benavides, Construction Equipment Management for Engineers, Estimators, and Owners, 2020
Douglas D. Gransberg, Jorge A. Rueda-Benavides
A bulldozer is a tractor unit with a blade attached to its front. The blade is used to push, shear, cut, and roll material ahead of the tractor. It is an ideal surface earthmover that performs best at about 3 mph. Each model of bulldozer has an operating range for blade size and adjustment. Larger machines have greater operating ranges than smaller machines. A larger machine can pitch and tilt deeper than a smaller machine typically. For heavy civil work, bulldozer blade widths can range from 8ʹ to 22ʹ, and operating weights can range from about 7 tons to over 120 tons. Maximum digging depth ranges from about 1.5ʹ to 2.5ʹ.
Equipment performance and costing road construction
Published in Thompson Roger J., Peroni Rodrigo, Visser Alex T., Mining Haul Roads, 2019
Thompson Roger J., Peroni Rodrigo, Visser Alex T.
A bulldozer is a crawler (tracked tractor) equipped with a substantial metal plate (known as a blade) used to push large quantities of unconsolidated or lightly compacted soil, sand, blasted rock or other such unbound material during construction and earthworks. It is typically equipped at the rear with a claw-like device (known as a ripper) to loosen densely compacted materials. The equipment is suited for heavy tasks and can be used to handle coarse fragmented material (typically used in the base layer), cutting and filling the in-situ material to prepare and level the subgrade or even opening the material used to build the wearing course. It is a versatile piece of equipment and also central to any haul road construction project. Applicable sizes are generally in the >50 t GVM, 300 kw engine power class. Many larger bulldozers are equipped with electronic position controls that can be programmed to construct the geometric design.
Evolutionary multi-objective optimization for bulldozer and its blade in soil cutting
Published in International Journal of Management Science and Engineering Management, 2019
A bulldozer is construction equipment which has a tractor for supplying power and a metallic blade at its front for soil cutting. When the soil cutting operation is modeled for a bulldozer and its blade, an emphasis is given to make the operation economic and productive. The operation can be made economic when its variable cost can be reduced. The variable cost depends on the operating conditions which involve many parameters, such as power required from the bulldozer, the speed of the bulldozer, depth of a blade inserted in soil, dimensions of a blade, etc. The operation can be made productive when a bulldozer can finish the soil cutting operation as early as possible. However, any productive soil cutting operation with a large size blade operating at a larger speed and a higher cutting depth requires more power from the bulldozer.
Parallel machine replacement under horizon uncertainty
Published in The Engineering Economist, 2019
Javad Seif, Brett A. Shields, Andrew Junfang Yu
Consider a bulldozer that is operated 8 h/day and 300 days per year. If the useful life of the bulldozer is 24,000 h of operation, then . Increasing the utilization level from to () implies that h has been deducted from the life of the machine. Let us assume that years. Even if a bulldozer is used 24 h/day for a year, it is not possible to operate it more than h/year. Therefore, the utilization level of the machine cannot increase more than units in a year. For example, we cannot have a one-year-old bulldozer with . For a one-year-old bulldozer (), . Similarly, the utilization level (cumulative operating hours) can be at most 6 (14,400 h) for a bulldozer that is 2 years old ( for ), and it cannot be more than 9 (21,600 h) when i = 3. For older bulldozers, the cumulative operating hours cannot be greater than 24,000 h () because the assumed policy is that the useful life of the machine is 10 years, or 24,000 h of operation. All possible combinations of age () and utilization level (j) are shown in Figure 1.