Building a highway viaduct in the Mekong Delta is a superior solution?

Is building a viaduct the best and cheapest solution to overcome the shortage of river sand and highway embankment soil in the Mekong Delta?

Ho Chi Minh City - Trung Luong Expressway, the section passing through Long An province, has been built as a viaduct - Photo: MAU TRUONG

As reported by Tuoi Tre Online , a business has just proposed to the Prime Minister to build a highway overpass in the Mekong Delta, with an investment rate of about 12 million VND/m² of highway.

This proposal received much support from Tuoi Tre Online readers.

Save sand, no impact on flow

According to reader Nguyen Hung Pham: "This is the best and cheapest way to build a highway, saving 50% of land resources if we build a double-decker road. The road is completely unaffected by rain and floods."

Account pnth****@gmail.com said: "Building viaducts for highways in the West, although the initial cost is higher, in the long run, viaducts have many advantages.

It is highly durable, saves a significant amount of sand, and does not greatly affect the flow, subsidence, or riverbank erosion. In particular, the viaduct also drains floods very well."

"The West is a low-lying area that is prone to flooding during the rainy season, so building a highway on an overpass is the best solution" - reader nguy****@gmail.com agreed.

Account ngoc****@gmail.com commented: "This solution is suitable and feasible when we are lacking the necessary sand source. Especially for areas with weak ground like the Mekong Delta."

Reader levi****@gmail.com shared: "In Thailand, places with weak ground like the Mekong Delta have been building viaducts for highways for decades."

Visiting Thailand, reader anph****@gmail.com saw that this place is building an elevated highway hundreds of kilometers long. The design is like a viaduct with a solid pile foundation, so it will be very safe and long-lasting.

Readers from the Western Region gave four reasons for building a highway overpass: "First, to quickly put the highway into use. Second, not to block the water flow, not to prevent alluvium from depositing on the fields. Third, to drain floods. Fourth, not to take sand to cause landslides in the riverbed and riverbanks.

It is said that it increases costs, but in fact, building an overpass reduces costs because the price of sand has increased a lot due to lack of supply. Building an overpass also solves the output problem for domestic cement and steel companies."

Need to build a viaduct over weak ground immediately

Dr. Pham Viet Thuan, Institute of Natural Resources and Environment Economics of Ho Chi Minh City, said that in the current context of the country's shortage of foundation materials, the solution of building overpasses on roads through weak soil areas needs to be implemented immediately.

In fact, this solution has been deployed on some highway sections of our country.

In the world, many countries such as China, Thailand, Singapore... have implemented this plan for a long time.

Regarding the opinion that the investment cost for building viaducts is often higher than the traditional embankment method, Dr. Thuan emphasized the need to evaluate the effectiveness comprehensively, including the outstanding advantages of viaducts.

Not only does this solution reduce the need for sand mining, it also brings many economic and technical benefits, minimizes environmental impacts, and limits the division of residential areas.

In particular, viaducts demonstrate superiority in areas with complex terrain such as riverbanks or mountain slopes.

In addition, the construction process of the viaduct is also easy when using Super T beams, which significantly shortens construction time.

Meanwhile, building a road base through weak soil often requires sand to handle the load for 10-12 months, and maintenance costs after completing the road are also higher.

Dr. Thuan also noted that with the current Super T girder casting technology, meeting the construction progress of expressways has become much simpler than in previous years.

Many domestic enterprises have boldly invested in modern beam launching equipment, creating favorable conditions for project construction.

In fact, the recent sand shortage is affecting the progress of highway construction, especially in the southern region, where a series of large projects are being implemented.

"Therefore, for new projects, the viaduct option will be an effective solution when passing through weak soil areas or low-altitude areas that require a large amount of filling materials. The remaining sections on the route can apply a conventional foundation.

To ensure success in implementing this plan, it requires determination from advisory agencies, as well as careful survey and assessment of the entire route's terrain to choose the appropriate plan," said Dr. Thuan.

Source: https://tuoitre.vn/xay-cau-can-cao-toc-tai-dong-bang-song-cuu-long-la-phuong-an-vuot-troi-20241219164540577.htm