Fibre-reinforced concrete shows up everywhere now — steel fibres in industrial slabs replacing mesh, macro-synthetic in tunnel lining, micro-fibre in residential for shrinkage control. Pumping it is standard, not specialist — but fibres change rheology and wear, and pretending it's plain 25 MPa is how you block a line and chew through a wear plate in one pour.
Fibre types and pump behaviour
- Steel fibres — hook-end, flat sheet, collated bundles. Increase friction, align in flow direction in the line, accelerate wear on elbows and S-tube components.
- Macro-synthetic — thicker plastic fibres for structural substitution in some applications. Springy, can bridge at tight bends if mix is dry.
- Micro-synthetic — less impact on pumpability, still notify operator — batch consistency matters.
Mix design for pumpable fibre concrete
Successful pumped fibre mixes usually carry higher paste content, careful aggregate top size (often 20mm max, frequently 14mm), and slump/workability tailored with admixtures rather than water. Fibre dose per spec — overdosing looks good on paper, pumps terribly.
Share fibre type, dose, and mix ticket with MetroFlow at booking — we adjust rate expectations and inspect wear-sensitive gear afterward on heavy jobs.
Operator adjustments
- Slightly lower peak output on high steel dose — continuous flow over hero pressure.
- Minimise 90° bends in line work.
- Monitor wear indicators — maintenance cycles shorten on fibre-heavy programs.
- Avoid long idle with fibre mix in line — stiffening plus fibre matting is miserable.
Applications across Victoria
Warehouse floors in the west, carpark slabs, shotcrete-style tunnel repair with steel fibre, residential slabs where engineer specifies fibre instead of mesh. Often overlaps flatness-critical pours — steady feed still rules.
Common mistakes
- Ordering standard slab mix and adding fibres at plant without pumpability redesign.
- Using line reducers too aggressive for fibre length — fibres catch at step-downs.
- Assuming boom reach fixes a harsh fibre mix — geometry doesn't change rheology.
Wear and cost honesty
Fibre pours may carry slightly higher pump pricing when dose and volume justify accelerated wear and slower rate — we quote transparently, not via surprise invoice line items. Cheaper to price honestly than replace pump end mid-contract.
Fibre concrete is the future of a lot of slab work — pumped daily by operators who respect what fibres do in a bend.
Steel fibre warehouse programs
Multi-day warehouse programs with steel fibre wear pump ends faster — we schedule wear inspection between days on large pours. Fibre dose and output cap agreed upfront prevents mid-contract dispute about whether mix or maintenance caused slowdown.
Synthetic macro fibre residential
Residential slabs replacing mesh with macro synthetic need pump-friendly mix design — fibre length must pass bends in route. Tell us side access length when quoting; long runs plus long fibre is a design conversation, not pour-day improvisation.
Handling at hose end
Fibre exposure at hose end can irritate skin — PPE for finishers handling wet fibre mix standard on steel fibre industrial pours. Pump operator warns crew on first load when steel fibre dose high; safety briefing item, not afterthought.
Finishers sometimes report fibre balling at surface — often mix design or over-finishing issue, but pump surging contributes. Steady feed supports uniform fibre orientation specifiers expect in structural submission.
Frequently asked questions
- Steel fibre vs mesh — pump difference? Fibre increases wear and friction — mix design adjusted accordingly.
- Can residential slabs use fibre? Yes — growing specification; tell pump company fibre type and dose.
- Extra cost? Possibly for wear and rate — quoted transparently.
- Macro synthetic pumpable? Yes with correct mix and bend planning — confirm at quote.
Specification changes mid-project from mesh to steel fibre should trigger batch plant and pump company notification before first fibre pour — retrofits without pumpability review cause first-day blocks that poison confidence in the whole specification change.
Industrial clients auditing fibre dosage sometimes correlate pump wear invoices with volume pumped — transparent maintenance reporting supports fibre specification value proposition against mesh alternatives in tender submissions.
First fibre pour on a program includes brief stand-down after twenty cubes to inspect hose wear points — precaution cheaper than blowout on hour three.
Booking with MetroFlow
Every pour starts with the same information: address or site, estimated volume, mix details if known, and photos of access from street to pour point. We respond with pump type recommendation, boom class if applicable, and all-in pricing without hidden wash or travel surprises on standard Metro jobs. On program work across Victoria, we hold rates and assign consistent operators where repeat quality matters. Whether your job is a Narre Warren house slab, a Geelong warehouse bay, or a Richmond basement wall, the physics of pumping don't change — only the geometry and mix do. Send the details through our quote form or call direct; we'd rather talk you out of the wrong pump than sell you the expensive one. Good pours are boring pours — preparation, honest communication, and operators who've seen your problem before make pour day forgettable in the best way.
Fibre spec on your drawings? Send mix design — we'll confirm pumpability and quote rate expectations honestly.