겹침이음 길이를 계산할 때, 철근 간격 cs

In the calculation of bond lengths where only a portion of bars are lapped at a section, clear bar spacing cs is the dimension of concrete between lapped pairs. Figure 13, equivalent to Figure {11.10} in FprEC2, shows dimension cs where 50% of bars are lapped at a section and pairs of lapped bars are in contact.

한 단면에서 철근의 일부만 겹쳐지는 겹침이음 길이를 계산할 때, 철근 간격 cs는 겹쳐진 철근 쌍 사이의 콘크리트 치수를 말합니다. FprEC2의 그림 {11.10}에 해당하는 그림 13은 한 단면에서 철근의 50%가 겹쳐져 있고 겹쳐진 철근 쌍이 접촉하는 경우의 치수 cs를 보여줍니다.

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Design provisions for anchorages and laps in the revised EC2

http://www.hormigonyacero.com/index.php/ache/article/view/3118

Disposiciones de diseño para anclajes y solapes en la revisión del EC2 | Hormigón y Acero

"Fpr" in the context of Eurocodes typically stands for "Final Proposed Document." Eurocodes undergo a process of development and revision, and "Fpr" is used to designate a stage where a document is in its final proposed form before being officially adopted as a standard.

Therefore, "FprEC2" could refer to the Final Proposed Document for Eurocode 2, which is related to the design of concrete structures. It's a stage in the standardization process where the document is considered final but not yet officially adopted.