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TS 500 development & lap length

Basic development length lb for ribbed bars and the lap length lo, with the 20φ and 300 mm minimums.

Inputs

Bar diameter φmm

fckMPa

fykMPa

Position II (top bars, ×1.4)

Lap factor α1 (§9.2.3)

Results

l_b (formula) [mm]—

20φ [mm]—

Development l_b [mm]—

Lap length l_o [mm]—

Citations

§9.1.2alb = 0.12·(fyd/fctd)·φ ≥ 20φ (ribbed bars).

§9.2.3lo = α1·lb ≥ 300 mm.

VERIFYHand-verified: C25/S420, φ16 → lb=601 mm; formula confirmed across independent sources.

Engine: rc-tr.js v0.1.0 · Code pack: TR-TS500-2000-RC.v1 · Date:

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Preliminary calculation tool. Results are for preliminary sizing and cross-check only. Final design, sealed responsibility, and permit submissions require the full official text of the referenced regulations and the review of a licensed engineer.