MODULE 9
Development Length, Splices, and Bar Cut Offs
BOND- Defined as the resistance to slipping of
the reinforcing steel bars from the concrete.
DEVELOPMENT LENGTH - Shortest length of
bar in which the bar stress can increase from zero
to the yield strength fy. If the distance from a
point where the bar stress equals to fy to the end
of the bar is less than the development length, the
bar will pull out of the concrete.
HOOKED ANCHORAGES - Are used to provide
additional anchorage when there is insufficient
straight length available to developed a bar.
STANDARD HOOKS
• (db =10mm-25mm--D=6db)
• (db =28mm-36mm--D=8db)
• (db =42mm-58mm--D=10db)
STIRRUP HOOKS
• [6db for 16mm diameter and smaller]
• [12db for 20mm and 25mm diameter]
• [6db for 25mm diameter and smaller]
• [4db for 16mm diameter and smaller]
• [6db for 20mm and 25mm diameter]
Development Length, Splices, and Bar Cut Offs
BOND- Defined as the resistance to slipping of
the reinforcing steel bars from the concrete.
DEVELOPMENT LENGTH - Shortest length of
bar in which the bar stress can increase from zero
to the yield strength fy. If the distance from a
point where the bar stress equals to fy to the end
of the bar is less than the development length, the
bar will pull out of the concrete.
HOOKED ANCHORAGES - Are used to provide
additional anchorage when there is insufficient
straight length available to developed a bar.
STANDARD HOOKS
• (db =10mm-25mm--D=6db)
• (db =28mm-36mm--D=8db)
• (db =42mm-58mm--D=10db)
STIRRUP HOOKS
• [6db for 16mm diameter and smaller]
• [12db for 20mm and 25mm diameter]
• [6db for 25mm diameter and smaller]
• [4db for 16mm diameter and smaller]
• [6db for 20mm and 25mm diameter]
