ABSTRACT
An overview of the development of ground improvement by deep vibratory compaction starts in Germany between the two world wars. The worldwide economic crisis from 1929 to 1931 had a severe impact on the German construction industry. The absence of profits prevented badly needed investment. Mass unemployment reached over 30% and paralysed economic activity. Farsighted personalities, however, looked into new working and construction methods at a time when the government under Chancellor Brüning (1885-1970) tried to mitigate the worst misery by job-generating measures such as the first programme to build highways, which was then intensified under the Hitler regime after 1933. In this context, the need to compact large quantities of concrete, sand and gravel was the motive for numerous engineers to look for better and more efficient methods.
