Since the Second World War the demand of energy has undergone an exponential growth that has led to a sharp annual increase in the use of natural gas in both, cities and thermal power stations. Nowadays, the strategic relevance of natural gas as a main source of energy is evident with a contribution of more than 20% of the total world consumption. This development in increasing demand of natural gas has led for a need of suitable storage and transportation infrastructure. Various gases, especially hydrocarbons, are preferably stored in liquid form for transportation and storage since the phase transformation from gas to liquid comes with a significant reduction of the volume (e.g. up to 600 times). Gases can be liquefied by raising the pressure or by cooling to their boiling point, which for most gases is below 0°C. This is known as cryogenic storage. The term cryogenic is derived from two Greek words, namely kryos meaning icy-cold and genes which can be translated as shape. These fib recommendations are concerned about post-tensioning systems used in cryogenic tanks and have been formulated on the basis of actual available knowledge with the aim to reflect the current state of the art. Consequently, these recommendations have included a classification of the different cryogenic tanks typologies used in the past and nowadays, the associated different tendon types depending on their exposure to low temperature (e.g. never, only accidentally or during normal tank operation) and the testing regime required for acceptance of the materials and the post-tensioning system according to this document. An international working group comprising more than 20 experts from administrative authorities, universities, laboratories, owners, structural designers, suppliers of prestressing steels and post-tensioning systems suppliers have actively contributed in order to develop these recommendations. This text has been written to cover best construction practices around the world, and to provide material specifications which are considered to be the most advanced available at the time of preparing this text. For ease of use (for Owner, Designer and Post-tensioning System Supplier), the content has been arranged systematically according to the system components into chapters focusing on performance characteristics, requirements and acceptance criteria.
The book combines history with academic notes for use at the university level, presenting design examples from actual jobs with applications and detailing for the practicing engineer. Chapter 1 tells the history of post-tensioned concrete as only Ken Bondy can tell it. Chapters 2-8 are the notes Dirk Bondy uses to teach Design of Prestressed Concrete Structures at UCLA and Cal Poly-San Luis Obispo. Chapters 9-13 are design examples that address many of the decisions faced by practicing engineers on typical projects. Chapters 13-14 cover the art of detailing and observing the construction of post-tensioned concrete. This knowledge was obtained over many years of working on our own projects and listening and learning from the the pioneers of post-tensioned concrete. Chapter 15 covers the slab on grade industry, which represents more sales of post-tensioning tendons than all other post-tensioning applications combined. Chapter 16 discusses the challenging application of post-tensioning-external post-tensioning.
This manual contains updated information on the current practices in the use, design, and construction of post- tensioning. The 6th Edition has been extensively rewritten and expanded from the 5th Edition. The Manual contains 12 new chapters that give design guidance on modern applications of post-tensioning. All of the original chapters have been totally revised and modified to reflect the current industry practices. New topics include Seismic Design, Post-Tensioned Concrete Floors, Parking Structures, Slab-on-Ground, Bridges, Stay Cables, Storage Structures, Barrier Cables, Dynamic and Fatigue, Durability, Inspection and Maintenance, and Field and Plant Certification. The Manual provides the industry standard for design and construction of post-tensioned structures. This book is an invaluable resource for practicing engineers, architects, students, educators, contractors, inspectors, and building officials. The 6th Edition of the Post-Tensioning Manual provides basic information and the essential principles of post-tensioning.
This volume highlights the latest advances, innovations, and applications in the field of FRP composites and structures, as presented by leading international researchers and engineers at the 10th International Conference on Fibre-Reinforced Polymer (FRP) Composites in Civil Engineering (CICE), held in Istanbul, Turkey on December 8-10, 2021. It covers a diverse range of topics such as All FRP structures; Bond and interfacial stresses; Concrete-filled FRP tubular members; Concrete structures reinforced or pre-stressed with FRP; Confinement; Design issues/guidelines; Durability and long-term performance; Fire, impact and blast loading; FRP as internal reinforcement; Hybrid structures of FRP and other materials; Materials and products; Seismic retrofit of structures; Strengthening of concrete, steel, masonry and timber structures; and Testing. The contributions, which were selected by means of a rigorous international peer-review process, present a wealth of exciting ideas that will open novel research directions and foster multidisciplinary collaboration among different specialists.
These recommendations present a guide to the design of two-way spanning, post-tensioned concrete flat slabs using unbonded or bonded tendons. Recommendations purely related to the use of unbonded tendons are clearly marked. These recommendations are intended only for the design of post-tensioned flat slabs in buildings and do not include the use in bridges. Post-tensioned concrete construction can be defined as unbonded or bonded, depending on whether the tendon ducts are filled with a cement grout (in order to provide a bonded structure) or whether the tendons are suitably coated and wrapped or greased and plastic covered (unbonded). While in a number of countries, (e.g., United States and Canada) economic and construction considerations have resulted in the selection of unbonded tendons, in other countries the use of the traditional bonded tendons is favoured, (e.g., Australia). Some of the advantages claimed for the use of unbonded tendons can be summarized as follows: Extremely low friction values, tendons are fully protected against corrosion during construction, maximum possible tendon drape due to the small diameter of the tendon; this is of major importance in slender structures such as flat plates, simple and fast placement of the tendons, avoidance of grouting operations. When tendons are grouted after stressing the claimed advantages are particularly that the bond between the concrete structure and the tendons increases the ultimate strength and less reliance is placed on the long-term adequacy of the anchorage.