BE95-1347 Probabilistic Performance Based Durability Design of Concrete Structures
With the present design approach with respect to the durability of concrete the building industry is hardly able to compete. Possibilities for competition on basis of durability with other designs of structures made of concrete or other structural materials, such as steel, timber or masonry is extremely limited. The consortium for the proposed research is convinced that a performance based design provides this option, as it uses realistic environmental and material models capable to predict the future behaviour of a concrete structure and hence quantifies the design life.
The present design approach with respect to durability of concrete structures is for a large extent empirical. It is based on deem-to-satisfy rules (e.g. minimum cover, maximum water/cement ratio) and the assumption that if these rules are met, then the structure will achieve an acceptably long but unspecified life. Improving the durability may result in increasing building costs but cannot, but current design methods do not permit the whole life cycle costs to be defined. There is thus no means for demonstrating that future maintenance and repair costs will reduce.
The result of the project will be design methodology with the following benefits:
- durability design will be based in the same principles as structural design (safety, serviceability, limit states and reliability)
-design based on the total life cycle costs will be possible -a reduction of the consumption of materials and energy by optimal use of the materials
-objective basis for consultants, contractors and maintainers to make tailor made designs, especially if the design is based on industry specific material properties
-realistic performance test procedure to establish the material behaviour -methodology can be extended to new materials and new applications.
Optimization of the durability has also positive environmental impacts. It leads to a reduction in the consumption materials and energy due the possibility to design for a longer use. Furthermore the prediction of the service life will be more reliable resulting in less premature demolitions of concrete structures. Sustainable building involves the re-use of building materials, waste materials and new types of material. Only the framework of a performance based design procedure offers an objective basis for the prediction of the in service behaviour of these new materials.
Funding SchemeCSC - Cost-sharing contracts
412 96 Goeteborg
3870 CB Hoevelaken
6130 PD Sittard
2600 AA Delft
3502 LA Utrecht
UB1 2QX Southall