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Item type:Publication, Access status: without files , Assessment of a cantilever slab under multiple concentrated loads failing in shear using analytical and numerical methods(fib. The International Federation for Structural Concrete, 2026-06); ; The shear capacity of bridge deck slabs has garnered attention in the assessment of existing bridges from several countries, as current codes prescribe heavier design loads and more conservative expressions of shear capacity. In this context, several studies in the literature investigated the shear capacity of one-way slabs under concentrated loads. Nevertheless, most of them applied a single concentrated load to the slabs, which may not be representative of the combined concentrated loads on bridges. This paper investigates the shear capacity of a cantilever slab tested in the literature under the combination of four concentrated loads. To this end, analytical and numerical analyses were conducted to predict the shear capacity of the slab, and the results were compared with the tested resistance. The results indicate that analytical and simplified finite element analyses may provide accurate predictions of the shear capacity using recommendations from the literature. Additionally, the non-linear finite element analyses provide important insights into the behaviour of the tested slab.Publicationtype: Conference Paper17 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Experimental investigations on shear failure in RC slabs subjected to distributed and concentrated loads - Technical Report(Technische Universität Hamburg, Institut für Massivbau, 2024-10); ; ; Versuchsbericht über eine Versuchreihe zum Thema Querkrafttragfähigkeit von Stahlbetonplatten ohne Querkraftbewehrung unter kozentrierten Lasten und zusätzlichen gleichförmigen Lasten.Publicationtype: Technical Report49 70 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , New approach for shear design of reinforced concrete slabs under concentrated loads based on tests and statistical analysis(2020-09-15); ; Despite the international research activity, the shear strength of reinforced concrete slabs without shear reinforcement is not yet satisfactorily resolved. In particular, deck slabs of existing bridges often show significant deficits in design shear capacity, although no damage has been reported so far. A test series of 14 large-scale cantilever slabs subjected to concentrated loads was conducted and analysed at the Hamburg University of Technology. Varying the distance between the concentrated load and the support in a previously unexamined wide range led to new considerations regarding the shear capacity in RC slabs. The ultimate and residual loads of the test specimens, as in many other studies on this topic, clearly exceeded the values for vehicle load assumptions in the current standards. In contrast to previous studies, a large shear slenderness in the load arrangement could be realized in the tests. This was the basic requirement for one of the key findings: The critical shear crack occurs locally in the area of load application and not at the support. Thus, shifting the design section for shear close to the concentrated load is reasonable, while in many approaches a critical section close to the support is chosen. Furthermore, the often-used effective width beff, which depends on the distance of single loads to the support, does not seem justified. The shear forces should be determined by finite element analysis, a common method in practice, which can consider the spatial load transfer and the stiffness of the support in a realistic manner. The new design method presented here is therefore not primarily concerned with the shear resistance, as other investigations are, but first on the side of determining the relevant internal shear forces, which are initially higher in the design section proposed here. Only in a second step is a preliminary factor C*Rd,c for the calculated resistance determined by means of a well-founded statistical evaluation. For this purpose, a database with 45 tests on RC slabs has been established. The new design approach provides significant greater shear capacities than the current regulations.Publicationtype: Journal Article181 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Shear design of concrete bridge decks without shear reinforcement(2019-08-22); ; Many older concrete bridge decks in Europe, mostly built without transverse reinforcement, show a significant lack of shear capacity due to increasing traffic loads and changes in design. Strengthening the slabs for shear is difficult and very expensive. Thus, more reliable design methods are urgently needed to overcome the calculated safety deficit and in order to avoid unnecessary retrofitting. In this paper a new design method will be presented which gives at least 40 % higher shear capacities than current design rules (EN 1992-1-1:2004; Eurocode 2 Part 1 (2004), in the following EC2-1). This approach is based on the examination of full-scale tests of cantilever slabs and statistical evaluation of a database with test results of reinforced concrete slabs