Figure 10 Contract management of Padma Bridge Project
Related Figures (13)
Figure 1: Location of Padma Bridge adopted from Islam et al., (2011) To design the Main Bridge and RTW, the Bangladesh Bridge Authority (BBA) hired AECOM, Hong Kong, NHS, Canada, and SMEC, Australia. Before carefully considering a variety of bridge shapes, AECOM conducted a thorough evaluation of the prior works designed for the Figure 2: Gas pipeline and telecommunications cables in Padma Bridge (Padma multipurpose bridge project, 2022) Figure 3: Record-breaking works of Padma Bridge Project (Padma Multipurpose Bridge Project, 2022) Figure 4: Technical details of Padma Bridge (Business Insider Bangladesh, 2022) The Padma Bridge's superstructural loads are supported by 294 piles in total. There are 365 bored piles altogether among the 1.2 m diameter vertical bored piles in viaducts, with 172 in Mawa and 193 in Janjira. The piles are 150 meters long, making them the deepest piles ever used in a bridge (Sham ef al., 2010). German engineers employed the largest hydraulic hammer in the world, with a 3,000- kilojoule capacity, to drive those piles (De Silva et al., 2013). The piers are covered with steel spans. In total, the bridge has 41 spans. Upper deck and lower deck are the two decks that make up the spans. The bottom deck features a single-track dual gauge rail, and the upper deck is made up of a 21.65 m wide concrete deck slab with a four-lane roadway. The deck has a 13.6 m height and 18.3 m of clearance was maintained for navigation. The speed restriction for cars on the route is 60 km/h, whereas it will be 160 km/h for trains. The bridge is anticipated to last for about 100 years in total. Figure 6: Research methodology of this critical review study A steel truss bridge with a concrete top slab can have steel weights of up to 3,200t per truss, and when the concrete decks are added, the weight increases to 8,600 t. Nodes and chords of each truss were constructed in China using steel plates that ranged in thickness from 40mm to 120mm (Tian et al., 2021). The nodes and chords were combined and welded into the final 3D shape at the Mawa construction yard. 60mm thick steel plate (Figure 7). A 70-meter-long bottom part and a roughly 50-meter-long top section were created for each pile by combining 3.2-meter-long pile components. Full penetration welding was used to link each pile segment. After welding, a non-destructive test (NDT) was performed on the pile's inside and exterior. Visual inspection and ultrasound testing were used for NDT testing. Some samples of the welded plates were taken for laboratory tensile tests, bending tests, and impact tests (De Silva et al., 2013). Pile was propelled by MENK hammers with 1,900, 2,400, and 3,500 kJ capabilities. The manufacture of the 262 piles required a total of 155,779 mt of steel plate (Muhaimin et al., 2021). A unique pile foundation design that consists of six floating heaps and one center pile with the largest raking pile in the center were both utilized to resolve the geotechnical challenges. Raking steel tube-driven piles with a 1:6 inclination were used as the Main Bridge Piles. There are 6 piles on 18 piers and 7 piles on 22 piers. Out of 22 piers, 7 piles on 11 piers have skin grouting, and the remaining 7 piles on the other 11 piers don’t have that. Pile lengths range from 98 to 125 meters, with the longest- driven tubular pile in the world measuring 125 meters. 124.6MN is the maximum pile capacity (Islam, 2016). The 3m exterior diameter steel tube piles are made from a Figure 8: Padma Bridge Project Construction Processes Figure 9: Dumping of Geobags on the lower slope underwater slope and in the launching apron). 600 kg of rice bags, 125 kg, and 800 kg of geo-bags were placed within the scour holes (Figure 9). Figure 13: COVID Protocol issued during Padma Bridge Construction and there were no injuries because of rigorous adherence to the COVID guidelines and restrictions on people's movement (Lotfi et al, 2022). This made it easier for the project to continue operating. Figure 12 shows specifics of COVID safety precautions taken during Padma Bridge building. However, the project work advanced somewhat slowly since the material supply chain was hampered.
