What Is Ready Mix Concrete and Its Key Types

What Is Ready Mix Concrete and Its Types?

Table of Contents

Ready mix concrete is pre-batched at a central plant according to precise specifications. It is delivered to construction sites fresh and workable, ready for immediate placement. This factory-controlled process ensures consistent quality, accurate mix proportions, and reliable strength for every load.

The main types include transit-mixed, central-mixed, and shrink-mixed concrete. There are also performance variants such as standard, high-strength, fibre-reinforced, self-compacting, and rapid-setting mixes. Knowing the different types of ready mix concrete helps contractors, builders, and homeowners choose the right product for their project, whether it’s a garden path or a multi-storey building.

What Is Ready-Mix Concrete?

Ready-mix concrete represents a fundamental shift from traditional on-site mixing methods. Instead of combining raw materials at the construction location, this approach centralises production at specialised batching facilities where every aspect of the mix can be monitored and controlled.

Definition of Ready-Mix Concrete

Ready-mix concrete refers to concrete manufactured in a factory or batching plant according to a set recipe and then delivered to the job site by truck in a plastic, unhardened state.

The concrete arrives ready for placement without any additional mixing or preparation required on-site. This definition distinguishes it from site-mixed concrete, where raw materials are combined manually or mechanically at the construction location.

How Ready-Mix Differs from Site-Mixed Concrete

The differences between ready-mix and site mixed concrete extend far beyond simple convenience.

Factor	Ready-Mix Concrete	Site-Mixed Concrete
Quality Control	Factory-controlled, consistent	Variable, operator-dependent
Mix Accuracy	Computer-batched precision	Manual measurement
Labour Required	Minimal on-site mixing labour	Significant mixing of labour
Equipment Needed	Delivery truck only	Mixers, storage, measuring
Material Wastage	Low (precise quantities)	Higher (over-ordering common)
Speed	Fast placement	Slower batch-by-batch

Did you know?

Site-mixed concrete can vary by up to 15% in strength from batch to batch, while factory-batched ready-mix typically maintains consistency within 5% of target strength.

Basic Ingredients and Mix Design (Cement, Aggregates, Water, Admixtures)

Every concrete mix consists of four primary components combined in specific proportions to achieve desired performance characteristics.

Core ingredients include:

Cement: The binding agent that reacts with water to form the hardite paste holding everything together
Fine Aggregates: Sand particles that fill gaps between larger stones
Coarse Aggregates: Gravel or crushed stone providing bulk and strength
Water: Initiates the chemical reaction and affects workability
Admixtures: Chemical additives modifying specific properties like setting time, workability, or durability

Pro Tip:

The water-to-cement ratio is the single most important factor affecting concrete strength. Lower ratios produce stronger concrete but reduce workability, so admixtures often compensate to maintain both properties.

How Ready-Mix Concrete Is Produced and Delivered

The production and delivery process involves carefully orchestrated steps, ensuring concrete arrives at your site in optimal condition for placement.

Central Batching Plant and Quality Control

Modern batching plants use computerised systems to measure and combine materials with exceptional precision.

Quality control measures include:

Automated weighing systems are accurate to within 1% of target quantities
Moisture sensors adjust water content based on aggregate conditions
Regular testing of raw materials for compliance with standards
Slump testing and cube sampling for strength verification
Temperature monitoring during hot or cold weather

These plants can produce hundreds of cubic metres daily while maintaining consistent quality across every batch.

Mixing, Loading, and Transport in Truck Mixers

Once batched, concrete transfers to specially designed truck mixers for delivery to construction sites.

The transport process involves:

Loading freshly batched concrete into the truck’s rotating drum
Continuous agitation during transit to prevent segregation
Maintaining the drum rotation speed appropriate for the journey length
Adding water on-site if needed (within specified limits)
Documenting delivery time to ensure placement within the workability window

On-Site Handling, Placement, and Workability Time (Slump, Setting)

The clock starts ticking once concrete leaves the plant, making efficient site preparation essential.

