My opinion on the movement of Elena during the disaster, any correction or criticism for improvement please.
The mechanics behind the movement of the UBS along the 1st & 2nd explosions began with a massive steam explosion that acted as a piston, launching the 2,000-ton Upper Biological Shield (Elena) straight up from its seat. Originally buried about 4 to 5 meters below the reactor hall floor, the shield was thrown roughly 20 to 30 meters into the air, clearing its containment. As it rose, it violently pulled at the 2,000+ fuel and control rod channels welded to its bottom, dragging a mangled "skirt" of piping—later nicknamed "Elena’s Hair"—along with it. This "unzipping" of the reactor left the 7-meter-high graphite stack and 192 tons of fuel shattered and exposed in the open pit below.
While the lid was still airborne, the reactor pit became a giant combustion chamber. Oxygen rushed into the void, mixing with hydrogen gasand causing a runaway nuclear power surge (a second explosion) that was far more powerful than the first. This blast leveled the building’s walls, launched the 300-ton refueling cranethrough the side of the hall, and disintegrated the fueling floor's 350kg caps. Because the building's reinforced concrete walls were pulverized before the lid could land, the pit filled with debris in seconds. Consequently, when the shield finally crashed back down, it struck this new pile of rubble and came to rest at its famous 15° angle, wedged forever in the ruins.