This paper presents an experimental study on the evolution of the neutral axis’s depth failure with the ductility at bending on high-strength concrete beams. Nineteen simply supported beams were tested and analyzed. Each beam was loaded by two symmetrical concentrated loads applied approximately at the span’s thirds. The concrete strength and the longitudinal tensile reinforcement ratio vary from beam to beam. As far as the ductility is concerned, ductility indexes were defined in order to characterize such property. The ductility’s influence on the value of the neutral axis’ depth at failure is analyzed and discussed. From the experimental program, the neutral axis’ depth at failure in high-strength concrete beams seams to be a valuable parameter to preview the beam ductility. Therefore, the practical rule of limiting the neutral axis’ depth of the critical sections presented by some codes of practice for normal strength concrete can be extended to high-strength concrete.

This paper analyzes the load-carrying capacity of timber–concrete joints made with dowel-type fasteners. The scope of the work was to obtain information to be used in the design of timber–concrete composite structures. In order to achieve that, two different approaches were used: experiments with timber–concrete joints loaded in shear, and the use of nonlinear analytical models. Shear tests were performed using various timber species, concrete mixtures, and fasteners. The results from these tests are presented and compared with the results determined with three different analytical models. These models differ in the approach used to simulate concrete: linear–elastic, linear–elastic with crushing, and elastic–perfectly plastic. The analysis of the test results shows that the load-carrying capacity of this type of joint is significantly influenced not only by the strength of the materials but also by the shape of the fastener. From the three models proposed, the one assuming elastic–perfectly plastic behavi...