The Benjamin Sheares Bridge Caused by Boring Works Below the Sea Level

AT WORK Benjamin Sheares Bridge

NET monitor movement affecting the Benjamin Sheares Bridge caused by boring works below the sea level

NET monitor perfectly even in the harshest of conditions

Opened in 1981, the Benjamin Sheares Bridge is the The Marina Bay Bridge across Marina Bay was officially longest bridge in Singapore, spanning 1.8km. It is also opened on April 24, 2010. There are two components to the tallest, at 20m. The bridge was named to honor Dr. the new bridge – a six-lane roadway for vehicle sand a Benjamin Henry Sheares, the second president of the six-meter-wide curved pedestrian connection that Republic. Built over reclaimed land, the bridge is made of overlooks Marina Bay. The spiral-shaped pedestrian pre-stressed concrete and links East Coast Parkway on bridge, called the Helix Bridge, is 280m long, while the to Marina Bay on the west coast. Bayfront Bridge, spanning 303m, was picked for the parallel bridge for vehicles.

The Bayfront Bridge provides a direct connection between Marina Centre and Marina South. The opening of this new road network will provide vehicular access to the upcoming developments in the Marina Bay area, such as the Marina Bay Sands Integrated Resort Gardens by the Bay and the Marina Bay Financial Centre. water of Singapore River; plus, power consumption of all equipment used must be kept to a bare minimum due to Monitoring Solution Providers Pte Ltd, (MSP), was the lack of constant power supply. involved in monitoring the movement of the Benjamin Sheares Bridge and later, the Bayfront Bridge under Land This project was the first use of NET for bridge movement Transport Authority Contract 905.* monitoring in severe environmental conditions. They have few worries about the lifespan of the instrument and how *Contract 905 is for the design, construction and completion of tunnels between Promenade Station and Marina Bay. often it will break down, to troubleshoot the instruments. To reach the instruments, workers had to hire a boat to To carry on the project, MSP was requested to overcome reach the pile cap where the instruments are installed. It severe conditions: the monitoring instruments must have was also important to make sure the instruments would high ratings in dust and water protection since the not rust and stay durable an entire year. Helix Bridge instruments are placed on the pile cap that sat on the

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NET is installed in the harsh conditions

Another major challenge for the NET system was the fact vibration created by the vehicles that travel on the bridge, monitoring perfectly. After year of monitoring, we can there were no continue power supply on the pile cap; this the heat, the sunlight sunlight and the rain. To reduce the attest that NET is a good and reliable product,” Lim said. was the first time for the NET system to constantly vibration, they place a 5mm rubber mat underneath the monitor a job site without continuous power. MSP instruments. To avoid the direct sunlight heat, they install “MSP owns more than 80 NET instruments now. On our Engineer came up with a solution to take the public additional sleeves outside the stand with 20mm gaps to customer concerns were whether MSP are able to deliver lighting power which operates only form 7p.m. to 7a.m. allow the heat to escape. To be honest, we feel easy on and complete in time, with the NET 1m red laser guide The engineer visited the monitor site every two weeks rain damage because the instruments are environmentally and Auto lock center, it gave us a lot faster without with a control box that included PDA, battery charger, rated to IP64. ” looking into the instrument during teaching the prisms.” power converter, timer, four car batteries with which the PDA can last for two weeks. After the installations, he said, “Our confidence in the Lim said: “With the combination of instruments and durability of the instruments increased because the data customized software, we have a decided edge over our There, software linked the PDA and server together for processing team examined the data closely for the next six competitors.” downloading data and updating the software from the months to ensure the accuracy was constant. instruments. “A year later, we continue to observe the raw data to Kenny Lim, Managing Director of MSP, said, “For the make sure it still maintains the highest accuracy. Even design of the instrument stand, we need to consider the during periods of heavy rain the instrument were still

Bay Front Bridge

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