In road construction, transportation of materials, manpower and equipment are of primary importance. For the execution of construction activities within the definite time frame and within the allocated budget, supply and transportation of manpower, materials and tools is required to be done. For the hauling of excavated earth materials from the roadside, transporting equipment are required. For the transportation of manpower, materials and tools from one location to another various types of machinery are used, which are known as transporting equipment. The various types of transporting equipment are as follows:
1. Tipper/Trucks
A tripper truck is the vehicle which is used to transport the various materials, equipment, and manpower within the site from one location to another location. Trucks are available in the different varying sizes. Transportation of cement, sand aggregates, sub base course materials, base course materials, bitumen, kerosene oil, diesel at the location of activities at site requires trucks or trippers. The excavated materials from one location to the dumping site of filling area is also required to be transported by using trippers or trucks. In construction, loading of materials in to tripper can be done with loader or backhoe loader as per requirement and dumping is done by raising the boom of tripper at the dumping location. There may require, due care during loading and unloading of the materials. The trippers and trucks are moved according to direction of site supervisors. The capacity of trippers/trucks are based on tonnage carrying capacity, – 31 Ton) tipper trucks are categorized into Light (2 Ton – 16 Ton), Medium (16 Ton and Large (31 Ton – 45 Ton) tipper trucks respectively. Of these categories, medium tipper truck segment is high demand among the construction industry. The volume of bucket of tripper’s ranges from 2 cum to 16 cum.
2. Concrete mixture truck
Concrete transport trucks are used to mix concrete and transport concrete to the construction site. They can be charged with dry materials and water, with the mixing occurring during transport. They can also be loaded from a central mix plant. With this process, the material has already been mixed prior to loading. The concrete mixing transport truck maintains the material’s liquid state through agitation, or turning of the drum, until delivery to the construction site. The interior of the drum on a concrete mixing truck is fitted with a spiral blade. In one rotational direction, the concrete is pushed deeper into the drum. This is the direction the drum is rotated while the concrete is being transported to the building site. This is known as charging the mixer. When the drum rotates in the other direction, the Archimedes’ screw-type arrangement discharges, or forces the concrete out of the drum. From there it may go onto chutes to guide the viscous concrete directly to the job site. If the truck cannot get close enough to the site to use the chutes, the concrete may be discharged into a concrete pump, connected to a flexible hose, or onto a conveyor belt which can be extended some distance (typically ten or more meters). A pump provides the means to move the material to precise locations, multi-floor buildings, and other distance-prohibitive locations. Buckets suspended from cranes are also used to place the concrete. The drum is traditionally made of steel but on some newer trucks, fiberglass has been used as a weight reduction measure. Concrete mixers generally do not travel far from their plant, as the concrete begins to set as soon as it is in the truck. Many contractors require that the concrete be in place within 90 minutes after loading. If the truck breaks down or for some other reason the concrete hardens in the truck, workers may need to enter the barrel with jackhammers.
3. Truck cranes
Cranes are used to transport loads over variable (horizontal and vertical) paths within a restricted area and when there is insufficient (or intermittent) flow volume such that the use of a conveyor cannot be justified. Cranes provide more flexibility in movement than conveyors because the loads handled can be more varied with respect to their shape and weight. Cranes provide less flexibility in movement than industrial trucks because they only can operate within a restricted area, though some can operate on a portable base. Most cranes utilize trolley-and-tracks for horizontal movement and hoists for vertical movement, although manipulators can be used if precise positioning of the load is required. The most common cranes include the jib, bridge, gantry, and stacker cranes.
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