Stage	Typical Time Frame	Key Considerations
Transport	30-90 minutes	Distance, traffic, weather
Workability Window	60-90 minutes	Temperature, admixtures used
Initial Set	30-45 minutes after placement	No further working possible
Final Set	6-10 hours	Light foot traffic may be possible
Full Cure	28 days	Full design strength achieved

Main Types of Ready-Mix Concrete by Mixing Method

The method used to mix concrete significantly affects its properties upon arrival at your site. Three primary approaches exist, each suited to different project requirements and delivery distances.

Transit-Mixed (Dry-Batched) Concrete

Transit-mixed concrete involves loading dry or partially mixed materials into the truck mixer at the plant, with mixing occurring during transport.

Characteristics of transit-mixed concrete:

Materials are batched dry or with minimal water at the plant
Full mixing happens in the truck drum during delivery
Allows longer transport distances before workability loss
Driver controls final water addition on site
The most common method in the UK

This approach offers flexibility because the mixing process can be timed to arrive at optimal consistency regardless of traffic delays.

Central-Mixed Concrete

Central-mixed concrete undergoes complete mixing at the batching plant before loading into the truck for delivery.

Key features include:

Thorough mixing in stationary plant mixers
Higher initial consistency and uniformity
The truck drum is used only for agitation during transport
Better suited for shorter delivery distances
Often specified for high-performance applications

The more thorough mixing at the plant typically produces slightly more consistent results than transit mixing.

Shrink-Mixed Concrete

Shrink-mixed concrete represents a hybrid approach combining elements of both central and transit mixing methods.

The shrink-mix process involves:

Partial mixing at the plant (approximately 70% complete)
Final mixing completed in the truck during transport
Reduces drum wear compared to full transit mixing
Maintains good quality control from plant mixing
Offers a balance between consistency and transport flexibility

When to Choose Each Mixing Method for Projects

Selecting the appropriate mixing method depends on your project’s specific circumstances.

Mixing Method	Best For	Distance	Quality Priority
Transit-Mixed	Standard projects, longer hauls	Up to 90 minutes	Good
Central-Mixed	Critical applications, short distances	Under 30 minutes	Excellent
Shrink-Mixed	Medium distances, balanced needs	30-60 minutes	Very Good

Pro Tip:

For projects requiring C35 concrete or higher-strength mixes, central-mixed or shrink-mixed methods often produce more consistent results due to the controlled plant environment.

Types of Ready-Mix Concrete by Performance and Application

Beyond mixing methods, ready-mix concrete comes in numerous performance variants designed for specific applications and conditions.

Standard / Ordinary Ready-Mix Concrete

Standard ready-mix serves the majority of construction applications where no special performance requirements exist.

Common applications include:

House foundations and footings
Garage floors and shed bases
Garden walls and pathways
General structural elements
Domestic extensions

This versatile option covers grades from C10 through C25, suitable for most residential and light commercial work.

High-Strength Ready-Mix Concrete

High-strength mixes exceed 40 N/mm² compressive strength, enabling the construction of demanding structural elements.

Typical uses for high-strength mixes:

Multi-storey building frames
Bridge decks and supports
Precast concrete elements
Industrial flooring subject to heavy loads
Marine and infrastructure projects

Did you know?

Ultra-high-performance concrete can achieve compressive strengths exceeding 150 N/mm², nearly ten times stronger than standard domestic mixes.

Fibre-Reinforced Ready-Mix Concrete

Fibre-reinforced concrete incorporates steel, glass, synthetic, or natural fibres throughout the mix to enhance specific properties.

Benefits of fibre reinforcement:

Improved crack resistance and control
Enhanced impact and fatigue resistance
Reduced plastic shrinkage cracking
Potential replacement for traditional mesh reinforcement
Better durability in aggressive environments

This type proves particularly valuable for industrial floors, pavements, and shotcrete applications.

Self-Compacting / Self-Consolidating Concrete (SCC)

Self-compacting concrete flows and consolidates under its own weight without requiring mechanical vibration.

Advantages of SCC include:

Eliminates vibration noise and equipment needs
Fills complex formwork and congested reinforcement
Produces superior surface finishes
Reduces labour requirements
Speeds up placement in difficult access areas

Lightweight and High-Density Ready-Mix Concrete

Adjusting aggregate types produces concrete with significantly different densities for specialised applications.

