root pile construction
root piles formation

Root piles are heaps of very small diameter (usually 60 mm to 135 mm). The length of the root pile generally varies within 4 m to 30 m.

The concept of root heap was first introduced by a. was introduced by italian engineer Nominated f lizzy, His primary concern behind the development of the root pile was to act as the underpinnings. Nowadays, root piles are also used for slope protection work, where a network of root piles is created to protect the slope. it is called reticulated root hemorrhoids, Root piles are also used for landslide correction.

Root hemorrhoids should not be confused with microscopic hemorrhoids. In case of micro piles, steel pipe is used whereas in case of root piles a single steel bar is used.

Root piles manufacturing process

step 1 (hole drilling)

Drill a hole approximately 100 mm in diameter, with or without a drill pipe. The diameter of the holes can be changed according to the soil condition or requirements of the site. Drilling is done by rotary drilling method and is advanced by direct movement of water or bentonite slurry. In the method of direct circulation, the cut pieces formed due to the cutting action of the bit are brought to the surface with bentonite or water.

step 2 (by placing the reinforcement bar)

After completing the drilling operation to the required depth, install a reinforcement bar of dia. About 15 mm or more. Then install a tremie pipe inside the drill pipe. Tremi pipe is used for applying mortar.

step 3 (filling mortar)

Fill the hole with a cement sand mortar of 600 kg to 800 kg of cement for one cubic meter of sand. This type of mortar gives high strength. The mortar is held in place by tremie pipe and filled from bottom to top. At any time during placing or mortaring, the lower end of the tremie pipe must be inserted into the mortar to be laid.

step 4 (drill pipe removal and pressure application)

The process of grouting is done in stages by dividing the length of the grout into smaller sections. This is done to adjust the grout volume and injection pressure according to different soil conditions. At each stage, an air pressure of not more than 60 kg/m2 is applied to the top of the drill pipe and the tremie is slowly withdrawn. Air pressure makes it easy to retract the pipe and improve contact with pile soil.

Step-5 (end of stack)

After removing the drill pipe completely, release the air pressure and allow the mortar to set.

Er. Mukesh Kumar

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Er. Mukesh Kumar is Editor in Chief and Co-Funder at Civil Engineering Website. Mukesh Kumar is a Bachelor in Civil Engineering From MIT. He has work experience in Highway Construction, Bridge Construction, Railway Steel Girder work, Under box culvert construction, Retaining wall construction. He was a lecturer in a Engineering college for more than 6 years.