Proposal for independent unit to monitor subsidence of Cho Mai road

The Cho Mai - Tan My road project was approved by the Provincial People's Committee in Decision No. 2495/QD-UBND dated October 19, 2016, the starting point intersects with National Highway 49 at Km10+217 (Pham Van Dong Street), the end point intersects with National Highway 49 and the road to Tam Giang Bridge at Km5+00. The total length of the route is nearly 5km, the cross-section of the route is completed according to the planning with a 36m roadbed.

The project has a total investment of nearly 195 billion VND, of which the construction value is about 123 billion VND, site clearance (GPMB) is 35 billion VND, started in August 2018 with an initial expected completion time of 3 years.

The investment objective of the road construction is to contribute to completing the road according to the planning, creating momentum to accelerate the implementation of the planning of Thuan An ward, meeting the transportation needs of the area, and creating a premise for attracting investors and building infrastructure.

The project consists of two construction packages: package 11 includes the entire construction and installation from Km0+00-Km2+204.07 undertaken by Dong Tam Construction Company Limited and package 14 is undertaken by the joint venture of Minh Dat General Construction Company Limited and Thien Phat Thinh Construction and Trading Investment Joint Stock Company. After many extensions, the project has only completed a number of items on the route, the project is still in disarray and has not yet taken shape.

According to the reporter's records, at package 11 at the beginning of the route, on the current 2km length of the road, the contractor has completed paving the road surface for about 1.5km, the remaining section has been filled with crushed stone. On the route, the sidewalk, drainage, and green space systems have not been completed. The project is still in disarray, but this package only has a few workers working with machinery and materials exposed to the sun and rain.

In particular, in this package, although the asphalt concrete paving has been completed, visually, the road surface has many ups and downs, showing signs of subsidence. This asphalt concrete pavement (although previously compensated by 15cm of crushed stone) - adjacent to the existing asphalt pavement - does not differ much in height, although only visually, it shows that in the past, the subsidence of the road surface here has been continuous and there are no signs of "cutting" the subsidence.

Similarly, in package 14, although the roadbed is being rolled and crushed stone is being mixed in some sections, according to the contractor here, the road surface has continued to sink in recent times, with no signs of stabilization, so the implementation of other items of the project has been affected.

Specifically, about 1.3km of package No. 14 is constructed by the joint venture of Minh Dat General Construction Company Limited and Thien Phat Thinh Construction and Trading Investment Joint Stock Company. Currently, the contractor has completed the pouring of graded soil, is rolling and grading crushed stone at some points, but the road surface continues to sink, forcing the contractor to continuously compensate for the soil.

Mr. NNH, Technical Officer of Package No. 14 of Minh Dat General Construction Company Limited, said that on the 1.3km route alone, the road subsidence is from 20-80cm but it has not stopped yet, the load has not been unloaded, the contractor has to compensate for about 6,000m3 of fill soil. Along with the increase in material prices, the lump-sum contract for the project... caused the contractor to lose billions of dong.

According to Mr. NNH, the contractor has constructed according to the design of the road, but now it continues to sink, so they have to continuously compensate for the land, "chasing" the design. Especially at the end of the route, near the construction project of Thien Phat Thinh Investment, Construction and Trading Joint Stock Company, according to the design documents, the loaded soil will be filled in for a while after the road "cuts" the subsidence, the load will be unloaded, the excess soil will be removed and transported away, but currently the road surface continues to sink another 30cm.

The reason, according to the construction unit, is that the road surface construction area is originally rice fields, so there are many mud pockets. After two rainy and flood seasons in 2020-2022, the weak geological foundation caused the road surface to continue to sink.

“With geological areas like this, in other localities, the construction of normal works will be done according to the design, put into operation, and accepted for settlement at that stage. After about 2 years to stabilize the subsidence, we will conduct monitoring and re-evaluation; at the same time, redesign the surface, continue to compensate for the crushed stone layer to resurface the road surface,” said Mr. NNH.

According to the representative of Minh Dat General Construction Company Limited, the construction units are currently in a "dilemma" because the embankment continues to sink and cannot be unloaded, causing other items to be affected. The construction unit believes that if the asphalt pavement is completed (like package 11 of the first section of the route), the road continues to sink, who will be responsible? And, the contractor will continue to have to compensate for the land filling, so the more construction is done, the more losses are incurred!

Mr. Ha Xuan Hau - Director of the Provincial Urban Development and Construction Investment Project Management Board informed that recently the investor had a meeting with the construction contractor to request additional and provide settlement monitoring data so that the design consultant could re-evaluate. In addition, the investor has submitted a report to the Provincial People's Committee proposing that an independent monitoring unit monitor the settlement, based on the data provided by the contractor, there will be a comparison to come up with a suitable treatment plan.

“This is a complicated issue, awaiting direction from the Provincial People’s Committee. The project has been behind schedule for a long time and the contractor has not yet finished grading the road surface in some sections, so we cannot say that asphalt paving will stop the subsidence,” Mr. Hau added.

In July 2023, the Provincial Urban Development and Investment Project Management Board issued decisions to administratively sanction violations of the construction contract progress of package No. 14 of the Cho Mai - Tan My road project against two contractors, Minh Dat General Construction Co., Ltd. and Thien Phat Thinh Construction and Trading Investment Joint Stock Company, with a total fine of more than 1 billion VND. The entire fine fee will be directly deducted from the acceptance and payment records for the completed volume of package No. 14 of the construction contractors.

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