Type	Typical Density	Applications
Lightweight	1,400-1,800 kg/m³	Upper floors, roof decks, thermal insulation
Normal	2,300-2,400 kg/m³	Standard construction
High-Density	2,600-6,000 kg/m³	Radiation shielding, ballast, counterweights

Lightweight variants use expanded clay, shale, or pumice aggregates, while high-density mixes incorporate materials like barytes or magnetite.

Rapid-Setting and Early-Strength Ready-Mix Concrete

When project timelines demand fast turnaround, rapid-setting mixes achieve working strength in hours rather than days.

Applications for rapid-setting concrete:

Road repairs requiring quick reopening
Cold weather concreting
Precast production efficiency
Emergency repairs
Fast-track construction schedules

Speciality and Custom-Designed Ready-Mix Mixes

Modern batching technology enables the creation of bespoke mixes tailored to unique project requirements.

Speciality options include:

Coloured concrete for decorative applications
Exposed aggregate finishes
Waterproof and watertight mixes
Chemical-resistant formulations
Low-heat mixes for mass concrete pours
Sulphate-resistant concrete for aggressive ground conditions

Ready-Mix Concrete Grades and Common Uses

Concrete grades indicate the characteristic compressive strength achieved after 28 days of curing, providing a standardised system for specifying requirements.

Overview of Ready-Mix Grades (e.g., M10–M60 and Above)

The grading system uses letters and numbers to denote strength class and specific properties.

Grade Range	Strength (N/mm²)	Category
C10-C15	10-15	Ordinary/Gen
C20-C25	20-25	Standard
C30-C35	30-35	Standard to High
C40-C50	40-50	High Strength
C55-C60+	55-60+	Very High Strength

Ordinary Grades for Non-Structural and General Use

Lower-grade mixes serve applications where structural loading remains minimal.

C10 and C15 uses:

Blinding layers beneath foundations
Drainage and trench fill
Mass concrete applications
Kerbing and edging
Agricultural flooring
Cavity filling and backfill

These economical options provide adequate performance without over-specifying for simple applications.

Standard Grades for Residential and Commercial Structures

Mid-range grades form the backbone of most construction projects.

C20 through C30 applications:

Domestic foundations and footings
Floor slabs and suspended floors
Retaining walls
Paving and driveways
Reinforced structural elements
Commercial building frames

C35 concrete represents a popular choice for projects requiring enhanced strength without speciality mix requirements, offering excellent durability for demanding applications.

High-Strength Grades for Bridges, High-Rise, and Heavy-Duty Work

Projects involving significant structural loads or challenging conditions demand premium-grade concrete.

C40 and above applications:

High-rise building columns and cores
Bridge decks, piers, and abutments
Industrial heavy-duty floors
Precast structural elements
Water-retaining structures
Marine and coastal construction

For critical infrastructure projects, these high-performance mixes deliver the strength and durability essential for long service life.

Advantages of Using Ready-Mix Concrete

The widespread adoption of ready-mix concrete reflects numerous benefits over traditional site-mixing approaches.

Consistent Quality and Strength

Factory production eliminates the variability inherent in manual mixing processes.

Quality advantages include:

Computer-controlled batching ensures precise proportions every time
Regular testing verifies material properties and mix performance
Qualified technicians oversee production processes
Documented quality records provide traceability
Consistent slump and workability characteristics

Time Savings and Faster Construction

Ready-mix dramatically accelerates construction schedules compared to site mixing.

Time benefits include:

No waiting for materials to be mixed on site
Larger volumes are placed in shorter periods
Continuous pours are possible for critical elements
Reduced overall project duration
Faster progression between construction phases

Reduced On-Site Labour and Wastage

Centralised production transfers much of the work away from the construction site.

Labour and wastage benefits:

No mixing crew required on site
Eliminated storage areas for cement, aggregates, and sand
Reduced material handling and spillage
Precise ordering minimises over-supply waste
Cleaner, more organised job sites

Environmental and Sustainability Benefits

Ready-mix production offers environmental advantages over traditional methods.

