Regional Report: DFI India Dr. K.S. Rama Krishna, Head- Foundation & Geotechnical Engineering Cell (FGEC) Larsen & Toubro Ltd. Chennai, India DFI participated in the Indian Geotechnical Conference, IGC2011 held at Kochi, India in December 2011. DFI President Jim Morrison came from the U.S. to attend the conference, and representing one of the conference spon- sors, was invited to address the delegates. He gave an excellent overview of DFI activities and how DFI can contribute to the growth and development of the Indian deep foundation industry. The conference organizers provided a special session in which the president of the Indian Geotechnical Society (IGS), Prof. K.S. Rao, and Morrison shared the platform and conducted an interactive session with the delegates. The outcome of the session was that IGS and DFI can collaborate and complement each other in promoting the Case Study-1: Fast-Track Driven Piling at Mundra This case study shows how a well- planned and coordinated driven piling job enables installation of a large number of piles in a short duration, an important point for a fast developing country like India where driven piles should be preferred to bored cast-in- situ piles, where possible, to accelerate construction. Driven cast-in-situ (DCIS) piling was used to support a crude oil storage facility near the Mundra port town at Gujarat for HPCL-Mittal Pipeline Limited. Engineers India Limited was the project consultant and the entire execution was carried out by ITD Cementation India Limited, Mumbai. The facility comprised 22 tanks supported on 8,809 DCIS piles 560 mm (22 in) in diameter and 15 m (49.2 ft) long, giving a capacity of 110 MT (242.5 kips). The quality assurance scheme included 37 vertical compression load tests, 36 lateral load tests, 14 pull-out load test and 850 low- strain pile integrity tests (PIT). The driving and extraction of the pile casing tube was carried out with an indigenously manufactured pneumatic hammer weighing 5.4 tonnes (6.0 tons) mounted on a 75 tonne (82 ton) crawler crane for easy mobility. Eight such sets of driving equipment were deployed along with air compressors, batching plants, transit mixers, etc. The cycle time for the initial piles Driven cast-in-situ piling near Mundra port town at Gujarat ranged from 1 to 1.5 hrs per pile. With this initial assessment and further streamlining of operations, a drastic reduction in cycle time was possible, which resulted in the completion of 8,809 piles in just 179 days, well ahead of schedule. Some of the achievements are listed below: • Maximum Piles Installed in one day: 211 • Maximum Piles installed by a single rig in one day: 40 • More than 100 Piles installed in a day: 44 times • Maximum piles in a week: 1,042 • Maximum piles installed in one month: 3,301 • Maximum quantity of installed piles in one month 48,360 m (158,621 ft) professional practices in the Indian deep foundation industry. It was decided to hold another DFI conference in India in September, 2012, possibly in conjunction with IGC 2012, an annual geo- technical conference organized by the IGS, however subsequently it was decided to hold a standalone conference at IIT Madras, September 17-20 (see page 33). Other collaboration is being explored between DFI and IGS. Turning to the developments in the Indian deep foundation industry, we see that several Indian cities are going ahead with plans to implement Metro Rail Projects. Every geotechnical engineer would be happy to see the deployment, along the proposed routes, of state-of-the-art foundation equipment, such as hydraulic rotary piling rigs for installing bored cast-in-situ piles as foundations for the piers, trench cutters/hydro mills and hydraulic Kelly grabs for constructing diaphragm walls for the underground Metro stations and for launching the TBMs for the rail tunnels. Further, efforts underway to replace four to six 1,200 mm (47.2 in) diameter bored cast-in-situ concrete piles per pier with a single 2,400 mm/2,500 mm (94.5 in/98.4 in) diameter monopile of the same type. This would speed up construction and require a lot less space for construction around each pier, thus minimizing congestion along the busy city roads. DEEP FOUNDATIONS • JULY/AUG 2012 • 19
