This thesis is concerned with a study of the design of reinforced concrete slab structures. Such a study is most opportune at the present time when the basis of the design of reinforced concrete structures is being re-examined and design recommendations being reformulated within the concepts of limit state design. The work is divided into four parts. In Part 1 the methods of analysis available for the solution of reinforced concrete slab problems are first discussed. Particular attention is paid to the idealizations involved in the use of these methods and the degree to which they may be employed by the designer. Subsequent to an appraisal of existing design philosophies for reinforced concrete structures the recommendations for slab design contained in the present code of practice for structural concrete (CP 114 1957) are critically examined and a number of unsatisfactory features of these recommendations are pointed out. The actual behaviour of reinforced concrete slabs is discussed with particular reference to membrane effects which are generally ignored in existing methods of analysis and design recommendations. Having established the importance of membrane effects methods of analysis for reinforced concrete slabs acknowledging these effects are developed in Part 2. In particular in Section 4a finite difference method of elastic analysis for beam-slab structures which allows for full composite action between the slab and the supporting beams is presented. Using this technique the behaviour of various square uniformly loaded beam-slab panels is investigated. In sections 5 and 6 methods of analysis for predicting the ultimate load behaviour of simply supported rectangular reinforced concrete slabs are developed. These analyses allow for the menbrane effects which are observed in the large deflection behaviour of such structures. Correlation between these new solutions, existing methods of analysis and experimental results are examined. In Part 3 the results of three separate experimental investigations carried out by the author are reported. The behaviour of a series of Perspex beam-slab panels is compared with the predictions of the finite difference analysis refered to above and an alternative analytical approach using the finite element technique. A series of tests on reinforced concrete beam-slab panels is described in Section 8. The behaviour of the specimens is carefully studied with a view to determining the salient features which must be allowed for in the design of such structures. The correlation between the behaviour of the test panels and the methods of analysis described in Part 2 is examined. The results of a series of tests on rectangular simply supported uniformly loaded reinforced concrete slabs are presented in Section 9. Although working load conditions are considered, particular attention is paid to the collapse modes for such structures. In particular the formation at large deflections of in-plane bending hinges is noted. (The results of these tests are compared in Section 6 with the analysis developed by the author which allows for this effect). In Part 4a new basis for the design of reinforced concrete slab structures is presented. These proposals are based on an examination of the existing recommendations and experimental evidence presented by the author and other research workers. The need for methods of analysis which deal realistically with the behaviour of reinforced concrete slabs is apparent and the possible use of the analytical developments described in Part 2 is outlined.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:492537 |
| Date | January 1968 |
| Creators | Hayes, B. |
| Publisher | University of Manchester |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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