RITES Ltd., invited Sealed Tenders in single packet system from experienced, technically and financially sound reputed firms in Geotechnical Investigation including Drilling of boreholes for the following work: – Geotechnical Investigation of Tunnels, Yards, Formation, Major Bridges in connection with execution of Doubling of Railway line in between Tikiri-Bhalumaska (45.86km) stations of KR line in East Coast Railway.
- Tender Reference Number: RITES/RCED/ECoR-T-B Section/GT Inv/2021
- Name of Work: Geotechnical Investigation of Tunnels, Yards, Formation, Major Bridges in connection with execution of Doubling of Railway line in between Tikiri-Bhalumaska (45.86km) stations of KR line in East Coast Railway.
- Document Download / Sale Start Date: 19-Oct-2021
- Document Download / Sale End Date: 08-Nov-2021
- Bid Submission Start Date: 19-Oct-2021
- Bid Submission End Date: 08-Nov-2021
- Bid Opening Date: 09-Nov-2021
- It is proposed to carry out drilling of boreholes at specified locations for the formation, yards, major bridges and tunnels up to required depth (Maximum 70m) in all type of formation i.e. soil/boulder/rock, conducting SPT, in-situ permeability tests etc., collection of Undisturbed/Disturbed soil samples, rock in connection with doubling of Railway line for all three packages of Section Tikiri-Bhalumaska (45.86Km) stations of KR Line in East Coast Railway including submission of Field and Computer generated Bore hole Logs/ Geological Logs for following packages.
|Section Details||Approx. number of BHs||Estimated cost (Rs)||Package|
|Total Estimated Cost||1,18,71,850|
Scope of Work:
The scope of work includes the following:
- Mobilization, demobilization of drilling rig, other drilling tools and accessories including personnel for carrying out Geotechnical investigation work.
- Exploratory drilling of Boreholes down to required depth (upto 30m), drilling of 150mm diameter boreholes in all type of soils except hard rock and large boulders (boulder core more than 30 cm), including refilling and reinstating surface, and disposing off surplus material by using appropriate/suitable drilling machine capable for advancing through occasional seams of hard strata to be employed, where necessary in Dry area.
- Drilling of NX size borehole (75 mm dia) in all types of hard rock (fresh rock) up to 70m depth by using appropriate/suitable drilling machine capable to drill through hard rock comprising Quartzo-feldspathic granitic rock and collection of rock core samples from boreholes and preserving in boxes.
- Conducting standard penetration Test – The standard penetration test shall be conducted in all bore holes at specified interval as per the general specification suggested by IS code of practice. SPT shall be terminated on recording 100 blows per 30cm or less penetration. The disturbed samples obtained from the split spoon sampler shall be visually classified, labeled for identification and preserved for laboratory testing.
- Collecting undisturbed soil samples- Taking out undisturbed samples of soil from bore holes, including provision of air tight containers for packing and, labelling incl. transporting the samples to laboratory.
- Piston sampler shall be used for extracting undisturbed samples where necessary. Samples shall be collected as per IS 2720.
- Collecting disturbed soil samples- Taking out 100mm dia & 450mm long disturbed samples of soil from bore holes, including provision of air tight containers for packing, labelling and transporting the samples to laboratory.
- Samples shall be collected as per IS 2720. Collection of water samples. The scope also includes collection of water samples as per IS codes.
- Conducting Permeability Test: In-situ permeability test in bore hole at Tunnel and bridge sites at desired depth as per I.S. 5529 (part – II for rock) (1983) using single/double packer. Submission of Geological logs as per the format issued by Engineer-in-charge in hard and soft copies.
Field Investigations – in Soil:
- Boreholes shall be taken at specified locations to obtain information about the sub- soil profile, its nature and strength and to collect soil samples for strata identification and conducting laboratory tests. The minimum diameter of the bore shall be 150 mm and boring shall be carried out in accordance with the provisions of IS: 1892 as per this specification.
- All bore holes shall extend up to depths as directed by the Engineer. If the strata with Standard Penetration Test (SPT) `N’ value greater than 100 with characteristics of rock is met with, prior to the specified depth, the bore hole shall be advanced further by chiseling. Chiseling shall be continued for a maximum depth of 20 cm or up to 2 hours whichever is earlier. During chiseling rock fragments shall be collected. Identification of rock strata shall be on the basis of visual examination of SPT sample and rock fragments.
- Casing pipe shall be used in the borehole to support its sides when a side fall is suspected to occur inside the borehole. When casing pipe is used, it shall be ensured that its bottom end is at all times less than 15 cm above the bottom of the borehole and not below the level at which the test has to be conducted or sampling has to be done. In case of cohesion less soils the advancement of the casing pipe shall be such that it does not disturb the soil to be tested or sampled. The casing shall be advanced by slowly turning the casing pipe and not by driving.
- In-situ tests shall be conducted or undisturbed samples (UDS) shall be collected in the bore holes at regular intervals and at change of strata or as decided by the Engineer. Representative disturbed samples shall be preserved for conducting various identification tests in the laboratory. Water table in the borehole shall be carefully recorded and reported. No water /drilling mud shall be added while boring above ground water table.
- The bore hole shall be cleaned using suitable tools up to the depth of testing or sampling, ensuring that there is minimum disturbance of the soil at the bottom of the bore hole. The process of jetting through an open tube sampler shall not be permitted. In cohesive soils, the bore hole may be cleaned using a bailer with a flap valve. Gentle circulation of drilling fluid shall be done when rotary mud circulation boring is adopted.
- During drilling, depth of water table, joint set, joint Nos. should be recorded.
Rotary Mud Circulation Boring:
- This method can be used in all types of soil below the water table. In this method boring shall be done by rotating the bit fixed at the bottom of the drill rod.
- Proper care shall be taken to keep firm contact between the bit and the bottom of the bore hole. Bentonite mud shall be used as the drilling fluid to prevent caving in of the bore hole sides.
- Use of percussion tool shall be permitted in hard clays and dense sandy deposits.
Tender documents may be downloaded from CPPP website https://etenders.gov.in/eprocure/app and from RITES website https://www.rites.com.
Source: RITES-Tender | Image Credit (representational): MoR
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