2023-12-06

Funding Agency: Japan International Cooperation Limited (JICA)
Client: CTI Engineering International Co. Ltd.
Date:  August 2021 – October 2021

Japan International Cooperation Agency (“JICA”) has funded to conduct “Data Collection Survey on the Sindhuli Road Capacity Enhancement in Nepal”. This Geo-Technical Data Collection Survey on the Sindhuli Road Capacity Enhancement in Nepal is part of that project Study that requires undertaking Site Reconnaissance and Electrical Resistivity Tomography (ERT) along the selected tunnel alignment in Section II of Sindhuli Road. The investigation shall be conducted to obtain geological and geotechnical information for planning of tunnel and road.

Overall Services provided:

TMS provided local logistics and project management support. Services being provided by TMS were in the areas of hydropower design, geological works, and social development.

1.  Preparation of the Work Plan for Geotechnical Investigation
2. Site Reconnaissance

• The Local Consultant shall carry out the site reconnaissance to create the geological map (S=1:10,000) of the area shown in Figure-1.
• Site reconnaissance shall be carried out in order to confirm or estimate, 1) the location of Main Boundary Thrust (MBT) and Mahabharat Thrust (MT), 2) the scale and conditions of trusts and their share zones, 3) the rock condition of the site
• In the site reconnaissance, the location of MBT and MT, and their share zone (if available) shall be identified based on the actual topographic conditions, actual distribution of geological units and rock conditions, i.e., distribution of kerncol and/or kernbut, distribution of formations of Siwalik Group and the Benighat Slates of Upper Nawakot Group, etc. or alike.
• In case it is difficult to identify the location of MBT and MT and/or geological boundaries based on the site reconnaissance in the mapping area, the Local Consultant shall check the topographical and geological conditions of outside of the mapping area.
• The site reconnaissance shall be conducted by an experienced geologist (responsible person: not less than 10 years on geological site reconnaissance, other members: not less than 5 years).
• The location of MBT and MT and their share zones shall be described in the geological map and longitudinal section of ERT results.
• The rock conditions shall be checked by Rock Mass Rating (RMR) at the site and data sheets shall be submitted. In the RMR checking, the value for “Rating Adjustment for Discontinuity Orientations” shall be “-5” of tunnels and mines in all of the cases.
• The water flow rate of the streams and/or springs shall be checked visually and recorded (unit: 1/min).
• The location of faults, geological boundaries, share zones, outcrops, dips, strikes, water flow rate, photos, etc. shall be described in the geological map (S=1:10,000)
• Digital topographical data (CAD file) for the base geological map will be provided by the JICA Study team.

3. Electrical Resistivity Tomography (ERT)

• The Local Consultant shall conduct Electrical Resistivity Tomography (ERT) at the site as shown in Figure-1 or as directed by the JICA Survey Team.
• The Local Consultant shall submit “the resistivity tomograms and interpretative section” as a result of the tests.
• The ERT shall be conducted under the following conditions
• Digital topographical data (CAD file) will be provided by the JICA Study Team and the Local Consultant shall prepare the topographic profile from this data.