Sika Sikadur-31 SBA S-03 IN
Two-component, solvent-free epoxy jointing adhesive for match-cast bridge segments, formulated for site temperatures between +15C and +35C.
What is it?
A two-part, moisture-tolerant epoxy paste adhesive from Sika, purpose-made to glue precast concrete bridge segments together into a structural, watertight joint. The S-03 grade is set for a +15C to +35C working window.
Where is it used?
Precast segmental construction of metro viaducts, elevated corridors, flyovers and span-by-span box-girder bridge decks, where match-cast segments are erected and stressed together.
Why use it?
It lubricates the segment faces for easy positioning, transfers compressive and shear load across the joint, seals it against water, and hardens without shrinkage while tolerating damp concrete.
How is it applied?
Both parts are pre-batched; mix Part A and Part B (3:1 by weight) for about four minutes, trowel onto prepared segment faces, then draw the segment up and post-tension within the open time.
About Sika Sikadur-31 SBA S-03 IN
Sikadur-31 SBA S-03 IN belongs to Sika’s segmental bridge adhesive family, a group of epoxy pastes engineered specifically for the moment a precast bridge segment is match-cast, lifted into place and glued to the segment behind it. On a segmental job the adhesive does three jobs at once: it acts as a lubricant so the shear keys slide together cleanly, it fills the hairline gaps to make the joint watertight, and once cured it becomes a load-transferring layer that carries compression and shear across the interface. The “SBA” designation is Sika’s shorthand for Segmental Bridge Adhesive, and the “S-03” suffix identifies the temperature grade tuned for ambient and substrate conditions of +15C to +35C, which covers most of the year across Delhi NCR, the northern plains and hill-country sites.
The wider product line runs from S-04 IN for cool conditions (+10C to +20C) up through S-09 IN for hot weather (+20C to +50C), so the specifier picks the grade whose pot life and open time match the deck temperature on the day of erection. Choosing S-03 for a mild-weather pour, rather than a hot-weather grade, keeps the pot life and open time workable so the crane crew has enough time to butter the faces, offer the segment up and stress it before the epoxy stiffens. Because the product is thixotropic and non-sag it holds on vertical and overhead faces without a primer, and because it is moisture tolerant it bonds to concrete that is dry or matt-damp, a real advantage on Indian sites where segments are rarely bone dry.
The technical insight
The adhesive is built on an epoxy resin filled and thixotroped so it behaves as a non-sag paste yet still squeezes to a thin, even film under post-tensioning load. Two things make it work on a segmental joint. First, the epoxy chemistry cures by a cross-linking reaction that is driven by the hardener rather than by drying or by loss of solvent, so hardening is unaffected by humidity and the film keeps developing strength even against a matt-damp face. Second, the formulation is deliberately high-modulus: the cured layer reaches an instantaneous modulus of elasticity of around 14,000 N/mm2, close to the stiffness of the surrounding concrete, so the glue line does not become a soft spot that concentrates strain. Compressive strength climbs fast, reaching at least 60 N/mm2 at 24 hours and at least 75 N/mm2 at 7 days, while shear strength reaches at least 12 N/mm2 at 7 days, and tensile-adhesion tests on wet concrete fail in the parent concrete rather than the bond line. The temperature grading matters because pot life and open time shorten as the mix warms; the S-03 grade is balanced so that within its +15C to +35C window the crew retains enough working time, whereas a hotter grade at the same temperature would be too generous and a cooler grade too sluggish to cure.
