Thursday, March 13, 2014

Highway Excavation Equipment

how you doing? Today I am going to post here what I learnt about the highway construction equipment.

As we know that highway construction at field can be broadly classified into two phases:

  1.  Excavation or preparation of sub-grade.
  2. Pavement layers construction.
In the phase of the excavation or preparation of the sub-grade we need two types of equipment:
  1. Excavation equipment
  2. Compaction equipment
In this post I will discuss the excavation equipment. Types of excavation equipment that is to be used depends upon the type of the soil and availability of the equipment. Various equipment used in general for the excavation of the sub-grade are
  1. Bull Dosser
  2. Scraper
  3. Power Shovel
  4. Drag-line
  5. Clam-shells
  6. Hoe
  • Bulldozer 
Bulldozer is a crawler equipment used to push and haul the earth material up a distance of 100 m using its front blade and a ripper attached at its rear.
Bulldozer (source: wikipedia)

 Bulldozer is a versatile equipment because it can be used in undulating ground or level ground, can be used for various building construction projects including pilot road constructions or even in farms.
  • Scraper: Scraper is having a blade in its rear part which is used to scrap the earth and then to store it in the bowl. Once the bowl is full the loose earth can be hauled to the deposition site. There is an elevator arrangement for the blade which can elevate or lower the blade according to the need.
  • Scrapper (Source: Google images)
  • Power Shovel: Power shovel is a power equipment used to dig the earth material at lower depths than the standing elevation. The parts of a power shovel are crawler mounting, cab, boom, shovel and hoist cable.
    Power Shovel (image Source: wikipedia)
    Power shovel can be used to excavate the loose earth material effectively and can  be used in undulating grounds because it has a crawler mounting.
  • Drag-Line: Drag line has a bucket suspended from the book which can be dragged with a drag cable and hoist cable to collect the loose material inside the bucket. 
    Drag Line (Image source: wikipedia)
    Image shown above shows a drag-line with all its major parts. Drag line can be used to collect the loose material from a much larger depths.
  • Clam-shell :
Clam-shell bucket is combination of two shells which are joined together with hinges at top and when these half are closed form a bucket. It is attached to a cable and a boom arrangement and to lift the material it is made to fall on it and then lifted up. In the lifting operation clam-shells close them up and will lift the material filled inside.

  • Hoe: Hoe can be used to excavate relatively stiffer earth from a depth below the standing level of the equipment. This material can excavate all types of earth materials except hard rocks.

Thanks for your kind visit!

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