How to cut a keva planks building - Blender bullet physics - keva collapse and destruction

keva planks tower demolition simulation done with blender 3D, blender game engine and bullet physics engine. The keva planks building is cut but the tower does not collapse. Tell me if you know an interactive simulation game where you can collapse towers. When I saw Phymec’s keva planks demolitions, I decided to make my own once, my favorites Phymec’s videos are : “Over 32000 planks ;-) Blender / Bullet Physics / SmallLuxGPU OpenCL“ “KEVA planks round tower buil