New-style Hamas tunnel, right, old-style Hamas tunnel, left (Photo: IDF spokesperson)
YNetNews By: YNet Reporters
Compared to the tunnels built during Operation Protective Edge, the newer ones benefit from greatly improved structural engineering and construction methods, which make them much less likely to collapse due to rainfall.
When comparing the tunnels discovered and destroyed during Operation Protective Edge in the summer of 2014 with the tunnel discovered two weeks ago, it is clear that Hamas has greatly improved the structural engineering of its tunnel and its construction methods.
The wall of the tunnels discovered during Operation Protective Edge consisted of pre-cast concrete slabs placed vertically, with reinforced concrete arches above them to prevent the tunnel from collapsing due to the weight of the soil above it.
In this type of construction, the wide vertical slabs are the weak point, and that is why Hamas is now building its tunnels using long, narrow concrete slabs laid horizontally, one on top of the other, within a metal frame.
This structure is much stronger and more durable. I can withstand not only the pressure from the soil overhead, but also explosions and fighting inside the tunnel. It also allows for safer working conditions on rainy days when water seeps into the work area.