The Tel Aviv Light Rail Green Line is a massive infrastructure project spanning 39 kilometers, connecting Rishon LeZion, Holon, Tel Aviv, and Herzliya. The project included extensive concrete works for at-grade track slabs, maintenance depots, and complex underground stations. To ensure the long-term structural integrity and aesthetics of these massive concrete elements, engineered crack inducers by Maruti were embedded into the slabs and walls to create intentional, controlled weakened planes that direct shrinkage and thermal cracking along neat, predictable lines.
Challenges
Massive Structural Volumes: The project involves casting extensive lengths of unjointed track slabs and deep underground station boxes. Large concrete pours generate high hydration heat, leading to significant thermal contraction and drying shrinkage.
High Water Table & Corrosion: Large sections of the Green Line run through coastal areas with a high water table and high salinity. Random, uncontrolled cracking would create direct paths for water ingress, leading to internal rebar corrosion and structural degradation.
Dynamic Loading: The concrete track slabs must withstand constant, heavy dynamic vibrations and cyclic loads from passing light rail vehicles, which amplifies stress on any existing weak points or micro-cracks.
Solution
Controlled Weakened Planes: Strategically placed PVC or galvanized steel crack inducers were embedded into the concrete during casting. These profiles reduce the effective concrete thickness at precise intervals, forcing cracks to form neatly inside the pre-planned joint rather than randomly across the surface.Integrated
Waterproofing Systems: The crack inducers were paired with hydrophilic waterstops and crystalline waterproofing sealants. This ensures that when the concrete inevitably cracks at the inducer location, the joint remains 100% watertight even under hydrostatic pressure.
Enhanced Asset Lifespan: By shifting stress relief from erratic fractures to engineered joints, the maintenance requirements were successfully minimized, water leakage was eliminated, and the 100-year design life of the transit infrastructure.