## 3 Experimental Layout  
A comprehensive experimental campaign was carried out comprising concrete characterization tests, adhesive mortar material tests, and structural tests performed on bonded anchors for two different chemical products. In total 50 concrete tests, 34 pull-out tests, and 50 anchor time-to-failure tests were carried out.  
It is well known that concrete is an aging material and that the material properties are improving with time due to ongoing hydration reactions, especially in the first few weeks. The evolution of the concrete material properties are highly dependent on the temperature and humidity state inside the concrete member which, in turn, is influenced by the storage conditions. The installation of bonded anchors at significantly different times associated with different mechanical properties of concrete but also temperature and humidity states could affect the development of bond properties and it certainly influences the short-term concrete capacity [27] and concrete creep contribution [21; 28] in sustained load experiments.  
Due to the aforementioned reasons and limited availability of sustained load frames, it was not possible to start all sustained load tests at the same time. Furthermore, it was desirable to minimize any aging effects while sustained load tests are ongoing. Therefore, the bonded anchors were installed in 7-month old concrete specimens.  
All anchor tests were performed on cylindrical concrete specimens of sufficient size to prevent splitting (details are provided in later chapters) which had been continuously stored inside the laboratory ensuring a well-defined temperature and humidity state inside the concrete specimens. All anchor tests including preparation and installation were carried out in controlled environmental conditions with a constant temperature (\(T\)) of \(22\ \pm\ 0.5\ ^{\circ}\)C and relative humidity (\(RH\)) of 50% with variations of \(\pm 3\)%.  
Structural tests on bonded anchors comprised both short-term pull-out tests in a confined configuration at different loading rates and long-term experiments. The anchors were loaded hydraulically at a precisely controlled loading rate up to different relative load levels (with respect to the short-term pull-out capacity). After that, the load was actively controlled to remain constant with a hysteresis of less than approximately 1 kN. The displacement was continuously recorded at a sampling rate of 50 Hz for high load levels and tests expected to fail within hours, while for the lower load levels and longer tests the sampling rate was decreased to as much as 1 Hz.  
Two adhesive materials were investigated, further called Product 1 (epoxy based) and Product 2 (vinyl-ester based). Only one anchor type, threaded bar M16, (\(d_{nom}=16\) mm, bore hole diameter of 18 mm) and one embedment depth, \(h_{ef}\), of 75 mm are considered in this experimental work. The selected embedment depth corresponds to 4.7 times the anchor diameter and also the maximum aggregate size. All anchors were made from threaded steel bars with a steel grade of 12.9 corresponding to a yield strength of 1080 MPa and a tensile strength of 1200 MPa that are guaranteed by the producer.