Recycled Rubber Concrete Sub-base Layer for Acoustic and Thermal Insulation

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Solution Overview

Problem

Traditional concrete sub-base layers fail to simultaneously achieve effective thermal insulation and significant reduction in walking impact noise without the need for additional resilient layers, which complicates installation and increases material costs.

Innovation Solution

A lightweight concrete sub-base layer made from pretreated recycled rubber aggregates from discarded tires, with specific composition and treatment processes, including storage in water or washing with latex, to enhance mechanical and acoustic properties, eliminating the need for separate sound insulation layers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If traditional concrete sub-base layers are used, then structural strength is maintained, but thermal insulation is insufficient and walking impact noise is not reduced

Engineering Contradiction:
Improvethermal insulationVSAvoidlayer structure complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent combines thermal insulation function and acoustic insulation function into a single sub-base layer by incorporating recycled rubber aggregates into the concrete mixture. This eliminates the need for separate resilient layers while achieving both thermal and acoustic insulation requirements.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent uses composite materials by mixing traditional concrete components (cement, aggregates, water) with recycled rubber particles from discarded tyres. This creates a multi-functional material that simultaneously provides structural strength, thermal insulation, and acoustic insulation properties.

Inventive Principle:
Principle #40Composite materials

2Object-generated harmful factors

If additional resilient layers are added for sound insulation, then walking impact noise is reduced, but installation complexity and material costs increase

Engineering Contradiction:
Improvewalking impact noiseVSAvoidinstallation complexity
Core Design Contradiction:
Object-generated harmful factorsVSDevice complexity

Solution Approach 1:

The patent merges the acoustic insulation function into the structural sub-base layer itself by using recycled rubber aggregates. This single layer simultaneously provides structural support and reduces walking impact noise, eliminating the need for separate resilient layers and simplifying installation.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The recycled rubber concrete sub-base layer performs multiple functions: it provides structural strength as a load-bearing element, thermal insulation to reduce heat transfer, and acoustic insulation to dampen walking impact noise. This multi-functional material replaces what would traditionally require multiple separate layers.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Temperature

If recycled rubber aggregates are used in concrete, then thermal insulation and acoustic insulation are improved, but mechanical strength is reduced

Engineering Contradiction:
Improvethermal insulationVSAvoidmechanical strength
Core Design Contradiction:
TemperatureVSStrength

Solution Approach 1:

The patent optimizes the parameters of the concrete mixture by controlling the rubber content (10-30% by volume of aggregates), particle size distribution (0-20 mm), and water-cement ratio (0.35-0.45). These parameter adjustments ensure that the sub-base layer achieves the required mechanical strength (compressive strength >1 MPa, flexural strength >0.5 MPa) while maintaining thermal and acoustic insulation properties.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The sub-base layer achieves excellent thermal insulation and a substantial reduction in walking impact noise, meeting regulatory standards without additional resilient layers, while maintaining stability and durability.

Implementation Method 1

concrete with recycled rubber can be used in architectonic applications, road constructions which do not require high resistances, panels that require a low specific weight, building elements and Jersey barriers subject to impact, sound barriers (sound-absorbing)

Methodology Applied
Scientific EffectVibration damping: Damping

Implementation Method 2

The addition of rubber, concrete under load becomes relatively ductile, showing significant deformation capacities before breaking. Furthermore, concretes with rubber particles have lower thermal conductivity coefficients and a higher sound absorption with respect to a traditional concrete.

Methodology Applied
Scientific EffectEnergy absorption: Absorption (physical)

Implementation Method 3

concretes with rubber particles (in substitution of a quantity ranging from 10% to 30% by volume of the aggregate in natural materials) have lower thermal conductivity coefficients and a higher sound absorption with respect to a traditional concrete.

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Data Source

PatentEP3201155B1Lightweight resilient concrete sub-base layer with recycled rubber from discarded tyres with reduced walking impact noise
Publication Date: 2020.10.28 ITALCEMENTI SPA
  • EP3201155B1 patent drawingFigure 1~2
  • EP3201155B1 patent drawingFigure 3a~3c

AI summary

A concrete sub-base layer with pretreated recycled rubber from discarded tyres (PFU), is described.