Author: ACI Innovation Task Group 9
Publisher:
ISBN: 9781945487354
Category :
Languages : en
Pages : 24

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Book Description

Author: Jürgen Grünberg
Publisher: John Wiley & Sons
ISBN: 3433603308
Category : Technology & Engineering
Languages : en
Pages : 251

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Book Description
The wind energy industry in Germany has an excellent global standing when it comes to the development and construction of wind turbines. Germany currently represents the world's largest market for wind energy. The ongoing development of ever more powerful wind turbines plus additional requirements for the design and construction of their offshore foundation structures exceeds the actual experiences gained so far in the various disciplines concerned. This book gives a comprehensive overview for planning and structural design analysis of reinforced concrete and pre-stressed concrete wind turbine towers for both, onshore and offshore wind turbines. Wind turbines represent structures subjected to highly dynamic loading patterns. Therefore, for the design of loadbearing structures, fatigue effects - and not just maximum loads - are extremely important, in particular in the connections and joints of concrete and hybrid structures. There multi-axial stress conditions occure which so far are not covered by the design codes. The specific actions, the nonlinear behaviour and modeling for the structural analysis are explained. Design and verification with a focus on fatigue are adressed. The chapter Manufacturing includes hybrid structures, segmental construction of pre-stressed concrete towers and offshore wind turbine foundations. Selected chapters from the German concrete yearbook are now being published in the new English "Beton-Kalender Series" for the benefit of an international audience. Since it was founded in 1906, the Ernst & Sohn "Beton-Kalender" has been supporting developments in reinforced and prestressed concrete. The aim was to publish a yearbook to reflect progress in "ferro-concrete" structures until - as the book's first editor, Fritz von Emperger (1862-1942), expressed it - the "tempestuous development" in this form of construction came to an end. However, the "Beton-Kalender" quickly became the chosen work of reference for civil and structural engineers, and apart from the years 1945-1950 has been published annually ever since.

Author: Willem Sternberg van Zyl
Publisher: LAP Lambert Academic Publishing
ISBN: 9783659875342
Category :
Languages : en
Pages : 136

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Book Description
Exponential growth of the global wind turbine market has led to a significant increase in the capacity of wind turbine generators. Modern turbines require higher support structures as higher wind speeds combined with longer blades are necessary to increase their generating capacity. The standard 80-90 m tower is thus not economically viable anymore. Transportation logistics of large steel towers has led to concrete towers becoming a viable option. There are currently no design codes dealing exclusively with the design of concrete wind turbine towers. The aim of this project is to investigate and highlight important aspects of the design process of a normally reinforced high strength concrete wind turbine tower. The tower was designed using nonlinear finite element modelling as a design tool to accurately design the tower for various loads and load cases. An analytical design method was developed that can be used in the preliminary design stage. Finally, the importance of the soil-structure interaction was investigated through a sensitivity analysis.

Author: François-Xavier Jammes
Publisher:
ISBN:
Category :
Languages : en
Pages : 146

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Book Description
Ultra-High Performance Concrete (UHPC) has proven an asset for bridge design as it significantly reduces costs. However, UHPC has not been applied yet to wind turbine technology. Design codes do not propose any recommendations or guidance for the towers, thus encouraging the engineer to use less effective traditional materials like steel. The purpose of this thesis is to propose an efficient way to design UHPC wind turbines. First is explained the strategy to retain an optimal design. Then, the comparison with a similar steel model demonstrates that UHPC is both an economical and sustainable design solution for towers. This work is based on a combination of the UHPC 1D model developed at MIT and the interim recommendations provided by Association Franqaise de Genie Civil. The expression of the design loads and the resistant loads for a UHPC circular hollow section are presented based on available design codes. Then, the optimization process based on the previous model is established. It is achieved using two programs in order to satisfy both the Service Limit State (SLS) and the Ultimate Limit State (ULS). The best design is obtained for a SLS criteria deflection of L/800. The cost of material is reduced by a factor between 2 and 3 in comparison with traditional steel. All of this confirms that UHPC could be an innovative engineering solution for the realization of new wind turbine towers.

Author:
Publisher:
ISBN:
Category : Towers
Languages : en
Pages : 1

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Book Description

Author: Michael W. LaNier
Publisher:
ISBN:
Category : Towers
Languages : en
Pages : 698

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Book Description

Author:
Publisher:
ISBN:
Category : Wind turbines
Languages : en
Pages : 53

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Book Description
The current practice for wind turbine foundations is to use massive cast-in-place concrete spread footings or complex pile-supported foundations. Wind turbine generator components and the towers that support them are pre-fabricated and assembled on site, leaving the foundation as the only component of the wind turbine system requiring major in situ construction. The new "hexapod" foundation concept is fully pre-fabricated, uses a fraction of the quantity of concrete used in conventional foundations, and may be dismantled and re-used elsewhere. The wind turbine tower is attached to a steel or concrete hub which is attached to six radial, precast, post-tensioned concrete beams. The hub and beams are transported to the site, assembled, and anchored to the ground using micropiles. The "hexapod" foundation concept was studied in the context of governing design standards and anticipated structural behavior, and a set of design criteria were established. A parametric structural study was conducted to determine the "hexapod" foundation configurations that exhibited the most favorable performance according to the design criteria, and to observe the sensitivity of the foundation’s performance to changes in design properties. Based on the parametric study, recommendations for design and for future study were established.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 1

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Book Description
This fact sheet describes a subcontract with BERGER/ABAM Engineers Inc. to study the economic feasibility of concrete and hybrid concrete/steel wind turbine towers.

Author:
Publisher:
ISBN: 9781904818489
Category :
Languages : en
Pages :

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Book Description
The relative merits and viability of concrete and steel for the wind industry, with practical methods and conceptual configurations for on- and offshore facilities, design philosophies, and construction practices for concrete wind towers; considering fabrication, transportation, installation, maintenance, decommissioning, removal and disposal.

Author: Michael W. LaNier
Publisher:
ISBN:
Category : Towers
Languages : en
Pages : 0

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Book Description