TY - GEN
T1 - Benchmark for deemed-to-satisfy rules
AU - Von Greve-Dierfeld, S.
AU - Gehlen, Ch
N1 - Publisher Copyright:
© 2014, Universities Press (India) Private Limited. All rights reserved.
PY - 2014
Y1 - 2014
N2 - The current system for specifying and ensuring durability of new concrete structures in standards is commonly of a prescriptive type. In prescriptive specifications, durability is guaranteed indirectly by ensuring compliance with limiting values for concrete composition and construction details. These empirical provisions have typically evolved from local experience and the local availability of concrete constituents. They are based on the individual preferences on safety without any type of mathematical or scientific verification. One of the practical results is that there is an enormous variation in requirements between the various countries all over the world and even in Europe when close regional proximity is given. However, the different national provisions cannot be explained on a rational basis and it is likely that they do not lead to a consistent exposure resistance. The aim of this work is to perform a benchmark for deemed-to-satisfy rules for the exposure classes XD and XS. Within the benchmark, it is determined which reliabilities against chloride-induced depassivation of rebars can be expected if the deemed-to-satisfy rules of different countries are considered. This includes not only calculations mainly based on short term laboratory data, but also an independent assessment of existing structures. The calculated reliability ranges determined are compared with the target reliabilities proposed by current specifications and, based on the above comparison, a proposal for improving deemed-to-satisfy rules and specifications is made.
AB - The current system for specifying and ensuring durability of new concrete structures in standards is commonly of a prescriptive type. In prescriptive specifications, durability is guaranteed indirectly by ensuring compliance with limiting values for concrete composition and construction details. These empirical provisions have typically evolved from local experience and the local availability of concrete constituents. They are based on the individual preferences on safety without any type of mathematical or scientific verification. One of the practical results is that there is an enormous variation in requirements between the various countries all over the world and even in Europe when close regional proximity is given. However, the different national provisions cannot be explained on a rational basis and it is likely that they do not lead to a consistent exposure resistance. The aim of this work is to perform a benchmark for deemed-to-satisfy rules for the exposure classes XD and XS. Within the benchmark, it is determined which reliabilities against chloride-induced depassivation of rebars can be expected if the deemed-to-satisfy rules of different countries are considered. This includes not only calculations mainly based on short term laboratory data, but also an independent assessment of existing structures. The calculated reliability ranges determined are compared with the target reliabilities proposed by current specifications and, based on the above comparison, a proposal for improving deemed-to-satisfy rules and specifications is made.
KW - Assessment of existing structures
KW - Chloride
KW - Deemed-to-satisfy rules
KW - Durability
KW - Performance based rules
KW - Reliability design
UR - http://www.scopus.com/inward/record.url?scp=85011928396&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:85011928396
T3 - 4th International fib Congress 2014: Improving Performance of Concrete Structures, FIB 2014 - Proceedings
SP - 300
EP - 302
BT - 4th International fib Congress 2014
PB - Universities Press (India) Private Limited
T2 - 4th International fib Congress, FIB 2014
Y2 - 10 February 2014 through 14 February 2014
ER -