The design and the verification of anchorage to concrete are currently covered by the so called "Concrete Capacity Design" approach, which is adopted in the most recent codes and national regulations. Although it is quite advanced, such an approach is built on a wide range dataset, which encompasses both cast-in and post-installed anchors with very different geometry and tested under different boundary conditions. As a result, the CCD method was developed in a consistent way adopting the simplifying assumption that some parameters, such as the head-size, have a negligible influence on the pull-out capacity of the anchoring system. As the head-size increases, some authors found that the method could be rather conservative, while others found that the method is still accurate. Within this context, a literature review of the research studies and of the available formulas for predicting the capacity of cast-in anchors is addressed in this paper, focusing on the effect of the head-size.

The work mainly discusses the use of the Ground-Based Synthetic Aperture Radar (GBSAR)\ud \ud interferometry technique to observe and control the behavior of earthfill or rockfill\ud \ud embankments for dam impoundments. This non-invasive technique provides overall\ud \ud displacements patterns measured with a sub-millimeter accuracy. The need of reliable\ud \ud monitoring of old embankment dams is rapidly increasing since a large number of these\ud \ud structures are still equipped with old monitoring devices, usually installed some decades ago,\ud \ud which can give only information on localized areas of the embankment. A case study\ud \ud regarding the monitoring of an earthfill dam embankment in Southern Italy by means of\ud \ud GBSAR interferometry is presented

The effect of bearing pressure on the behavior of cast-in anchors is addressed presenting the results of an experimental campaign on cast-in anchors with different head type and same embedment depth. In particular, three cast-in anchor solutions were tested with the anchor-head ranging from relatively small head (high bearing pressure) to very large head-size (low bearing pressure). For the small head-size only, the anchor is installed using high strength grouting mortar after the hardening of the base concrete material. The concrete base member was lightly reinforced. Anchors were tested under axial force and different mechanical response (load-displacement) are observed. Failure modes change depending on the anchor's type. The force transfer mechanism might migrate from pure concrete cone formation to structural collapse of the concrete base member. In some cases, the cone surfaces can be clearly recognized despite of the presence of a splitting crack. In other tests a plate failure was obtained, characterized by the presence large triangular segments between cracks radially arranged. This aspect is strictly related to the bearing pressure at the anchor-head location. Indeed, a hydrostatic stress-strain field is developed with different gradients according to the head-size. Small head-size leads to an increasing of the bearing pressure with severe crushing of concrete and consequent reduction of the expected load capacity. Furthermore, the observed failure mechanism suggests that the crack pattern propagation is unaffected by the presence of grouting mortar.

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In the present paper, the safety reduction in anchor groups composed of cast-in place headed anchors was experimentally investigated. In particular, groups of two anchors were installed in concrete members designed such that one of the anchors was located in a crack and the other one in plain concrete. The samples were loaded in tension, thus simulating a connection with clamped rotation under both monotonic and cyclic conditions. The results are commented and discussed demonstrating how the presence of uneven crack distribution could lead to a safety reduction, which should be properly taken into account in the design of anchor groups.