Reasons why rubber asphalt derived from waste tires has not been standardized in Japan are examined from the perspectives of systems, equipment, and evaluation criteria. This analysis focuses on structural conditions rather than performance arguments.
Rubber Asphalt Derived from Waste Tires in Japan
2026-03-08
Premise Organization
Rubber asphalt is an established technology
Implementation examples exist overseas
Limited adoption examples also exist in Japan
It is not a situation where the technology is impossible
There are other reasons why it has not been standardized
Relationship with Existing Technologies
Maturity of Mainstream Pavements
Polymer-modified asphalt
SMA (Stone Mastic Asphalt pavement)
Porous pavement
Long-term track record
Incorporation into specifications
Stable construction framework
No major defects have emerged in existing structures
Strength of Replacement Incentives
Performance insufficiency is not clearly identified
The necessity for substitution is weak
The system is not designed for abrupt changes
Climate and Construction Conditions
Meteorological Environment
High temperature and humidity
Heavy rainfall
Freeze-thaw cycles
Large regional differences
Conditions differ from solutions optimized for dry climates
Construction Stability
Moisture management is important
Risk of quality variability
Market structure emphasizing reproducibility
Facilities and Supply Structure
Plant Compatibility
High-temperature mixing
Swelling time management
Dedicated blending equipment
Compatibility with existing facilities is limited
Investment Rationality
Nationwide standardization requires equipment renewal
The motivation for renewal needs to originate from the institutional side
Evaluation Criteria in Public Procurement
Cost Evaluation
Emphasis on initial cost
Life cycle evaluation is limited
Life extension effects are not strongly reflected in the system
Risk Avoidance Tendency
Emphasis on track record
Structure that avoids deviation from specifications
New technologies tend to be introduced gradually
Current Status of Waste Tire Processing
Processing Routes
Cement fuel
Steel mill fuel
High thermal recycling rate
Urgency
Processing pressure has not become apparent
Policy pressure is weak
Structural Interpretation
Not because performance is inferior
Differences in institutional conditions
Differences in evaluation criteria
Existence of existing facility assets
There is also rationality in not adopting it
Rubber pavement can be positioned as an institutional structural issue rather than a material issue