under concentrated loads. Next, this paper shows the advantages and limitations of probabilistic analysis.Publicationtype: Conference Paper232 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Solution approaches for the new construction of the world's highest water-saving lock(2019-08-01); ; 8 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Increasing the design shear strength of concrete bridge decks by tests and statistical analysis of a shear database(2019-06); ; Publicationtype: Conference Paper168 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Querkrafttragfähigkeit von Stahlbetonplatten ohne Querkraftbewehrung unter konzentrierten Einzellasten: Teil 2: Vorschlag für ein neues Bemessungskonzept(2019-04); ; Shear capacity of reinforced concrete slabs without transverse reinforcement under concentrated loads. Part 2: Proposal for a new design model. Despite intense national and international research activities, the shear capacity of reinforced concrete slabs without shear reinforcement has not yet been satisfactorily clarified. Numerous older deck slabs of concrete bridges show a lack of shear resistance in the transverse direction. Retrofitting is hardly possible. In this paper, a design model is presented on the basis of tests and statistical investigations, which results in approx. 50 % greater shear capacities than according to current regulations.Publicationtype: Journal Article254 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Querkrafttragverhalten von Stahlbeton-FahrbahnplattenThe present work deals with the load-bearing behavior of reinforced concrete slabs. The focus is on the load transfer of concentrated single or block loads, as they occur in bridge structures in the form of wheel loads. However, the findings can also easily be applied to general cases of concentrated block loads on reinforced concrete slabs. In the previous research work on the bearing capacity in shear of reinforced concrete roadway slabs it could be repeatedly stated that the shear bearing capacity of the slabs under single loads is higher than the calculated resistance according to current design rules would expect. Nevertheless, so far no increased bearing capacity could be derived. This discrepancy should be remedied by the present work. After an overview of the field of research and previously performed test series, the research needs and open questions are derived. Based on this, the structural behavior of reinforced concrete slabs under single loads is examined on the basis of large-scale model tests performed at TUHH. From this, one can directly answer many open questions from previous research. In addition, material-non-linear FE simulations are performed to investigate the load transfer of the plates in more detail. The calculations are validated based on the real experiments. It can be shown that the usual fixed relevant design section at the support region is not meaningful, and that the shear forces should be determined close to the concentrated loads. However, these are many times higher than the shear forces at the support of the slab. A hands-on approach to determining the internal forces out of concentrated loads from linearelastic FE calculations is presented and an approach to taking into account the increased load bearing capacity of reinforced concrete slab structures based on the current design equation according to EC2 is proposed. In doing so, the required level of safety in the case of modified proof of the shear bearing capacity is demonstrated by means of a statistical database analysis of selected tests on slabs. It is explained how the direct load transfer of concentrated loads close to the support works phenomenological, and how the failure mechanism of slabs under single loads is related to punching. Finally, it will be shown how the fraction of the inclined compression strut from bending Vccd should be evaluated on haunched slabs.Publicationtype: Doctoral Thesis1064 4251 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Shear Capacity of Concrete Slabs Without Shear Reinforcement Under Concentrated Loads Close to SupportA large number of existing concrete bridge decks in Europe show a deficit of shear capacity according to current design rules. Retrofitting can hardly be done and is very expensive. Thus, new and more reliable design methods are urgently needed. This report describes 8 full-scale tests on cantilever concrete slabs (3.25 × 4.5 m, thickness 0.25 m) without shear reinforcement under concentrated loads. The experimental studies presented in this paper were conducted to get a better understanding of the load bearing behavior of cantilever slabs and to quantify the influence of the direct load transfer of concentrated loads close to line supports.Publicationtype: Conference Paper61 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Versuche zur Querkrafttragfähigkeit von Stahlbetonplatten unter auflagernahen Einzellasten : Versuchsbericht(2017-11-06); Test report on a series of tests on the shear capacity and load transfer of reinforced concrete slabs without shear reinforcement under concentrated block loads.Publicationtype: Technical Report662 504