INNOVATION May-June 2017

2016 | ❖

2017 Project Highlights

Extradose bridge spans India’s Ganges River

wide single-cell precast concrete box girder with a plane of stay cables and pylons down the median erected through balanced cantilevering. Extreme scour depths, high seismicity, fast water currents, and exceptionally large water-level variations make site conditions challenging. In addition, the construction means and methods needed to address monsoon-season fluctuations in river levels and extreme rains. Completion is expected in mid-2017. APEGBC members: David Jeakle, P.Eng., Raj Singh, P.Eng., Morgan Trowland, P.Eng., Chad Amiel, P.Eng., Gurpreet Sohal, P.Eng., Vikram Verma, P.Eng., Brook Robazza, EIT Demolition then continued over dry land where the bridge was dismantled and shipped off-site for disposal. Hatch Corporation and Mott Macdonald (civil and structural), Thurber Engineering (geotechnical), DMD & Associates (electrical), Northwest Hydraulics Consultants (hydrotechnical), B&B Heavy Civil Construction (general contractor), Reinforced Earth Company Ltd. (mechanically stabilized earth walls), Construction Drilling Inc. (pile driving), Davies Geotechnical Inc., All-Span Engineering and Consultants (temporary works, erection and demolition). (P hoto : H atch C orporation )

A new, four-kilometre-long, four-lane- highway bridge over the Ganges River, near Patna in Bihar, India, is being procured through a design– build contract. It includes the longest extradosed spans in the country, combining structural elements of both a pre-stressed box-girder bridge and a cable-stayed bridge. McElhanney is the prime consultant for the value-engineered extradosed segmental concept. This includes 16 back-to-back 120-metre-long spans that reduced construction duration and material consumption for the 1,920-metre navigation spans portion of the bridge. The extradosed superstructure consists of a 20.5-metre- The 70-year-old Keith Road Bridge in the District of North Vancouver was replaced to improve east–west connectivity across the municipality, ease traffic congestion, and support future highway improvements. The project team planned and executed the demolition of the existing lead- painted bridge to limit work above Lynn Creek, a fish-bearing stream. The entire 490-tonne steel truss was jacked up in one piece three metres above the original bearing elevations, moved laterally on sliding beams to the new adjacent bridge structure, lowered onto hydraulic dollies, and towed away. The Columbia River Skywalk, a 225-metre, clear-span suspension bridge, allows both pedestrians and utilities (water and sewer) to cross the Columbia River at Trail, BC. All-Span Engineering designed and prepared a comprehensive erection plan for the bridge’s installation and erection. Elements included a 225-metre highline and work platform for the installation of the suspension elements and deck structure, along with all cable pulling and stressing equipment.

Bridge-demolition process minimizes environmental impacts

Suspension bridge provides pedestrian and utility access across Columbia River

Comprehensive analysis of the bridge structure during all phases of the erection needed to be performed to ensure that the structure was not overloaded at any stage during construction. APEGBC members, COWI (bridge designer): Nedim Alca, P.Eng., Julie Gubbins, P.Eng.; All-Span Engineering & Construction Ltd. (erection engineer): Barry Gerbracht, P.Eng.; Graham Infrastructure LP (contractor)

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