The long-term behavior of adhesive-bonded timber-concrete composites is influenced by climaticchanges in temperature and relative humidity because of the different properties of wood, concrete and adhesive. Threedimensional material models, which take into account the hygrothermal and time-dependent behavior, were developed to predict the long-term behavior. The material behavior of the wood is highly influenced by the moisture content. Thus, the wood moisture content was calculated numerically as well as depending on the surrounding climatic conditions. The numerical models were validated with data from experimental investigations and applied to determine climatic conditions for further experimental investigations.