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| 1 | The work includes fabrication, supply, testing, and installation of a heavy-duty Mild Steel (M.S.) stop log hanger/lifting beam assembly for the weir-side gates of the barrage, to be manufactured strictly as per the dimensions, design data, material specifications, load capacity, UTS, YS, allowable bending and shear stresses, and self-weight (583.52 kg) of the existing approved hanger, for which complete drawings and design details of the existing hanger are available with the department and attached with the estimate. The main lifting beam shall be fabricated from two ISMC 300 sections rigidly connected with M.S. plate batten plates at regular intervals, with a total length of 18.00 m and two hook gaps of 10.00 m suitable for engagement with the gantry crane sheave block through M.S. locking pins, identical to the existing arrangement. All fabrication shall be carried out using structural-grade M.S. conforming to relevant IS standards, including precision cutting, drilling, edge preparation, continuous welding, grinding, fit-up, alignment, and inspection, with all welded joints visually examined and tested for proper bonding and structural integrity. After fabrication, the entire assembly shall be abrasive blast cleaned to surface finish SA 2.5 and coated with one coat of epoxy zinc-rich primer followed by two coats of high-build epoxy coating to achieve a minimum total dry film thickness (DFT) of 400 microns suitable for submerged and humid barrage conditions. The contractor shall arrange material testing at a DJB-approved laboratory and shall carry out complete load testing at site with five times the safe working load to verify structural performance as directed by the Engineer-in-Charge. This item includes all operations such as material procurement, fabrication, reinforcement, welding, machining, surface preparation, epoxy painting, transportation, site handling, installation, erection, final alignment, testing, certification, labour, machinery, tools, and all incidental works required for completing the job in all respects to the satisfaction of the Engineer-in-Charge |
| 2 | Fabrication, Supply, and Fixing of Stop Log Gate / Hanger Resting Boom Stand on Barrage Pier (Weir Side)The work includes fabrication, supply, and installation of stop log gate/hanger resting boom stand on the top of the barrage pier (weir side) as per site requirements and departmental directions. A base plate of M.S. (Mild Steel) size 380mm × 380mm × 25mm thick shall be anchored and fixed over the top of the pier, using 4 Nos. high-tensile bolts of 30mm diameter and 760mm length, complete with nuts and washers. The fixing shall involve core cutting of the existing civil structure of the pier using mechanical cutting machines, and chemical anchoring shall be carried out using approved high-strength structural-grade chemical adhesive. The bolts shall be integrated with the existing reinforcement of the pier through welding and the addition of extra steel reinforcement bars to ensure proper load transfer and enhanced structural strength.A main M.S. plate of size 355mm × 150mm × 20mm thick shall then be fabricated and installed over the base plate, supported by three Nos. of 150mm × 150mm × 20mm thick plates and one plate of size 405mm × 125mm × 20mm thick, forming a movable assembly capable of opening and closing operations for hanging and removing stop logs and hangers.The complete stand shall be designed and fabricated to safely sustain a maximum load of 6.5 tonnes, considering wind pressure, storm, and heavy rainfall conditions on the barrage structure.The hanger resting boom stand shall be fabricated exactly identical to the existing stands already installed on other piers for uniformity and compatibility. After installation, each stand shall be load tested by placing the existing weir side stop log gate and applying an additional test load of 2000 kg, to be performed a minimum of five times on separate days under varying wind conditions to ensure long-term safety and performance. For safe execution of the work, scaffolding and working platforms shall be erected around the pier to facilitate welding, cutting, drilling, fixing, and hammering operations by expert and experienced labour, ensuring complete safety while working over deep water conditions of the barrage pond. All fabricated steel surfaces shall be cleaned, surface-prepared, and finished with After fabrication, the entire hanger shall be abrasive blast cleaned to surface finish grade SA 2.5, followed by application of one coat of epoxy zinc-rich primer and two coats of high-build epoxy coating, providing a total dry film thickness (DFT) of not less than 400 microns coating) for effective corrosion protection under submerged and humid barrage conditions.specifications and directions of the Engineer-in-Charge.(This item includes all works such as fabrication, cutting, welding, drilling, anchoring, scaffolding, chemical fixing, reinforcement strengthening, alignment, and multi-stage load testing for the complete and safe installation of the stop log gate/hanger resting boom stand on the barrage pier.) design drawing enclosed) |
| 3 | The work involves refixing of a Mild Steel (M.S.) base plate of size 380mm × 380mm × 25mm thick over the top surface of the barrage pier. The base plate shall be further strengthened with the provision of two high-tensile bolts of 30mm diameter and 760mm length, complete with nuts and washers to ensure robust anchorage and stability. The fixing operation shall include core cutting of the existing pier structure using precision mechanical cutting machines, followed by anchoring with an approved heavy-duty structural-grade chemical compound. The anchor bolts shall be integrated with the existing pier reinforcement through welding and the addition of supplementary reinforcement bars to enhance load-bearing strength and overall structural integrity.The main M.S. plate, earlier of size 255mm × 150mm × 20mm, shall be replaced and upgraded to 355mm × 150mm × 20mm thick, providing an enlarged resting surface for the stop log, ensuring improved operational efficiency, safety, and stability during lifting and lowering operations. The main plate assembly shall be supported by three M.S. plates of size 150mm × 150mm × 20mm thick and one M.S. plate of size 405mm × 125mm × 20mm thick, collectively forming a movable mechanism capable of opening and closing movement for hanging and releasing stop logs and hangers with precision alignment.The renovated hanger resting boom stand shall be designed, fabricated, and installed to safely withstand a maximum load of 6.5 tonnes, taking into consideration wind pressure, storm effects, and heavy rainfall conditions acting on the barrage structure. The resting plate shall be extended as required to provide safe footing and working access for maintenance personnel during operation, inspection, and emergency conditions.All fabrication, assembly, and fixing works shall be carried out to match the existing boom stands already installed on adjacent piers, ensuring uniformity in design, alignment, and appearance across the barrage structure. After fabrication, the entire hanger shall be abrasive blast cleaned to surface finish grade SA 2.5, followed by application of one coat of epoxy zinc-rich primer and two coats of high-build epoxy coating, providing a total dry film thickness (DFT) of not less than 400 microns coating) for effective corrosion protection under submerged and humid barrage conditions.Upon completion, each renovated boom stand shall undergo load testing using both weir-side and under-sluice stop log gates, along with an additional test load of 2000 kg. The testing shall be conducted at least five times on separate days under varying wind and flow conditions to verify durability, performance, and long-term stability of the installation.For safe execution of renovation works, appropriate scaffolding and working platforms shall be erected around the pier, enabling welding, cutting, drilling, dismantling, and refixing operations to be carried out safely and efficiently by qualified and experienced technical personnel, taking into account the deep-water and high-flow conditions of the barrage pond.(design drawing enclosed). Please Enable Macros to View BoQ information |
