Product Overview

MC-Injekt 2K PU is the rigid structural crack injection resin in the MC-Bauchemie injection product range — designed for the specific application of re-bonding cracks in structurally loaded concrete members where the crack has compromised the tensile or shear load-carrying capacity of the section and the repair objective is to restore the original structural continuity, not merely to waterproof the crack. The two-component chemistry (isocyanate Component A and polyol Component B) reacts upon mixing in the injection packer and within the crack to produce a rigid polyurethane polymer with compressive strength of 50 to 70 MPa and tensile strength of 15 to 25 MPa — substantially matching or exceeding the tensile and compressive strength of the parent C30 to C50 structural concrete and enabling the injected crack to transfer tensile and shear stresses across the interface once the resin has cured. The low initial viscosity of MC-Injekt 2K PU (300 to 600 mPa.s at 25 degrees Celsius, similar to a heavy oil) is critical for the fundamental penetration requirement of crack injection: the resin must flow under the applied injection pressure (0.5 to 5 bar) into cracks as narrow as 0.1 to 0.2 mm to achieve complete void-filling of the crack plane; high-viscosity materials cannot penetrate fine cracks and leave air voids within the crack that prevent structural re-bonding. The tolerance for damp crack surfaces (not flowing water — use MC-Injekt 1K for active water ingress) expands the practical applicability of MC-Injekt 2K PU to the very common situation in Indian below-grade concrete construction where cracks in basement retaining walls and raft slabs may not be actively leaking but are slightly damp from contact with groundwater on the positive side. Space Arc Engineering supplies MC-Injekt 2K PU for structural crack repair in basement construction, retaining walls, bridge substructure repair, and building foundation repair in Ghaziabad, Noida, Delhi, and Uttar Pradesh.

Applications

• Structural re-bonding of flexural cracks in concrete beams and slabs — injection of dormant (non-moving, thermally or structurally stable) flexural and shear cracks in reinforced concrete beams, slabs, and frames in existing buildings and structures in Delhi NCR and Uttar Pradesh where crack survey, structural assessment, and crack movement monitoring have confirmed that the crack is stable and no longer actively opening under service loads (a prerequisite for rigid resin injection — injecting a moving crack with rigid resin will cause the resin to re-crack adjacent to the injection line when the crack moves again); the injection of rigid MC-Injekt 2K PU into confirmed stable flexural cracks 0.2 to 1.5 mm width in concrete beams and slabs re-establishes the concrete tensile continuity across the crack plane and restores the member to its uncracked flexural and shear capacity; the structural engineer must review the crack survey and confirm structural re-bonding as the correct repair principle before specifying MC-Injekt 2K PU injection (crack sealing with a flexible sealant is the correct approach for moving or thermally active cracks)
• Crack injection in basement retaining walls and raft slabs for waterproofing and structural re-bonding — injection of dormant vertical and diagonal cracks in basement retaining walls and horizontal cracks in raft foundation slabs in below-grade construction in Delhi NCR and Greater Noida where cracks have formed during the early-age thermal contraction and shrinkage of the concrete (common in 500 to 800 mm thick raft slabs) or during initial loading of the retaining wall; these cracks are typically water-ingress paths and structural weaknesses requiring simultaneous waterproofing and structural repair; MC-Injekt 2K PU achieves both objectives in a single injection operation by filling the crack with rigid, impermeable, waterproof polyurethane resin that bonds the crack faces (structural re-bonding) and seals the water ingress path (waterproofing) — dual performance that neither cementitious injection (EN 1504-5 P-type, principle 4.4) nor flexible sealant can simultaneously provide in a single operation
• Structural concrete crack repair in bridge piers, beams, and deck slabs on national highways and urban infrastructure — injection of dormant cracks in prestressed and reinforced concrete bridge elements (PSC girders, bridge deck slabs, pier caps, and abutment walls) during bridge rehabilitation and maintenance operations on NHAI national highways, PWD state highway bridges, and urban flyover viaducts in Delhi NCR and Uttar Pradesh; bridge structural crack repair specifications typically reference EN 1504-5 or the Indian Roads Congress IRC:58 / IRC:SP:40 repair guidelines and require rigid, high-strength crack injection to restore the structural integrity of cracked bridge elements; MC-Injekt 2K PU with its minimum 50 MPa compressive strength and EN 1504-5 compliance meets these specifications for structural crack injection in bridge elements

Key Advantages

• Two-component mixing at the injection packer for precise stoichiometric ratio control and reliable cure — the two-component system of MC-Injekt 2K PU mixes Components A and B at the injection packer tip in the factory-set mixing ratio (typically 1:1 or 2:1 by volume via a calibrated dual-cartridge injection gun with static mixer tip), ensuring the correct polyurethane reaction chemistry and complete cure within the crack; this is more reliable than site-measured single-component systems and ensures consistent post-cure mechanical properties throughout the crack injection; the static mixer tip provides homogeneous blending of the two components in the sub-second mixing time available before injection into the crack — the mixing geometry is the critical quality assurance element that MC-Bauchemie factory engineering provides in the product cartridge design, not a site variable
• EN 1504-5 compliance for structural re-bonding (Principle 4, Method 4.5) with documented performance data for structural engineer specification — MC-Injekt 2K PU is assessed and classified under EN 1504-5, the European standard for concrete crack injection products and systems, providing the structural engineer, specification writer, and building owner with independent third-party verification of the product performance for the specific intended use of structural re-bonding; the EN 1504-5 performance data includes tensile adhesion, compressive strength, flexibility, reaction to fire, and expansion characteristics measured by standardised test methods — enabling the structural engineer to specify MC-Injekt 2K PU in the repair specification with measurable, verifiable performance requirements rather than relying on manufacturer claims only