1. Introduction
Cementitious repair systems form the foundation of all structural rehabilitation works.
They are primarily used to replace deteriorated concrete, restore cover, and regain load-bearing capacity.
They are based on hydraulic binders (cement), enhanced with polymers, fibers, shrinkage-compensating agents, and corrosion inhibitors to provide strong adhesion and durability.
2. Subcategories & Explanation
Type | Description | Typical Use / Area |
Polymer Modified Mortar (PMM) | Cement + polymer blend (SBR / Acrylic). Offers high adhesion, reduced permeability, and good workability. | Patching, cover repairs, honeycomb filling, overhead & vertical repairs. |
Micro-Concrete (Flowable Repair Concrete) | Flowable non-shrink cementitious mix, self-compacting and micro-fiber reinforced. | Jacketing columns, beams, large section loss, congested reinforcement. |
High Strength / Fast-Setting Repair Mortar | Rapid gain of compressive strength, allows early load application. | Runway or plant shutdown repairs, precast repairs. |
Non-Shrink Repair Mortar | Controlled shrinkage for volume stability. | Structural patching in critical zones. |
3. Standards & Testing
Code / Standard | Parameter |
EN 1504-3 | Structural and non-structural repair materials |
ASTM C109 | Compressive strength |
ASTM C348 / C580 | Flexural strength |
ASTM C882 | Bond strength |
IS 516 (Pt 2) | Tensile & flexural strength of concrete |
IS 9103 | Compatibility with admixtures |
4. Performance Parameters (Typical Ranges)
Property | Typical Value |
Compressive Strength | 35–60 MPa |
Flexural Strength | 6–10 MPa |
Bond Strength | ≥1.5 MPa |
Shrinkage | <0.04% |
Layer Thickness | 10–50 mm |
Curing Time | 3–7 days |
5. Quick Selection Guide
Condition | Recommended System |
Small patch repair / cover spalling | Polymer Modified Mortar |
Large volume loss (>25 mm) | Micro-Concrete |
Fast repair (industrial) | Fast-setting mortar |
Overhead / vertical zone | Thixotropic PMM |
Jacketing works | Flowable micro-concrete |