This paper presents a comprehensive case study of the construction of a 10 km long large-span underwater tunnel under Taihu Lake using the cut-and-cover method. The main challenges for the design and construction of the tunnel are limiting soil deformation and tunnel settlement, controlling the groundwater table, improving the construction efficiency, and meeting the environmental requirements. The strategies to address these challenges were summarized, including a four-zone staged excavation configuration, the use of piles for tunnel settlement control, and the use of cofferdams and waterproof curtains for groundwater control. The effectiveness of these strategies was validated by field observations, including deformations and stresses of cofferdams, retaining wall deflections, vertical and horizontal ground movements, groundwater table variations, and tunnel settlements. The observation results indicated that the measured values were smaller than the design limits, and no damage or leakage was observed during construction. This case history provides a valuable reference for the design and construction of similar tunnels.

The Kahramanmaras, seismic sequence of February 6th, 2023, caused extreme damage and a significant number of casualties across a large region of Turkey and Syria. The paper reports on the survey activities carried out by the authors in the city of Golbas,& imath;, where extensive liquefaction took place. The damage to the built environment caused by liquefaction differs from that caused by typical inertial seismic actions, with quasi-rigid body displacement mechanisms, resulting in extreme settlements, tilts, and, in some cases, complete overturning. After a brief introduction to the geological features of the Golbas,& imath; area and a discussion of the seismic effects on the area, the paper reports and comments on the damage observed in one part of the city and provides some statistical interpretations.