Pictures courtesy of Daily News

 

Repairs to the major sinkhole on Samsen Road in Bangkok are progressing as planned, with Transport Minister Phiphat Ratchakitprakarn expressing confidence that the road surface will be restored by 8 October. The incident, which began in the early hours of 24 September, created a 30 x 30 metre, 50-metre-deep hole near Vajira Hospital and the Samsen police station. Authorities say safety remains the top priority for both workers and nearby residents.

 

The collapse occurred, when part of the road gave way above a section of the underground mass transit tunnel. Since then, engineers have worked continuously to stabilise the area. Initial plans to pour 1,000 cubic metres of concrete at once were revised, with teams now pouring 360 cubic metres at a time, allowing the material to set properly. Over 1,105 cubic metres have already been poured, sealing the gap between the tunnel and station.

 

On 28 September, Mr Phiphat, visited the site with Associate Professor Dr Thanes Veerasiri, former president of the Council of Engineers and Kajphoj Udomthamphakdee, Governor of the Mass Rapid Transit Authority of Thailand (MRTA). The group confirmed that concrete sealing had been completed successfully. Dr Thanes added that monitoring showed only minor ground movement, which has largely stabilised since the incident.

 

More than ten isoscope cameras have been installed around the site to track building movement, with data monitored 24 hours a day. Mr Phiphat emphasised that work will continue with safety as the guiding principle. The MRTA has also established a coordination centre to assist residents and businesses with compensation claims and inquiries.

 

Next steps include removing debris, reinforcing the sides of the cavity with sprayed concrete and beginning sand–cement backfilling. The process is expected to take four to five days. Once the ground is raised sufficiently, broken foundation piles will be repaired to restore long-term stability.

 

Heavy equipment has already been deployed to clear obstructions and cut underground power and communication cables. The MRTA estimates that around 1,000 to 1,200 cubic metres of concrete will be used in total. Vajira Hospital remains operational, with outpatient services expected to serve up to 4,000 patients on 29 September. Traffic diversions have been signposted and parking restrictions enforced around Sangkhalok and Suan Oi roads to ease congestion.

 

If progress continues as planned, officials believe the surface will be safe for reopening by 8 October, though the date may shift by one or two days depending on weather conditions.

 

 

Key Takeaways

 

• Authorities aim to restore Samsen Road by 8 October after a major sinkhole incident.

• More than 1,100 cubic metres of concrete have been poured to stabilise the area.

• Safety monitoring and compensation measures are in place for residents and businesses.

 

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  Adapted by Asean Now from Dailynews 2025-09-28

 

 

 

 

 

Was it not initially mentioned that it would take a year?

 

i don't know how that could be repaired properly in less than 2 weeks?

1 minute ago, PJ71 said:

Was it not initially mentioned that it would take a year?

 

i don't know how that could be repaired properly in less than 2 weeks?

think you are right this is typical thai engineering  they need to stabilize the ground first, not just pouring concrete  the soils needs to be compacted in layers  and once the base as been compacted and Nuclear Density Gauge reading been taken then you pour concrete      this is the same as the roads  there is very little compaction carried out  and have never seen compaction tests taken 

Purpose of Soil Density Testing

The primary goal is to achieve adequate soil compaction, which increases soil strength, reduces settlement, and enhances the durability and load-bearing capacity of infrastructure like roads and building foundations. 

4 hours ago, Georgealbert said:

...created a 30 x 30 metre, 50-metre-deep hole  

 

The MRTA estimates that around 1,000 to 1,200 cubic metres of concrete will be used in total

 

1200 cubic meters of concrete into a 45,000 cubic meter sinkhole.  I sure hope they know what they're doing.  Offshore, I worked with a lot of extremely competent Thai engineers and tradesmen.  Ditto, working in our Bangkok office.  You gotta pay them well, but there are excellent Thai technical people available.  (Especially welders.  Ours did gorgeous work)

 

BTW, 45,000 m3 of sand weighs about 100,000 tons.  About the same as a modern American Super Carrier displaces, for a visual.

 

Perhaps that 1200 cubic meters of concrete is just to seal the thief zones where that 100K tons of earth apparently disappeared to?  It would be interesting to watch, but I won't be back on my monthly BKK visit until late October. 

 

Anyone looking for a great idea for a YouTube video should point a timelapse video camera at the site and keep it on throughout the job.  And/or a live feed...

 

37 minutes ago, MikeandDow said:

The primary goal is to achieve adequate soil compaction, which increases soil strength, reduces settlement, and enhances the durability and load-bearing capacity of infrastructure like roads and building foundations. 

You mean like when the dudes come by with the clipboards and say "Nope"?

 

The goal is to make sure you pass. They got clipboard dudes in Thailand?

4 hours ago, Georgealbert said:

monitoring showed only minor ground movement, which has largely stabilised since the incident

 

Mmeh.............it'll be fine.

How long will it hold??? From 1 year to 2 weeks is a lot  shortening to repair it decently I think... 

no investigation ?, they tunneled under the the  road......................incompetence no one held accountable, 

13 hours ago, MikeandDow said:

think you are right this is typical thai engineering  they need to stabilize the ground first, not just pouring concrete  the soils needs to be compacted in layers  and once the base as been compacted and Nuclear Density Gauge reading been taken then you pour concrete      this is the same as the roads  there is very little compaction carried out  and have never seen compaction tests taken 

Purpose of Soil Density Testing

The primary goal is to achieve adequate soil compaction, which increases soil strength, reduces settlement, and enhances the durability and load-bearing capacity of infrastructure like roads and building foundations. 

 

When you pour a couple of thousand cubes of concrete like they're doing here.....this is the best option. Below this is mud and the metro tunnel and station.....and that has likely been delayed for a year

The other major part is reinstating services....that'll be a nightmare!

14 hours ago, PJ71 said:

Was it not initially mentioned that it would take a year?

Yep, it was the very competent PM that stated such rubbish. 😂

Bangkok Sinkhole Repair Halted After 1,500 Tonnes of Concrete Leak into Tunnel

 

 

• Repair work on a major sinkhole on Bangkok's Samsen Road was halted after approximately 1,500 tonnes of poured concrete leaked into an underground tunnel.
• The leak occurred through a 30-square-metre breach in the subterranean tunnel's wall, which officials are now surveying.
• Engineers have suspended the operation and must wait for the initial concrete fill to dry and set before resuming the repair.

https://www.nationthailand.com/news/general/40055956

BTW the Chinese are once again involved in this construction.

UPDATE
Bangkok Governor Inspects Samsen Road Collapse Repairs

 

 

UPDATE
Samsen Road Remains Closed as BMA Ensures Ground Stability