The paper investigates the long-term fatigue and creep deterioration processes in historical brick masonry. Based on two independent laboratory test series, the relationship between stress level and life expectancy was considered for fatigue and creep loading in the form of SN type models. The process of deterioration was investigated with the help of acoustic emission technique to identify stages and characteristics of the damage accumulation process. Based on the test data and acoustic emission results, a joint SN type deterioration model was proposed to incorporate the static, fatigue and creep deterioration mechanisms. A mathematical relationship was proposed for the joint fatigue -creep model and good agreement was found between the test data and the proposed model.

Moisture is known to decrease the mechanical properties of brittle construction materials. The present study focuses on the influence of moisture on the mechanical behavior of ferruginous sandstone in order to understand and quantify this effect. The investigated Diestian and Brusselian ferruginous sandstone has frequently been applied in monumental constructions and many of these monuments presently suffer from material degradation and, in some cases, stability concerns. Experimental analysis is performed on different levels, from micro to macro behavior, in order to obtain a more detailed picture of the acting processes. Therefore, a methodology is proposed which combines established as well as advanced experimental techniques, involving non-destructive testing for pre-classification of the sandstone's quality, mineralogical analysis and investigation of mechanical properties under dry and saturated conditions. It was observed that the decrease of mechanical properties, such as strength and stiffness, is more pronounced for lower-quality ferruginous sandstone. It was also found that water adsorption by the sandstone during acoustic emission-controlled creep tests shifts the specimen's behavior from meta-stable creep damage to accelerated failure. These observations were linked to the results of the mineralogical study, in which the consolidation degree and clay content were analyzed and to the results of the microfocus computed tomography which visualized the fracture progress on a micro scale.

Many existing reinforced concrete (RC) structures are suffering from corrosion damage. The development of reliable tools to characterise and localise such damage is essential to assess the structural capacity. The acoustic emission (AE) technique has proven to be promising for this purpose. However, this technique poses challenges to reliably interpret the results and lacks rigourous validation.

Abstract. Current heritage analysis applications and documentation techniques for timber roof structures rely on manual measurements to provide the spatial data. Major simplifications are made to document these structures efficiently. However, these simplified geometric models provide less reliable results. Therefore, the need exists for more realistic models. Additionally, the exchangeability of information between varying parties is paramount. Hence, the construction elements should be defined in a Building Information Model (BIM). This allows users to reuse the model, allowing the distribution of information throughout the project. The goal of our research is to create a realistic BIM model of a complex heritage roof structure employing dense point clouds. The comparison of our complex geometric model to a traditional wire-frame model proves that our approach provides more reliable results in terms of geometry and structural behaviour. Our work covers the acquisition, the modelling and the structural analysis of timber roof structures.

The applicability of the acoustic emission (AE) technique to detect unstable damage accumulation in masonry, subjected to the creep failure mode, is investigated during short-term and long-term creep tests on masonry specimens. The damage accumulation is quantified using the results of the monitored AE event rates, which evolve as a bathtub shaped curve during the last phase of the creep tests. The bathtub curves are described using the Weibull function and a relation is found between the detected AE event rate and the time to failure of the specimens.