Where it is used
- Jointing match-cast precast segments in span-by-span and balanced-cantilever bridge decks
- Erection of box-girder segments for metro and rail viaducts
- Elevated road corridors and flyover superstructures built segmentally
- Forming watertight, load-transferring joints between post-tensioned segments
- Bonding shear-keyed faces where the adhesive must also lubricate positioning
- Structural bonding of precast concrete elements in mild-weather site conditions
- Segmental pier and hollow-column construction requiring epoxy jointing
- Projects specifying compliance with FIP/fib acceptance criteria for segmental adhesives
Key advantages
- Moisture tolerant, bonds reliably to dry or matt-damp concrete common on Indian sites
- High modulus (~14,000 N/mm2) so the glue line matches concrete stiffness and transfers load
- Rapid strength gain, at least 60 N/mm2 compressive at 24 hours for early stressing
- Thixotropic and non-sag on vertical and overhead faces, no primer required
- Lubricates shear keys, making segment positioning and closure easier for the crane crew
- Solvent-free and hardens without shrinkage, so the joint stays dimensionally stable
- Impermeable to liquids and water vapour, giving a genuinely watertight joint
- Contrasting Part A and Part B colours give a visual check that mixing is complete
Limitations & considerations
- Temperature-locked: S-03 suits +15C to +35C only, other grades are needed outside that band
- Short working window, pot life is roughly 35 minutes so only mix what can be placed in time
- For experienced professionals only, not a general-purpose site adhesive
- Substrate must be at least 3C above dew point or condensation will compromise the bond
- Concrete must be 28 days old, abrasive-blasted and laitance-free before application
- Long-term structural design load must allow for epoxy creep, typically kept below 20-25% of failure load
Selection & best practice
Confirm the deck and ambient temperature fall inside the +15C to +35C band before choosing S-03; if a cold morning or a hot afternoon is expected, switch to S-04 IN or S-09 IN so pot life and cure stay in range. Prepare 28-day-old concrete by abrasive blasting to an open, laitance-free texture and remove all dust. Check the substrate is at least 3C above dew point. Mix full pre-batched units only: stir Part A, add Part B (3:1 by weight), and mix for about four minutes to a uniform grey with no streaks, avoiding over-mixing that entrains air. Trowel the paste onto both faces, working it well into a matt-damp surface, then offer the segment up and apply post-tensioning within the open time. Do not open the next unit until the previous one is placed, and clean tools with Sika Colma Cleaner before the epoxy cures, as hardened material can only be removed mechanically.
Specifications
| Chemical base | Two-part epoxy resin with selected fillers |
| Mixing ratio | Part A : Part B = 3:1 by weight |
| Application temperature range | +15C to +35C (substrate and ambient) |
| Pack size | Pre-batched 6 kg unit (Part A 4.50 kg + Part B 1.50 kg) |
| Density (mixed) | 1.9 +/- 0.1 kg/L at +30C |
| Maximum layer thickness | 30 mm |
| Compressive strength | >=60 N/mm2 at 24 h; >=75 N/mm2 at 7 days |
| Shear strength | >=12 N/mm2 at 7 days |
| Modulus of elasticity | ~14,000 N/mm2 (instantaneous, in compression) |
| Shelf life / storage | 12 months, stored dry at +5C to +40C, out of direct sun |
Industry use cases
Metro & Rail Viaducts
Gluing match-cast box-girder segments during span-by-span erection of elevated metro and rail corridors, where each joint must transfer load and stay watertight for decades.
Flyovers & Elevated Roads
Segmental jointing of urban flyover and elevated-road superstructures, letting contractors erect and stress segments quickly in mild-weather windows.
Highway Bridges
Balanced-cantilever and span-by-span highway bridge decks where precast segments are bonded into a continuous, post-tensioned structure.
Precast Infrastructure
Casting-yard and site bonding of precast piers, hollow columns and deck units on large infrastructure programmes needing FIP-compliant adhesives.
Consultant & PMC Specification
A grade-specific epoxy that consultants and project-management teams can specify by temperature window, ensuring pot life and cure suit the erection schedule.
Frequently asked questions
What does the S-03 in Sikadur-31 SBA S-03 IN actually mean?
Can it be applied to damp concrete?
How long is the working time once mixed?
What pack size does it come in and what is the mixing ratio?
How soon can the segments be stressed after gluing?
Is it available in Delhi NCR and across India?
How we position Sika Sikadur-31 SBA S-03 IN
Within the Sika range, choose the temperature grade that matches your site: Sikadur-31 SBA S-04 IN for cool conditions (+10C to +20C) or Sikadur-31 SBA S-09 IN for hot weather (+20C to +50C), keeping S-03 IN for the +15C to +35C window. Clean uncured adhesive from tools with Sika Colma Cleaner. For segment surface preparation and structural bonding on other elements, the wider Sikadur epoxy range applies. Where a project is specified around Fosroc rather than Sika, our Fosroc Nitobond SBA is the direct equivalent segmental bridge adhesive; and for allied concrete-repair scope we also carry Dr. Fixit, MC-Bauchemie and Master Builders Solutions systems.
Fosroc Nitobond SBA — Specify the Fosroc option when the project’s approved-vendor list or client standard is built around Fosroc, as Nitobond SBA is its directly equivalent epoxy segmental bridge adhesive.
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