Vermeidung von Schäden an Schlitzwandfugen durch den Einsatz geeigneter Qualitätssicherungssysteme

Avoid of damage to diaphragm wall joints through the use of appropriate quality assurance systems

In recent decades diaphragm wall technology has proven to be the best way to carry out deep watertight pits in urban areas. The observation of execution failures of recent years has lead to the realization that the joint represents the weakest point of a diaphragm wall.
On the basis of execution failures possible damage and causes of damage are shown. An overview of common joint techniques results in a differentiated consideration of the possibilities of each joint system with its advantages and disadvantages.
Codes and standards give no clear guidelines for choosing the right joint system and quality assurance during installation although quality assurance systems exist for the joints which will be presented individually and will then be compared.
In the future, the firm, straight, and clean joint must be implemented before concreting the secondary element to minimize the risk of diaphragm wall pits. In future, not only the detection of possible defects during construction should be taken into consideration but a joint type should be developed, which eliminates causes of damage such as circulation concrete from the very beginning.