Post-installed rebar lap splice design to EN 1992-1-1

AnchorDesign360™ designs reinforcing bars drilled and bonded into existing concrete and lapped with the existing cast-in bars — the connection used when an existing slab, beam, wall or column is extended. The lap is designed with EN 1992-1-1 (Eurocode 2) through EOTA TR 023 and the product’s ETA (EAD 330087): the drilled bar is treated as if it were cast in and checked with the concrete code’s rules for laps and anchorage. It is one of three design modules in the tool — base plate fixings to EN 1992-4, rebar end anchorages to EOTA TR 069, and lap splices to TR 023 — and, like the others, it runs live in the browser with a 3D model and no account.

What you enter

You first pick the application: slab to slab, beam to beam, wall to wall, column to column, or a single rebar. The preset sets up the geometry, and the inputs adapt to it:

• Product and base material — the adhesive product and curing speed, the bar diameter and bar grade f_yk, the existing concrete class and, optionally, the new concrete class, cracked or uncracked concrete, and the working life (50, 100 or 120 years). These select the approved values from the product’s ETA.
• Layout and lap length — the bar grid n_x × n_y, the bonded (lap) length, and the spacings s_x / s_y.
• Covers and joint — the side cover c_x and the top or bottom cover c_y to the bar centre, the bar spacing c_s, the front cover c_f, the cast-in bar diameter and its cover, the new member size, and the interface: an optional interface shear check to EN 1992-1-1 6.2.2/6.2.3 or 6.2.5 (or shear transferred externally by a shear key or dowels), joint roughness (very smooth, smooth, rough, indented), the ΔF_td tension-chord shift, and the most unfavourable tolerance option.
• Transverse reinforcement — an explicit definition of the transverse reinforcement with stirrup diameter, spacing s_b and cover.
• Loads — design for yield, γ_Rd, and the design actions N, V_x, V_y, M_x, M_y.
• Installation — the bond condition (good, η₁ = 1.0, or poor, 0.7).

Inputs the lap route does not use — for example the edge distance fields of the anchorage route — are hidden, so the card shows only what the calculation reads. Each remaining input carries a small ⓘ ring with a plain-language explanation of what the field means and how it changes the result.

What it checks

Because the drilled-in bar is treated as cast-in, the verification follows the lap and anchorage rules of EN 1992-1-1, with the product’s TR 023 / EAD 330087 assessment governing whether and how the mortar may be used that way. The engine reports:

• Lap / anchorage length — whether the bonded length is long enough to develop the bar’s force, including the influence of cover, bar spacing and transverse reinforcement on the required length.
• Steel — the bar itself yielding or breaking.
• Bond — the design bond strength for your concrete class, bond condition, working life and cracked or uncracked condition, taken from the product’s ETA.
• Interface shear at the joint between existing and new concrete, when you switch the check on, to EN 1992-1-1.

For each check the engine works out the resistance, compares it with the acting load and reports the utilisation. The design passes only if every check is at or below 100 %, and the governing mode is called out so you know what is driving the lap. Every result names the clause it came from.

What you get

• Live results and 3D model — the existing and new members, the cast-in bars and the lapped post-installed bars, and the load arrows are the exact geometry being solved, updating together with the results.
• Product comparison — the Comparison panel runs your exact lap against every product in the catalogue, from multiple manufacturers, in one table, using each product’s own ETA data. A product with no lap-splice assessment is reported as not applicable rather than calculated.
• Design-space graphs — resistance against bonded length, with your current length marked, so you can see how much longer the lap needs to be to pass or how much shorter it could be.
• PDF report — the inputs, the geometry, every check with its clause reference, the governing mode and the utilisation, ready to attach to a submission. Exporting the report needs an account; the calculator does not.

No login required to design and compare. An account is needed only to export the PDF report.

Frequently asked questions

The software supports, but does not replace, the judgement of a qualified structural engineer. Always confirm the design against the current issue of the product’s ETA.