A new model for anchorage length design in concrete elements considering support effects and ductility

Understanding the phenomena that play a crucial role in the support of (precast) elements is crucial for the production and application of concrete elements. A lively debate is still ongoing about how it should work and how it seems to work in practice, where neither supports the other. Numerous examples of well-performing elements exist where the 10Ø or 100 mm criterion is not fulfilled, and exceptions are introduced by product standards, illustrating our lack of understanding. In the context of the introduction of a new national annex to EN 1992-1-1 (2023) in Belgium, a research project was launched to provide complementary information. A new analytical model and a new test setup have been developed, leading to a better understanding. Results of the tests support the proposed model based on a slip modulus. Based on the outcomes, significantly reduced anchoring lengths can be used.