Since several decades, the deep soil mix (DSM) technique has been used for ground improvement works. But in recent years, this technique has been increasingly used for structural applications. Standardized guidelines for the execution and the design of this kind of applications are not currently available. For the purpose of developing such guidelines, mechanical characteristics of DSM material were investigated. Within the framework of a Flemish regional research program (IWT 080736), DSM material from 38 Belgian construction sites, with various soil conditions and for different execution processes, has been tested. Internationally QA/QC activities are commonly related to tests on core samples for the determination of the Unconfined Compressive Strength (UCS) and the modulus of elasticity (E) of the material. Both values allow an approach of the design which takes into account the bending characteristics (EI), the deformation (E), the arching effect (UCS) and the structural resistance (UCS) of the element. For the semi-probabilistic design approach presented in Eurocode 7, a “characteristic value” of the UCS has to be defined as part of the design of DSM structures. The present paper discusses the definition of this value.