Sustainability factors:

Efficient material usage reduces resource consumption
Dust and noise are contained within plant facilities
Recycled aggregates more easily incorporated
Returned concrete can be reclaimed and processed
Lower overall carbon footprint per cubic metre

Did you know? Modern batching plants can reclaim wash water and return concrete, with aggregates recycled into new mixes and water reused in production.

How to Choose the Right Type of Ready-Mix Concrete

Selecting appropriate concrete involves matching technical requirements with practical project constraints.

Matching Mix Type to Structural Requirements

Different structural applications demand specific performance characteristics.

Structural matching considerations:

Load-bearing capacity determines the minimum strength grade
Reinforcement requirements influence workability needs
Element thickness affects aggregate size limits
Finishing requirements guide consistency specifications
Curing conditions may dictate special admixtures

Pro Tip: Always consult your structural engineer’s specifications before ordering. Under-specifying risks structural failure, while over-specifying wastes resources unnecessarily.

Considering Exposure, Durability, and Local Standards

Environmental conditions significantly influence appropriate mix selection.

Exposure Class	Conditions	Mix Requirements
XC1	Dry or permanently wet	Standard mixes suitable
XC3/XC4	Moderate humidity, wetting/drying	Enhanced cement content
XD	De-icing salts	Chloride-resistant mixes
XS	Marine	Sulphate-resistant cement
XF	Freeze-thaw	Air-entrained mixes

Durability factors to consider:

Ground conditions and sulphate levels
Freeze-thaw cycle frequency
Chemical exposure risks
Abrasion and wear patterns
Required service life

Working with Your Concrete Supplier for Custom Mixes

Experienced suppliers provide valuable guidance for complex projects.

Supplier collaboration benefits:

Technical expertise in mix design optimisation
Knowledge of local aggregate properties
Understanding of admixture performance
Experience with similar project types
Access to testing and quality documentation

For projects requiring pumped placement, Concrete Pump Hire services combined with appropriately designed mixes ensure efficient delivery to difficult access areas.

Conclusion

Ready mix concrete has changed construction by providing factory-controlled quality, consistent strength, and efficient placement directly to job sites. Its versatility suits everything from domestic foundations to high-performance structural elements. Different mixing methods, performance variants, and grades ensure there’s a suitable product for nearly every construction need.

For projects across London and the surrounding areas, Pro-Mix Concrete delivers reliable ready mix concrete with over 20 years of experience. Their services include Ready Mix Concrete, Mix On Site Concrete, and Concrete Pump Hire, supporting domestic extensions and large commercial developments alike. Same-day and next-day delivery, computer-controlled batching, and a team of certified experts ensure each pour meets exact project requirements. Their concrete grades range from C10 for general use to C35 and higher-strength options for demanding structural applications.

Frequently Asked Questions

What is ready-mix concrete?

Ready-mix concrete is factory-batched concrete made to a specified mix design at a central plant and delivered to the job site in a truck ready to place. This approach ensures consistent quality, precise proportions, and reliable strength compared to traditional site-mixing methods.

What are the main types of ready-mix concrete?

The main types are transit-mixed, central-mixed, and shrink-mixed concrete, with additional variants such as standard, high-strength, lightweight, fibre-reinforced, self-compacting, and rapid-setting mixes. Each type serves specific applications and performance requirements.

How do I choose the right type of ready-mix concrete for my project?

Choose a ready-mix type based on the structural load, exposure conditions, required strength, placement method, and your engineer’s or supplier’s recommendations for that specific application. Consulting with experienced suppliers helps ensure appropriate specifications.

Is ready-mix concrete better than site-mixed concrete?

Ready-mix concrete is generally better for most projects because it offers more consistent quality, stronger control over mix design, less on-site labour, and faster placement than site-mixed concrete. However, site mixing may suit very small quantities or remote locations.

Can ready-mix concrete be customised for different uses?

Yes, ready-mix concrete can be customised by adjusting the cement content, aggregate grading, water content, and admixtures to create mixes tailored for uses like high-strength structural work, slabs, floors, or fast-track repairs. Modern batching technology enables virtually unlimited customisation possibilities.