About Fosroc Structuro 352

Fosroc Structuro 352 is a high-performance, liquid superplasticising admixture engineered to reduce the water demand of concrete while keeping it highly workable. It belongs to Fosroc’s Structuro family of high-range water reducers, a category of admixtures that has become central to modern Indian concrete practice as the country’s construction sector shifts from site-mixed concrete towards controlled ready-mix (RMC) production. For a contractor or a batching-plant operator, the value proposition is straightforward: you can drop the water content of a mix significantly, hold the slump you need for placing and pumping, and end up with denser, stronger and more durable concrete.

The reason water reduction matters so much comes down to the water-cement ratio. Excess mixing water leaves behind capillary pores once the concrete hardens, and those pores are the pathways through which chlorides, sulphates and moisture attack reinforcement. By letting the producer cut water without losing flow, Structuro 352 helps achieve the low w/c ratios that durability codes such as IS 456 demand for aggressive exposure conditions, common in coastal Mumbai and Chennai projects, in sewage and effluent structures, and in the high-sulphate soils found in parts of western and central India.

What sets Structuro 352 apart within the range is its robustness. Fosroc positions it as a stable, forgiving admixture that avoids large swings in workability when small amounts of extra water find their way into a mix, a practical reality at busy plants and on long-haul transit-mixer deliveries through Indian traffic. It is designed as a single-product admixture for ready-mixed plant concrete and is also suited to the manufacture of wet sprayed concrete (shotcrete), making it relevant to tunnelling, slope stabilisation and repair work. As an authorised Fosroc distributor serving Delhi NCR and Pan-India, Space Arc Engineering supplies Structuro 352 alongside technical guidance on trial mixes and dosage optimisation.

The technical insight

Structuro 352 conforms to EN 934-2:2010 Tables 3.1 and 3.2, the European benchmark for high-range water-reducing/superplasticising admixtures, and carries a water-soluble chloride content of no more than 0.10% by mass, which classifies it as effectively chloride-free and therefore safe for use in steel-reinforced and prestressed concrete. Its alkali content is held to a maximum of around 2.5% Na2O equivalent by mass, an important figure where alkali-aggregate reactivity is a concern with certain Indian aggregates. The admixture works by deflocculating cement particles so that the water trapped between them is released for lubrication; this is what allows the same workability to be achieved at a markedly lower water content, or much higher fluidity at constant water. Crucially, dosage is governed by performance, not by a fixed rule, so site trials with the actual cement, fly ash/GGBS and aggregates are essential before production.

Where it is used

• Ready-mixed (RMC) plant concrete as a single-product superplasticiser
• High-strength and high-performance structural concrete for columns, cores and transfer slabs
• Pumped concrete where high fluidity must be maintained over long delivery and pumping distances
• Wet sprayed concrete (shotcrete) for tunnel linings, slope stabilisation and repair
• Durable concrete for aggressive exposure – coastal, marine-influenced and sulphate-bearing ground
• Precast concrete elements requiring good early strength and surface finish
• Self-compacting or highly flowable concrete when used in synergy with compatible Fosroc admixtures

Key advantages

• High water-reducing power that lowers the water-cement ratio for greater durability
• Significant improvement in both early (initial) and final compressive strength
• Maintains high workability and pumpability without segregation
• Robust, stable performance – resists large workability swings from minor water additions
• Chloride-free (≤0.10% Cl-), safe for reinforced and prestressed concrete
• Non-flammable liquid, simplifying on-site storage and handling
• EN 934-2 compliant, supporting specification and quality assurance
• Versatile single-product dosing for RMC plus suitability for wet sprayed concrete

Limitations & considerations

• Dosage (0.5-2% by weight of cement) must be established by site trials; overdosing can cause retardation, bleeding or segregation
• Compatibility is limited – among Fosroc superplasticisers it is intended to work with the Euco range; mixing incompatible admixtures can compromise the lowest achievable w/c ratio
• If more than one admixture is used, each must be added separately and never blended together before addition
• Performance varies with cement type, supplementary cementitious materials and aggregate grading, so results are not transferable between mixes
• It is a water reducer/superplasticiser, not an air-entrainer, waterproofer or corrosion inhibitor – those functions require dedicated products
• Shelf life is limited to about 12 months and storage must stay between 2°C and 40°C in sealed original containers
• Liquid admixture requires accurate, calibrated dispensing equipment at the plant for consistent results

Selection & best practice

Specifications

Industry use cases

How we position Fosroc Structuro 352

Fosroc Structuro 352 sits in the high-range water-reducer (superplasticiser) tier of Fosroc’s admixture portfolio, alongside Structuro 351 (a general-purpose superplasticiser for all manufactured concrete), Structuro 311/312 (self-compacting and early-strength variants) and the widely specified Conplast SP430 powder/liquid superplasticiser, which remains the more familiar reference point on many Indian sites. Within that line-up, Structuro 352 is best seen as a robust, single-product choice for RMC plants and wet sprayed concrete where workability stability matters. Against the broader market it competes with Sika’s ViscoCrete range, Master Builders Solutions (MBS) MasterGlenium/MasterRheobuild, BASF-legacy PCE superplasticisers, and the admixture lines from STP and other domestic suppliers; Dr. Fixit (Pidilite) is strong in waterproofing but less dominant in high-range plasticisers, so the more direct head-to-head is with Sika and MBS PCE products. The honest positioning: for projects already standardised on Fosroc systems, or where compatibility with the Fosroc/Euco range and reliable RMC plant performance are priorities, Structuro 352 is a sound specification – but the right admixture for any given mix should always be settled by trial mixes against the specific cement, SCMs and aggregates, regardless of brand. Space Arc Engineering, as an authorised Fosroc distributor, supplies Structuro 352 across Delhi NCR and Pan-India with trial-mix and dosage support.

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