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[en] Research providing guidance on management of aging reinforced concrete structures is summarized. Topics covered include a materials property database, an aging assessment methodology to identify critical structures and degradation factors that can potentially impact performance, guidelines and evaluation criteria for use in condition assessments, and a reliability-based methodology for current condition assessments and estimations of future performance. Applicability of nondestructive evaluation and repair-related technologies is addressed
[en] The increase in construction activity in the Philippines, reinforced concrete building is still a favorite among designers, because it is much cheaper to build and it requires qualified welders, etc. and extensive nondestructive testing and inspection of metals, welds and castings. Of all the techniques radiography is widely used for concrete
[en] The displacement-based seismic design approaches are evaluated utilizing shaking-table test data of a 1:3 scaled reinforced concrete shear wall structure, provided by the International Atomic Energy Agency. The maximum inelastic responses such as the top displacement and base shear forces are estimated using the two prominent displacement-based approaches, i.e., the capacity spectrum method and the displacement coefficient method, and compared with the measured responses. For comparison purpose, conventional response spectrum analysis and nonlinear time history analysis are also performed. The results indicate that the capacity spectrum method underestimates the response of the structure in inelastic range while the displacement coefficient method yields reasonable values in most cases
[en] The present paper aims to contribute to the knowledge concerning the seismic assessment of load bearing masonry buildings with reinforced concrete slabs. The final goal of the present research was to propose a simple, yet accurate, methodology to assess the seismic safety of existing masonry buildings. The methodology here presented was based on the so-called ICIST/ACSS methodology with major improvements such as the extension to load bearing masonry wall buildings and the consideration of the effects of one of the most common strengthening solutions for masonry walls, here referred to as reinforced plastering mortar, as well as the possibility of considering four levels of increasing refinement: global, by alignment, by wall panel and by wall element. An extended research was performed on the existing methodologies to evaluate the seismic structural risk of load bearing masonry buildings, briefly describing methodologies similar to the one proposed, namely all of those that have in common the fact that they are based in the physical comparison between the resisting and acting shear forces at all storeys and along the two orthogonal horizontal directions. A case study is presented to check the applicability of the proposed methodology. The case study showed that the proposed methodology is relatively simple to apply and has a sufficiently good accuracy when compared with alternative methodologies. The degree of refinement of the analysis (global, by alignment, by wall panel and by wall element) must be taken into consideration and successively more complex analyses may be required when the results of simpler analyses are inconclusive.
[en] Up to now the design of reinforced concrete linear members is performed with the help of an inconsistent design theory, which nevertherless is sufficiently safe and simple to be used in the practice. The purpose of this paper is to present a rational reinforced concrete design method which is not too dissimilar to the present design rules, but is capable of defining consistently internal stresses along a reinforced concrete section. The present status of the completed computer procedures allows the analysis of linear reinforced concrete members formed by laminar reinforced concrete plates presenting variable thickness. A practical approach is presented for which the concrete and steel section is constant along the member axis. In this case, the concept of the equivalent section is introduced, which allows a simple analysis of the stress pattern along the member section. (Author)
[pt]Ate agora o projeto de membros lineares de concreto reforcado e feito com a ajuda de uma inconsistente teoria de projeto, que nunca e suficientemente segura e simples para ser usada na pratica. Apresenta-se um metodo de projeto racional de concreto reforcado, que nao e tao bem definido em relacao aos projetos reais, mas e capaz de definir tensoes internas consistentemente ao longo da secao reforcada de concreto. O estado atual do procedimento do programa de computador permite a analise dos membros lineares de concreto reforcado formado por placas laminares de concreto reforcado apresentando espessuras variaveis. Apresenta-se uma aproximacao pratica para a qual a secao do concreto e aco e constante ao longo dos eixos dos membros. Nesse caso, o concreto de secao equivalente e introduzido, o que permite uma analise simples da tensao padrao ao longo da secao membro. (E.G.)
[en] Reinforced concrete members subjected to cyclic inelastic deformation may exhibit both stiffness and strength degradation depending on the maximum amplitude and the number of cycles experienced by a member. Many of the currently available models do not accurately simulate the cycle-dependent stiffness loss often observed during the experiments. An analytical model based on a damage parameter which is a function of the cummulative cyclic inelastic deformation is proposed. The model is able to capture the complete hysteretic response and is simple to implement. The results, based on this model are compared with other models in terms of their displacement history and energy dissipation subjected to the same simulated earthquake excitation. (orig.)
[en] In comparison with the RC(Reinforced Concrete) structure, SSC(Stiffened Steel plate Concrete) module has the advantage of short construction period, good quality control and less cost. In this study, to verify shear behavior of SSC wall module under out of plane loading, several tests were conducted according to the rib reinforcement ratio, stud reinforcement ratio and shear reinforcement ratio. On the basis of test results, it is found that rib reinforcement ratio is the main factor of securing the loading capacity of SSC structures
[en] The present paper reports on damaged prestressed reinforced concrete (PRC) beams and reinforced concrete (RC) beams experimentally investigated through dynamic testing in order to verify damage degree due to reinforcement corrosion or cracking correlated to loading. The experimental program foresaw that PRC beams were subjected to artificial reinforcement corrosion and static loading while RC beams were damaged by increasing applied loads to produce bending cracking. Dynamic investigation was developed both on undamaged and damaged PRC and RC beams measuring natural frequencies and evaluating vibration mode shapes. Dynamic testing allowed the recording of frequency response variations at different vibration modes. The experimental results are compared with theoretical results and discussed.
[en] Highlights: • Analysis of RC panels with different transverse reinforcement are presented. • The conventional RC panel with T-bar is used for the purpose of comparison. • Effects of transverse reinforcement arrangement and its ratio are presented. • Efficient design of RC panel is recommended. - Abstract: The effects of transverse reinforcing rebar on the penetration resistant capacity of the reinforced concrete (RC) panel still remains a challenging problem in the field of civil and structural engineering. In the present paper, we numerically analyze the penetration resistant capacity of three proposed panels with different transverse reinforcing rebar arrangements. The obtained results are then compared with reference solutions derived from the conventional RC panel using T-bars. The components of the RC panel, missile, and support system are fully developed. Material nonlinearity, which considers erosion damage, is employed in this simulation. The IRIS Punching tests are used for validating the numerical modeling of the RC panel subjected to impact loading. Parametric studies with varying transverse reinforcing rebar arrangements and ratios are performed to investigate the penetration response of RC panels. The present numerical result shows that the proposed panels offer a better penetration resistant capacity than that of conventional panels using T-bars. We thus recommend an efficient design of RC panels with a proposed transverse reinforcing rebar arrangement.