A navigable lock is temporarily 'empty' due to maintenance. After some time there is a significant increase in the air temperature, which causes thermal expansion of the inner side of the lock, while the soil-side of the concrete block remains relatively cold. This leads to backward bending of the wall and, consequently, to increased lateral stress in the soil behind the wall and increased bending moments in the wall itself.

Figure 1. Temperature distribution around the concrete lock (in magenta/red)

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