SUMMARY
     
     A key factor in the design of reinforced concrete structures is the accurate estimation of the anchorage length (or development length), because it can determine the geometric dimensions of the structural members. Therefore, bond between steel and concrete has to be studied in order to understand the mechanisms involved.
     
     In many circumstances, the anchorage of passive reinforcement takes place in zones where heavy transversal pressure exists. According to the experimental data analyzed, these transversal pressures highly improve bond conditions in passive reinforcement. This is a very usual situation in beam-end anchorages (under the load application point), corbels and anchorage in pile caps. These are examples of CCT nodes (compression-compression-tension), where the transversal pressure is related to the inclined angle of the strut developed in those D regions.
     
     In spite of its importance, this advantage hasn’t been taken into account in the numerical expressions which permit the evaluation of the anchorage length included in EHE. Moreover, only in a limited amount of research has included the transversal pressure as a parameter design and most of them are headed towards the determination of bond stress-slip relationships (?-?) between reinforcement and concrete.
     
     Therefore, an investigation project was requested and granted by the Spanish Ministry of Science and Technology, named “A theoretical-experimental study of passive reinforcement anchorage in reinforced concrete D regions, including the effect of transversal pressure”. The aim of this project is the analysis of the anchorage conditions of passive reinforcement in D regions under transverse pressure, by means of experimental and numerical research.
     
     The main objective of this doctoral thesis is the theoretical and numerical analysis of the tests developed in the experimental campaign included in the project, in order to attain this objective, a numerical model including bond between steel and concrete has been developed and included into a finite element code for the analysis of reinforced concrete structures. By means of the experimental results, this model has been checked and calibrated. Then, an exhaustive analysis of the results has been carried out and a proposal of response prediction model is presented. Finally, the validation of the numerical model presented in this doctoral thesis is shown, by means of some tests found in the bibliography.