Sökning: "concrete structure"

Visar resultat 1 - 5 av 220 avhandlingar innehållade orden concrete structure.

  1. 1. Hydrophobic Impregnation of Concrete Structures : Effects on Concrete Properties

    Författare :Anders Selander; Johan Silfwerbrand; Jan Trägårdh; Mårten Janz; Andreas Gerdes; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; hydrophobic impregnation; silane; siloxane; concrete; surface treatment; water repellent agent; building protection; impregnering; betong; silan; siloxan; ytbehandling; Civil engineering and architecture; Samhällsbyggnadsteknik och arkitektur;

    Sammanfattning : Hydrophobic impregnations often referred to as water repellent agents, today mainly consisting of alkylalkoxysilanes, are often used on concrete to prolong the service life of the structure. This is accomplished by protecting the reinforcement bars from chlorides or by changing the moisture content inside. LÄS MER

  2. 2. Upgrading concrete bridges : post-tensioning for higher loads

    Författare :Jonny Nilimaa; Luleå tekniska universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Civil engineering and architecture - Building engineering; Concrete; Bridges; Upgrading; Strengthening; Shear; Field testing; Post-tensioning; Prestressing; Samhällsbyggnadsteknik och arkitektur - Byggnadsteknik; Structural Engineering; Konstruktionsteknik;

    Sammanfattning : There are a great number of old structures around the world, some of which were designed for completely different purposes than in their current application. Swedish railway bridges were for example only designed for maximum axle loads of 200 kN in the beginning of the 20th century, while the highest axle loads of today are twice as high. LÄS MER

  3. 3. Hardening concrete : measurments and evaluation of non-elastic deformation and associated restraint stresses

    Författare :Hans Hedlund; Luleå tekniska universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Structural Engineering; Konstruktionsteknik;

    Sammanfattning : If a structural member of hardening concrete is restrained to some degree against expansion and contraction during the heating phase of the hydration process and the subsequent contraction phase, stresses will be induced. The issue of primary interest is whether or not these induced stresses will lead to cracking. LÄS MER

  4. 4. Concrete Bridges : Improved Load Capacity

    Författare :Jonny Nilimaa; Luleå tekniska universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Structural Engineering; Konstruktionsteknik;

    Sammanfattning : There are many beautiful old structures around the world, some of which were designed for completely different purposes than their current applications. For example, Swedish railway bridges were only designed to carry axle loads up to 200 kN in the beginning of the 20th century, while modern loads can be twice as high. LÄS MER

  5. 5. Durability of fire exposed concrete : Experimental Studies Focusing on Sti„ffness & Transport Properties

    Författare :Joakim Albrektsson; Johan Silfwerbrand; Lars Boström; Manouchehr Hassanzadeh; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Concrete; Fire; Polypropylene fibres; Durability; Tunnel; Damage assessment; Ultrasonic pulse velocity; Water absorption; Chloride migration; DIC; Civil and Architectural Engineering; Byggvetenskap;

    Sammanfattning : Road and rail tunnels are important parts of the modern infrastructure. High strength concrete (HSC) is commonly used for tunnels and other civil engineering structures, since it allows high load carrying capacity and long service life. In general, Swedish road and rail tunnels should be designed for a service life of 120 years. LÄS MER