“Geotechnical investigation is a big challenge as it is very important to know the exact soil condition for foundation engineering. There are different types of erogenous soil conditions in the Himalayan region, posing a challenge to contractors. We have done a project in Nepal and are doing a very prestigious tunnel project of RVNL in Rishikesh using a masterpiece of Casagrande PG185 having dual power (electric & diesel unit) to construct Horizontal Jet Column of 18m length of 600mm 450mm Dia.
The tunnel, which will connect Rishikesh and Karanprayag for the Char Dham Yatra, is one of the longest at 125 km consisting of 106 km of tunnel and 35 numbers of flyovers. Our machines are built to work in temperatures ranging from 50 degrees to minus 30 degrees.”
“There are a lot of projects in the pipeline, so we are optimistic that a lot of upcoming opportunities will come our way, more so in view of Budget FY23-24 that has placed a lot of emphasis on growing the infrastructure and construction industry. Our aim is to bring environmental-friendly new technologies that improve productivity, and efficiency. We see electric-driven machines as the future of the construction industry.”
Casagrande takes pride in selling its equipment in more than 90 countries, including India. It has service centers in Delhi, Mumbai, Chennai and Ahmedabad and centers for stocking spare parts in different regions of the country.
Horizontal Jet Columns in Tunnel for Excavation Support System by Casagrande Rig PG185
- Project: Rishikesh – Karanprayag Rail Link Project – Package 1
- Client: RVNL
- Contractor: Max Infra Limited
- Consultant: Lombardi – Italferr JV
- Equipment: Casagrande PG185 + Techniwell High Pressure Pump + Jean Lutz System
- Horizontal Jet Column: 600mm and 450mm dia and 18m depth
Casagrande’s expertise was evident in India’s prestigious tunnel project - the Rishikesh – Karanprayag Rail Link, which is under construction by RVNL The tunnel will connect Rishikesh and Karanprayag for the Char Dham Yatra and will be a boon for the local residents. At 125 km, it is one of the longest tunnel rail link project, spanning 106 km of tunnels and 35 flyovers. Rishikesh, which is located on the foothills of the Himalayan range, has a challenging geology consisting of loose sand, soil, clay, gravel, and boulders.
In Package 1 of this project where Max Infra is the contractor and Lombardi – Italferr is the consultant, some sections of tunnel are being constructed using Horizontal Jet Columns as excavation support system. To construct the Horizontal Jet Columns Casagrande supplied the following equipment:
- Casagrande PG185 Forepoling Rig
- Techniwell High Pressure Pump
- Jean Lutz Instrumentation System
The width and height of the Escape Tunnels is 5.2m each.
Horizontal Jet Columns of 600mm dia and of 18m length are constructed on the Crown Periphery of both the tunnels.
Jet Columns of 450mm dia and of 14m length are constructed on the face of the tunnel.
A masterpiece of Casagrande – the PG185 - has dual power (electric & diesel) has been employed at this tunnel project to construct Horizontal Jet Column of 18m length and 600mm 450mm dia. PG185 is radio controlled and designed, based on a mechanism that involves mounting a highly maneuverable hydraulic base carrier (a long horizontal mast) supported by two telescopic columns that permit the angle of inclination of the mast to be set to the alignment of the tunnel. These two telescopic columns are mounted on ring gears that allow 180°.rotation of the mast.
Construction of the Jet Columns is executed in two phases, one of which is the drilling phase. At the jobsite, drilling is executed with single fluid drill rods of 89mm up to the depth of 18m in single stroke.
In the second phase called Jetting, single fluid drill rods are extracted in a controlled manner. The RPM of the rods is set at 15rpm and rods of 18m length are extracted in single stroke, while a high-pressure grout of approx 400 bars is pumped through the rods to create a jet column of 600mm and 450mm and dia of 18m length.
Jean Lutz instrumentation is connected to the PG185 that controls, monitors, and records all the drilling and jetting parameters during construction of the Jet Columns.
Trial Jet Columns were executed at a location near the Main Tunnel jobsite. The dia of each trial Jet Column is measured and its Jetting parameters are recorded. The strength of each Jet Column is also measured.
Jean Lutz system helps in monitoring and recording all the jetting parameters for each jet column, including the following:
- Lifting speed of Rod
- Rotation of Rod
- Grout pressure
- Grout flow
PG185 is accompanied by a compact Tecniwell unit TW4020 - a high-pressure pump integrated with a mixing plant inside a single 20-ft container. The pump is fed by a Horizontal Silo of 50T of Tecniwell. Both the Tecniwell pump and silo are electric driven and are mounted on a trailer for easy movement during work inside the tunnel. Jean Lutz instrumentation records the high-pressure grout that is pumped from the Techniwell high pressure pump during the jetting phase.
Casagrande India is proud to claim that the PG185 deployed at the RVNL project in Rishikesh is the first in India to construct Horizontal Jet Columns in a tunnel project in India.