Ths structure is a simple "goal post design" (refering to the game of football (soccer)). That is two vertical uprights bridged between by a single cross-bar. This frame straddled the entrance ramp to a supermarket car-park.
And someone had driven a vehicle into it...
A note I made about this job just afterwards:
The significance or particular interest of this job was in realising the engineering decisions in this apparently incredibly simple structure. Put simply, it's two identical uprights and a crossbar. The uprights sit on two identical(? - nearly) baseplates bolted with anchor-bolts to the pavement. The thing is - which impinged on my welding decisions - is how the structure responds to applied load - impact of a vehicle with the height restriction bar. The thing cannot be infinitely strong. So it preferentially undergoes progressive collapse. And we see that this has happened to the top left mounting bracket of the crossbar. The angle has torn and twisted. Likewise, strongest and easiest to fix the upright to the baseplate would be a large fillet weld. But if overloaded, if - rip the masonry anchor bolts out of the concrete - tear the fillet weld this is a final failure with no remaining strength or restraint. If doing these repairs, for each size of upright box-section on adequate thickness baseplate, there is an optimum size of angle-iron forming the fillet between base-plate and upright which will give optimum strength and rigidity but which will undergo progressive tearing of the weld fillet between angle-piece and baseplate.
