Dynamic loads have historically not been a troubled area for concrete floors, foremostbecause of the high self-weight compared to the dynamic load. With new technical andcalculation achievements during the last decades concrete floors have become longerand more slender. This have led to more open plan structures with longer spans thatmake concrete floors more sensitive to vibrations.This thesis studies the dynamic effects of hollow concrete core elements induced by co-ordinated jumping and the vibration levels that spread to the floor above. The thesisinvestigates different standards and guides on how to perform a dynamic analysis andevaluate it. In the thesis an experiment was conducted on WSP Sweden headquar-ters in Stockholm. The fifth and sixth floor of the building was investigated in thisthesis. The floors are made of hollow concrete core elements of the type HD/F 120/27.First a so-called heel drop test was done on the fifth floor to evaluate the naturalfrequency of the floor. The floors were monitored while 12 people performed coordi-nated jumping. Three accelerometers were placed on the fifth floor where the load wasapplied and one on the floor above.The results from the experiment and simulation were evaluated with three methodsISO 10137, National Building Code of Canada and Design Guide - Floor VibrationsDue to Human Activity. The data from the experiment shows that the upper floor isunsuitable for office use for 2 standards. The lower floor is viewed as acceptable formore carefree setting such as shopping malls.A finite element analysis of the building was done in the program Brigade. The modelconsists of one wing of the building and the fifth and sixth floor. The remaining floorsare modelled as equivalent mass. The columns were modeled down to the fourth floorand the beams for the fifth and six floors were included. A stairwell between the fifthand sixth floor was also modelledEvaluation of the finite element results was done in the same fashion as the experi-ment. Here the upper floor was performing satisfactory for office use and the lowerfloor was similarly as the experiment above accepted for settings where more acceler-ation is considered acceptable such as for restaurants and shopping malls.The maximum transient vibration value (MTVV) results from the experiment andsimulation was compared and the lower floor was conforming pretty well with a dif-ference smaller than 1 % to around 30 % depending on the accelerometer. However,the results for the upper floor differs significantly, as the difference is about 770 %between the experiment and simulation. The finite element model is not able to ac-curately represent the real building for the acceleration of the upper floor. This couldbe explained by the the absence of partition walls for meeting rooms, copying room,toilets and the facade. Since this could limit the acceleration that is transmitted fromthe lower floor to the upper floor.

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no / The design of multi-storey buildings in the UK, in the past, considered steel and concrete structures in isolation. Today, designers utilize the combined properties of steel and concrete in the form of composite or hybrid structures as a more attractive efficient alternative. Designers of steel structures acknowledge that the presence of concrete slabs may be designed compositely with steel beams in order to increase both flexural strength and stiffness at virtually no extra cost, except for the headed shear studs. The use of composite construction with precast hollowcore slabs has become one of the most popular construction methods in the UK. Currently, design of composite construction is covered by BS5950, Part 3, but will soon be replaced by the new European Standard, Eurocode 4. However, design of composite construction with precast hollowcore slabs is currently outside the provisions of this new code. In this paper, an overview of the Eurocode 4 structure and its contents are first presented and some of the particular issues that affect this new form of construction will be given. Design guidance using the Eurocode methodology will also be presented.

No / Composite structure incorporating steel beams and precast hollowcore slabs is a recently developed composite floor system for building structures. This form of composite construction is so far limited to simple beam-column connections. Although the concept of semi-rigid composite joints has been widely research in the past, most of the researches have been carried out on composite joints with metal deck flooring and solid concrete slabs. Research on composite joints with precast hollowcore slabs is rather limited. As the construction industry demands for rapid construction with reduction in cost and environmental impacts, this form of composite floor system, which does not require major onsite concreting, has become very popular among the designers and engineers in the UK. In this paper, full-scale tests of beam-to-column semi-rigid composite joints with steel beam and precast hollowcore slabs are reported. Based on the tests data; the structural behaviour of these semi-rigid composite joints is discussed together with numerical and finite element modelling. Through parametric studies, an analytical model for the semirigid composite joints is proposed and is verified by both the experimental data and finite element model; and good agreement is obtained.

The full-width, full-depth precast panel system is very convenient for rehabilitation of deteriorated decks as well as for new bridge construction. The horizontal shear strength at the interface between the two interconnected elements is of primary importance in order to provide composite action. The strength of the bond between the two precast members should be high enough to prevent any progressive slip from taking place. Flexural strength, shear strength and deflection characteristics all depend on the satisfactory performance of the interface to provide composite action. However, the case when both of the interconnected elements are precast members bonded by means of grout, is not currently addressed by ACI or AASHTO. This is the main impetus for this project. A total of 36 push-off tests were performed to develop a method for quantifying horizontal shear strength and to recommend the best practice for the system. Test parameters included different haunch heights, different grout types, different amount and different type of shear connectors. Two equations, for uncracked and cracked concrete interfaces, are proposed to be used in horizontal shear design when the precast panels are used. Predictive equations are compared with available methods for the horizontal shear strength of the precast panel system. Conclusions and recommendations for the optimum system are made. / Master of Science

Thesis (M.E.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references. Also available via the World Wide Web.

no / Precast concrete floors are widely used in building construction, but there is little detailed design guidance on their application in steel-framed buildings. Traditionally the steel beams have been designed to support the precast slabs on their top flange. However, there are an increasing number of composite frames and slim floor constructions where the precast slabs are designed to interact structurally with the steel frame. Composite action can be developed by welded shear connectors attached to the steel beams and by transverse reinforcement; however, this form of construction is currently outside the provisions of the current codes of practice. This paper discusses some of the particular issues that affect this form of construction, and presents design guidance using the Eurocode methodology.