Baugrundrisiko in der Geotechnik

Abstract

Ground risk in geotechnics – Legal analysis in the context of geotechnical damage cases

This article examines geotechnical site risk from the perspective of construction contract law. Based on DIN 4020, it defines site risk as the danger that site properties critical to planning, tendering, and execution are not sufficiently identified, described, or accurately assessed in terms of their impact on the construction process. The general importance of homogeneous zones as an interface between geological description, geotechnical assessment, and cost estimation is emphasized. Typical disputes—ranging from unexpected abrasiveness to water ingress and soil adhesion—are outlined. Using a practical example, the article demonstrates that changes in soil properties triggered by construction methods—which are technically unavoidable and unforeseeable at the tendering stage or upon contract conclusion—can also be attributed to soil risk. In practice, this implies that a robust description and practical delineation of homogeneous zones helps prevent legal disputes.