Bangkok: The Society of Structural Engineers is currently investigating a water leak in a subway tunnel that has raised concerns among local residents. Despite no new cracks appearing in surrounding buildings, residents are urging authorities to expand inspections beyond the immediate 30-meter radius. The Association of Structural Engineers has highlighted the importance of hourly monitoring of subsidence and cracks. While buildings are deemed safe for now, they emphasize the need for vigilance and contingency planning for all possible scenarios.
According to Thai News Agency, the water leak occurred in a drainage pit under the subway tunnel during the construction of the Southern Purple Line elevated train. Traffic closures have been implemented, advising drivers to avoid Prachathipok Road between Ban Khaek Intersection and Wongwian Yai to facilitate tunnel repairs and improve the road surface. This closure has led to significant traffic congestion, particularly around Wongwian Yai, as vehicles divert to other routes such as Lad Ya Road, Somdej Phra Chao Taksin Road, and Inthraphitak Road.
The disruption has forced many commuters to navigate around high-risk buildings, with officials cordoning off dangerous areas. Today, further inspections were conducted to assess whether additional evacuations might be necessary for enhanced safety. Professor Dr. Amorn Pimanamas, President of the Structural Engineers Association of Thailand, has been on-site to evaluate the impact of the leak, which is suspected to have caused subsidence and cracking in nearby buildings.
Initial findings suggest that the construction pit, the lowest point of the tunnel, was not adequately protected, raising questions about the soil improvement measures taken during construction. The main concern now is not only the water leakage but also the potential for soil erosion into the tunnel, which could lead to road surface subsidence and compromise the foundations of nearby older buildings.
The Structural Engineers Association of Thailand has begun measuring the building's settlement levels to establish a reference standard. These measurements will be repeated to track the settlement rate and its connection to building cracks, aiding in evaluating the effectiveness of current remediation efforts. Additionally, efforts to reduce groundwater pressure through deep well drilling and sealant injection at crack points are underway.
The subsidence mirrors a depression-like area around a 30-meter deep construction pit. While the overpass area near the center of the depression is considered high-risk, experts caution against panic. This situation differs from a previous incident at Vajira Hospital, where numerous voids facilitated soil flow. Nonetheless, residents are advised to report any new or expanding cracks to authorities promptly to ensure ongoing safety.