Worked Examples
Interactive Development-Length Tool
Use the simulation below to reproduce the straight-tension examples. It implements the general metric equation and shows the factor and confinement calculations explicitly.
Controls
Auditable intermediates
- 1.00
- 1.00
- used
- 1.00
- 1.00
- 1.00
- 62.5 mm
- 0.0 mm
- Raw
- 2.500
- Ratio used
- 2.500
Result
Calculated before minimum: 722 mm
Required = 722 mm
Example 1: General Tension Development with the Confinement Cap
Problem: A uncoated bottom bar has and is embedded in normal-weight concrete with . Clear cover is , clear spacing to the adjacent developed bar is , and . Determine the required straight tension development length.
Step-by-Step Solution
0 of 4 Steps CompletedExample 2: Explicit K_tr and an Epoxy-Coated Bar
Problem: Four epoxy-coated bottom bars are developed in normal-weight concrete with and . For the bar being checked, . Two transverse-reinforcement legs cross the potential splitting plane within each spacing. There are developed bars along that splitting plane. The coating condition requires . Determine and .
Step-by-Step Solution
0 of 4 Steps CompletedExample 3: Top-Bar and Epoxy Product Cap
Problem: A top bar has more than of fresh concrete cast below it. It is epoxy coated under a condition that gives . Use , , normal-weight concrete, and a confinement ratio capped at . Determine .
Step-by-Step Solution
0 of 3 Steps CompletedExample 4: Simplified NSCP Table Check for a 25 mm Bar
Problem: A bottom, uncoated bar in normal-weight concrete has and . Its clear spacing and cover satisfy the favorable simplified-table conditions. Determine the simplified development length.
Step-by-Step Solution
0 of 3 Steps CompletedExample 5: Compression Development Length
Problem: Determine the compression development length of a deformed bar with in normal-weight concrete with . No qualifying confinement reduction is taken.
Step-by-Step Solution
0 of 3 Steps CompletedExample 6: Standard 90-Degree Hook in Tension
Problem: A uncoated bar in normal-weight concrete has and . It terminates in a standard hook. The applicable cover conditions permit , but no hook-confinement reduction is taken, so . Determine .
Step-by-Step Solution
0 of 3 Steps CompletedExample 7: A Hook Does Not Repair Compression Development
Problem: A footing dowel carries compression. From Example 5, , but the detail provides only of straight embedment before the bar bends into a hook. Is the dowel adequately developed in compression?
Step-by-Step Solution
0 of 3 Steps CompletedExample 8: Class B Tension Lap Splice
Problem: A permitted tension lap splice has a development length . The provided reinforcement is less than twice that required by analysis and all bars are spliced at the same location. Determine the required splice length.
Step-by-Step Solution
0 of 3 Steps CompletedExample 9: Compression Lap Splice
Problem: Two bars with are lap-spliced in compression. Use the basic NSCP expression for bars not requiring a higher-strength-steel provision and assume no special low-strength-concrete or confinement modifier. Determine .
Step-by-Step Solution
0 of 3 Steps CompletedExample 10: Bundled-Bar Development Increase
Problem: A straight bar has an individual required development length of before the bundled-bar modifier. Determine the required length when that bar is part of (a) a three-bar bundle and (b) a four-bar bundle.
Step-by-Step Solution
0 of 3 Steps CompletedExample 11: Available Footing-Bar Anchorage from the Critical Section
Problem: A square footing supports a square column. Bottom bars have edge cover and a calculated tension development length of . Check straight anchorage from the column face to the bar end.
Step-by-Step Solution
0 of 4 Steps CompletedKeep Force State and Anchorage Type Matched
Straight tension development, hooked tension development, straight compression development, and lap-splice length are different checks. A numerical length from one provision is not interchangeable with another merely because the same bar diameter is involved.