Structural Calculator

Rebar Splice Calculator

Compute tension and compression lap splice lengths for deformed reinforcing bars per ACI 318-19M Section 25.5. All modification factors (ψt, ψe, ψs, ψg, λ) applied automatically.

ACI 318-19M · §25.5 · SI Units

What This Calculator Can Do

A complete lap splice design toolset for deformed reinforcing bars in tension and compression.

Tension Lap Splice (Class A & B)

Class A (1.0 ld) and Class B (1.3 ld) tension splices per ACI 318-19M Table 25.5.2.1.

Compression Lap Splice

Compression splice lengths per ACI 318-19M Section 25.5.5 with fy- and f'c-based minimums.

All Modification Factors

ψt top bar, ψe epoxy, ψs size, ψg grade, and λ lightweight applied per ACI 25.4.2.

Concrete Strength Correction

Automatic √f'c cap and correction for concrete with f'c < 21 MPa.

Bar Sizes 10M–36M

Full metric rebar range: 10M, 15M, 20M, 25M, 30M, and 36M deformed bars with accurate db values.

Steel Grades 400–520 MPa

Supports Grade 400, 420, 500, and 520 MPa reinforcement with the grade factor ψg applied automatically.

Minimum/Maximum Length Enforcement

Applies the 300 mm tension minimum and all compression splice lower bounds per the code.

Step-by-Step Computation Trace

Full derivation of ld and ls with every factor, ratio, and governing limit shown transparently.

SI Units (mm, MPa)

Consistent metric output in millimetres and megapascals for international engineering practice.

How It Works

From bar selection to a fully traced splice length in four simple steps.

1

Select Bar Size & Grade

Pick the deformed bar size (10M–36M) and steel grade (400–520 MPa) being spliced.

2

Enter Concrete f'c

Input the specified concrete compressive strength; the calculator applies the √f'c cap automatically.

3

Choose Splice Class

Select Class A or Class B for tension, or compression splice, and set top-bar, epoxy and lightweight options.

4

Get Length With Full Trace

Read the governing splice length together with a complete step-by-step computation report.

Standards & Codes

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