Surigao del Norte, Philippines – Department of Public Works and Highways (DPWH) – XIII released an update with regards to the construction of the new Anao-aon Bridge in San Francisco, Surigao del Norte. This new bridge is said to be the first-ever earthquake-resistant bridge in the country.
Since the 6.7 magnitude quake hit Surigao last February 10, 2017, commuters have been on grapple to traverse over a rickety one-lane bailey bridge. The strong quake caused the “two spans of 165 linear meter concrete Anao-aon bridge” to collapse. Consequently disconnecting the town of Surigao City—San Francisco and Malimono.
The bridge construction will utilize corrugated steel plates (CSP) as its primary material—tested and proven support that makes bridges resistant to earthquakes. The first phase construction, including the foundation construction and CSP materials procurement, has already started last April 12, 2018. As of August 31, 2019, it accomplished nearly 85.51%.
CSP is a lightweight construction material that is economical as it cuts off the construction time because it is easier to install. It is also durable to corrosion as the material is coated through Hot-Dip Process to extend its life service.
Moreover, the new bridge total cost so far reached a total of Php 79,919,988.36 million.
With CSP, the bridge lifespan lasts 70 years compared to concrete bridges that last around 40-50 years. For maintenance, the bridge can be easily replaced with new CSP materials and on affected portions only.
On top of that, the flexibility and lightweight characteristic of steel make it earthquake-resistant compared to concrete structures.
DPWH Caraga sent an augmentation request of around Php 75 million for next year’s infra program, overall completion of the bridge. They still need to install the remaining CSP, backfill, and concrete slabs as a carriageway.
In the Philippines, the most common bridge designs include beam, girder, and truss. However, in the new Anao-aon bridge, it features an arch design, giving it a fresh and artistic appeal.
According to DPWH-XIII Planning Engineer Glenn Castañeda in terms of weight distribution, the arch design has no weaker portions. It distributes the weight evenly, and wherein the “rounded structure pushes the weight outward toward each end.”
The man behind the world-renowned design is Engr. Glenn Castañeda while Alexandra P. Grado made the perspective drawing and visualization.
—(Source: DPWH Caraga)