Cleaning of Bismarck Monument in Hamburg, Germany
In the middle of the Elbe metropolis of Hamburg, between Landungsbrücken, St. Pauli and Michel stands the world's largest Bismarck statue. Kärcher cleaned the 34.3 metre high and over 100 year old monument over a period of almost two months.
In the middle of Hamburg, between Landungsbrücken, St. Pauli and Michel stands the world's largest Bismarck statue, which is currently being cleaned by Kärcher. The granite surface of the 34.3 metre high and over 100 year old monument is heavily soiled by biological growth such as algae, lichens and moss and by graffiti. The work will take a total of two months, during which Kärcher's experts will clean the enclosure wall, the pedestal and the statue itself of any contamination.
In order to determine the optimum process, Kärcher experts carried out various tests and created sample areas in advance. "The chosen procedure without chemicals removes the impurities in a gentle way," explains Nick Heyden, who as project manager of Alfred Kärcher SE & Co. KG, is responsible for the on-site implementation. "We are proud to be able to make a contribution to the preservation of the monument with our material-conserving cleaning technology".
卡彻的专家们使用了三种不同的清洁技术。首先，用手清除地表较大的植物，然后用热水高压清洁器清除灰尘、鸟粪和其他生物植被。80到90度的热水以1到2巴的压力撞击表面，这对花岗岩来说是一种特别温和的方法。然后，五位清洁专家使用低压粒子喷砂工艺和喷砂剂硅酸铝（粒度40-180μm）去除涂鸦和石灰沉积物。最后，用干湿两用吸尘器对整个纪念碑进行吸尘，最后再冲洗掉最后残留的污垢。
The cleaning was often done in the early morning hours.
The approximately 80 to 90 degree hot water hit the surface with a pressure of 1 to 2 bar - a particularly gentle method for granite stone.
Statue in tilted position
The cleaning of the monument built between 1901 and 1906 in honour of the first Reich Chancellor Otto von Bismarck is preceded by a comprehensive renovation, which is currently still in the planning stage. In order to use the 19-meter high base as an air-raid shelter, the foundation was filled with 2,200 tons of concrete during the Second World War - too much for the statics of the building. The monument was tilted and cracks appeared in the surface. One advantage of cleaning is that after removing the dirt, a precise inventory of the damage can be made.
All Facts at a glance
Country:Germany
城市：Hamburg
Soiling:Dust, bird droppings, biogenic growth, lime, graffiti
Cleaning technique:Hot-water high-pressure cleaner without chemical additives with 1-2 bar and 80-90 degrees water temperature, low-pressure micro particle blasting with fine aluminium silicate (40-180 μm) as abrasive
Execution:March-April 2020
