What is Sheep foot Roller?
A sheep foot roller is a moving machine that is used to compact the soil. This roller is unavoidable equipment used in the road construction line. It is used not only on roads but also for compacting the base foundation of buildings or other structures which have spread or shallow foundations.
Sheepfoot rollers are static and vibration types of machines used for compaction of soil with a mixture of all fine-grained clay and sand gravel. it has metal drums with luggage fixing and can pressurize up to 14 kilograms per square centimeter. there are different types of lugs such as a spindle-shaped, wide vase, prismatic, and clubfoot types.
The weight of the drum can be increased by adding water, sand or any metal mounting to it.
Types of Sheep foot Roller?
There are different types of sheep foot roller described below.
- Ordinary Sheep foot Roller
- Convertable Roller
- Turn Foot Roller
1) Ordinary Sheep foot Roller
Ordinary sheep foot roller produce good compaction throughout the thickness of the layer. These types of rollers are used where the layer is cohesive, impervious, and clay.
The roller consists of a series of hollow steel drums and grooved steel mounted on its surface. Steel grooves are around 100 mm to 200 mm apart from each other. Its weight may be up to 15 tones and travel at the speed of 25 KM/hrs.
The steel grove mounted on the drum produces extra compaction of the layer from button to top layer.
2) Convertable Roller
The Convertable roller is one that can be easily converted into an ordinary roller. There is a separable grove cover that can be easily attached or unmatched with the roller and can be used for extra compacting and smooth surfaces when required.
3) Turn Foot Roller
As their name, the turn foot roller has a turnable groove on the drum. The arrangement of grooves in the Zic Zac way helps to compact the soil under different position.
Characteristics of sheep foot Rollers
- The ground coverage area of this roller is low 8 to 12 percent.
- Ground coverage under the lugs on the drum contact pressure from 1400 to 7000 kilopascals.
- Sheep foot roller works normally at a speed of 6 kilometer to 10 kilometer per hour.
- The compaction effect of the roller depends on the kneading and the weight of the roller.
- It is mostly used for sand soils such as silky soils mother than heavy soils and sandy soils.
- The thickness of the compacting layer is kept to a minimum of five centimeters or more depending on the length of the foot uses on sheet foot rollers.
- Sheep foot rollers are used to compact fine clay and fine grain soils such as silty clay also used for the compaction of subgrade layers in freeway and rail tasks.
Advantages of sheep foot Roller
- It provides good compaction of the soil layer than another roller.
- It can be used in adhesive as well as cohesive soil.
- The needle of the groove enters into the soil to compact the lower layer of soil as well.
- It does not require more kneading effects.
Disadvantages of sheep foot Roller
- It consumes more fuel.
- It makes soil unsmooth after compaction.
- Skilled manpower is required for setting and running the machine.
Different Types of Roller
- Smooth-Wheeled roller
- Pneumatic-tyred roller
- Sheep-Foot roller
1) Smooth-Wheeled Roller
The smooth-Wheeled roller is a plain steel roller. Its weight varies from 5 tones to 15 tones. These types of rollers have one front wheel and two rear wheels. Rear wheels are of larger diameter and generally made up of rubber tyres.
The effects of compaction by a smooth wheeled roller do not reach the bottom of the layer. It can only compact the upper surface of the plot. After compaction, the roller leaves a smooth surface. These types of rollers are used to compact the granular soil like sand, gravel, and crushed stone.
2) Pneumatic-tyred roller
Pneumatic tyred roller consist of number of rubber tyres at the front and rear side of the roller. If is most suitable to compact fine graded soil. The width of tyre can be adjusted to change the impact of compaction per unit area on the layer of the soil.
3) Sheep-Foot roller
We have discussed in brief about sheep foot roller above the article. Further, these types of rollers are used where high compaction of land is required.
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