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The problem of designing reinforced concrete plates and shells has interested researchers for a long time. The recent development of the computers' performance and storage capacity combined with powerful numerical methods revealed the need of a clear procedure to design elements subjected to membrane and flexure forces. In the present study this problem is formulated based on the equilibrium conditions and an iterative procedure is suggested. The computational code based on this approach is given, as well as some examples of the method.

A contribution to the definition of a novel safety format for the design of concrete structures based on non‐linear methods of analysis is the main purpose of this work. A brief discussion of design formats proposed by codes of practice is introduced. Probabilistic analyses of current concrete frames are performed and the corresponding results are used as a basis to derive simplified and coherent practical rules. The analyses have been carried out taking into account the non‐linear material behaviour and the variability of the structural parameters by simulation of probabilistic density functions. A simple procedure is proposed to evaluate the structural safety of concrete frame structures. Mean values are recommended to characterise the material properties to be used in the analysis and a global safety factor is defined to evaluate the structural design resistance.

The purpose of this paper is to present the implementation in a finite element (FE) code of a recently developed material model for the analysis of cracked reinforced concrete (RC) panels. The model aims for the efficient nonlinear analysis of large‐scale structural elements that can be considered as an assembly of membrane elements, such as bridge girders, shear walls, transfer beams or containment structures.

In the proposed constitutive model, the equilibrium equations of the cracked membrane element are established directly at the cracks while the compatibility conditions are expressed in terms of spatially averaged strains. This allows the well‐known mechanical phenomena governing the behaviour of cracked concrete elements – such as aggregate interlock (including crack dilatancy effects), tensile fracture and bond shear stress transfer – to be taken into account in a transparent manner using detailed phenomenological models. The spatially averaged stress and strain fields are obtained as a by‐product of the local behaviour at the cracks and of the bond stress transfer mechanisms, allowing the crack spacing and crack widths to be obtained directly from first principles. The model is implemented in an FE code following a total formulation.

The fact that the updated stresses at the cracks are calculated explicitly from the current spatially averaged total strains and from the updated values of the state variables that are used to monitor damage evolution contributes to the robustness and efficiency of the implementation. Some application examples are presented illustrating the model capabilities and good estimates of the failure modes, failure loads, deformation capacity, cracking patterns and crack widths were achieved.

While being computationally efficient, the model describes the complex stress and strain fields developing in the membrane element, and retrieves useful information for the structural engineer, such as concrete and reinforcement failures as well as the crack spacing and crack widths.

The article aims at analyzing the social representations of retirement in two different groups of professors – pre-retired and retired – from a public higher education institution. The goal is to explore the experiences, reflections, beliefs, and attitudes originated from the transition to retirement.

The research, of exploratory and descriptive nature, was guided by the Social Representation Theory (SRT) and took a qualitative approach. 16 professors were interviewed, 8 in each group (pre-retired and retired professors), using semi-structured interviews that followed a script designed to discover the main aspects of the transition to retirement.

Three figurative cores were raised – the financial aspect, the centrality of work, and the will to continue contributing, and the unpreparedness for retirement – and testimonies have shown heterogeneous representations. The study observed that although relevant, the bonus for continued services is not the main determinant for professors to continue working in the university.

The results of this study indicate the need to treat retirement as a complex and multidimensional process, offering a fresh perspective on the social representations of retirement in the academic context. The use of the Social Representation Theory to explore these perspectives adds to the originality of the approach, highlighting the multifaceted nature of the retirement process in this specific professional group.