Project: Jena CHP

MB Spezialabbruch - Projects: Jena CHP - dismantling of reinforced concrete chimney using DriveBreaker

Client: TEAG Thüringer Energie AG
Jena CHP, Winzerla
Reinforced concrete chimney, height: 225 m
Project time frame:

The dismantling of the 225-meter-high reinforced concrete chimney of the combined heat and power plant in Jena takes place in three phases.

First, basic preparatory work on and in the chimney will be carried out as part of the first phase, including the installation of suitable and certified height-access technology such as a climbing mast platform, and the erection of a suitable assembly platform on the chimney flue cross-section at height. As part of a comprehensive contaminant cleanup, the inner lining and insulation material will be removed and then properly disposed of. A complicating factor over the course of this work is the dust generated by the impact of the removed materials on the ground inside the chimney. To prevent the dust from escaping from the opening at the bottom of the chimney into the surrounding area, MB Spezialabbruch uses special equipment designed for this purpose, the Hydroshield.

The subsequent dismantling phase serves for the demolition of the chimney outer shell.

For this purpose, a special demolition device, known as the DriveBreaker, is brought to the initial height of the chimney in individual parts. To make this possible, corresponding preliminary work is being carried out. The electrically operated DriveBreaker will reduce the chimney to a height of 105 meters. The demolition equipment is remote-controlled by trained operators located on a bracket scaffold. Using the attachment connected to the boom, the chimney rim is successively removed. During the demolition process, the DriveBreaker moves on the rollers of its substructure as well as by controlling the height of the boom legs, decending into the excavated lower level and thus constantly following the demolition site. The demolition material loosened in the process falls into the interior of the chimney and is removed at regular intervals.

Jena CHP - DriveBreaker, Copyright: Ostthüringer Zeitung/Kai Mudra
DriveBreaker in action (Photo: Kai Mudra, Ostthüringer Zeitung)

Since the concrete thickness of the chimney increases as the height of the structure decreases, a second, more powerful special demolition rig is used at a height of 105 meters. This Spider Excavator is equipped with a demolition hammer and ensures that the concrete removed from the chimney outer shell point falls inside. The mode of operation of this demolition device is essentially the same as that of the DriveBreaker. The difference is primarily in the size and weight of the Spider Excavator, which allows for a greater range. This demolition equipment has six separately controllable height-adjustable legs, which can compensate for the different levels of the demolition edge during the process. During the work process, the operators are on the climbing mast platform, which, following the progress of the demolition, is also gradually dismantled and thus adjusted to the demolition level. Using this technique, the chimney is reduced to a height of about 20 meters. The Spider Excavator is then lifted off the remaining structure with a mobile crane.

MB Spezialabbruch - Projects: Jena CHP - dismantling of reinforced concrete chimney using Spider Excavator
Spider Excavator in action (Photo: MB Spezialabbruch GmbH & Co. KG)

The final dismantling of the remaining approximately 20-meter-high reinforced concrete chimney of the Jena CHP is then carried out using conventional excavator demolition technology.

The concrete produced during demolition is processed on site and recycled.

The following video will provide you with an idea of how the demolition takes place