It is impressive how some engineering activities are carried out without any planning, inspection, supervision or control.
Even though they may put lives and property at risk, they are often done without a project, without a risk analysis or any other prior measure that guarantees a minimum of security.
Just go there and do it. Until when?
Accident 1:
Reservoir falls on condominium during demolition!
Check out:
Facts:
1) The accident occurred on Sunday, August 23, 2020, in Diadema, SP
2) A company was contracted by CDHU to demolish the reinforced concrete reservoir, which previously supplied the condominium
3) The demolition was closely watched by the residents, who filmed, photographed, commented, in short, an even fun program on Sunday
4) At one point, part of the reservoir collapsed, rolling “downhill” without any control
5) It hit the power grid, walls and several cars, leaving some completely flattened. (See photos in comments)
6) Fortunately, no injuries
7) Work without a license
8) Cracks detected in buildings due to vibration
Prevention:
1) Structural demolition project
2) Risk analysis
3) Effective isolation of the area
4) Use of experienced demolition crew
Accident 2:
– Morning of 12/30/2020
– 2 reservoirs built in metallic structure
– Residential condominium in Cariacica, ES, delivered 14 days ago
– The structures collapsed with an interval of 40 minutes
– A worker was on top of one of them, being rescued by the CBM
Look:
Hypothetical analysis:
– These steel tanks have 1 or 2 upper cells and with this diameter, as a rule, they do not have a central column
– All the water weight of the upper cells are supported by the side (side plates)
– These sheets must also withstand wind and out of plumb forces, as well as geometric imperfections
– The structure undergoes flexion-compression, leaving the side subject to local buckling
– With buckling, collapse begins, with a progressive and irremediable increase in displacements
– When the column is dry, there is no circumferential traction, aggravating the buckling.
See photo of Reservoir 2
Prevention:
– Certified structural design
– Quality control
– Supervision of manufacturing and assembly
Accident 3:
– 2 Reservoirs collapsed with an interval of 40 minutes (accident 1)
– When removing the carcass from one of them, there was a third accident;
– The mooring straps broke;
– The carcass rolled and fell next to the crane;
– A piece of steel pipe was projected at great speed;
– Other wreckage was also projected;
– There was no isolation of the area, with people within the radius of action of the wreckage;
– The signalman was not wearing gloves or a helmet, and his glasses were on his forehead;
Understand:
Prevention:
– Cargo mooring project;
– Use of cradles (or saddles) to avoid load rotation;
– Effective isolation of the area;
– Correct use of PPE;
– Training.
TechCon Engenharia designs reservoirs, both in concrete and steel, as well as design, manufacture and assembly certifications.
Examples:
Tanks, Silos and Pressure Vessels
Metallic structures
Our offshore lifting projects: Click here
Our lifting courses: Click here
