Goal
Provide protective guardrail posts that absorb and dissipate kinetic energy from collisions, reducing injuries to pedestrians and vehicle occupants.
Problem
Injuries (lacerations, amputations) caused when a human body impacts the metal support posts of road guardrails.
Concept Summary
A coating made from a mixture of dried Posidonia oceanica (Mediterranean tapeweed) residue and organic or inorganic hydraulic binders, kneaded with water, molded, and cured at room temperature. The resulting composite is applied to guardrail posts, where it absorbs impact energy and reduces transmitted load.
Detailed Description
Researchers at the University of Alicante mixed Posidonia oceanica waste with a hydraulic binder (organic or inorganic) in a 7:1:2 weight ratio (binder:posidonia:water). The dry components are kneaded for ~30 s, water is added and kneading continues for ~2 min. The slurry is poured into a mold, compacted, demolded and cured at ambient temperature for three days. The cured part can be painted with commercial dyes for signaling. The absorber is installed on metal barrier brackets, optionally anchored with a thin PVC sheet. Laboratory tests showed absorption of 4 116 J (impact of a 75 kg body at ~38 km/h) and about 40 % reduction of transmitted load.
Principles
- Impact energy absorption
- Damping
- Composite material formation
- Molding and curing
Scientific Domains
Materials
- Posidonia oceanica residue
- Organic hydraulic binder
- Inorganic hydraulic binder
- Water
- Commercial dyes (optional)
Mechanisms of Action
- Dissipation of kinetic energy through deformation of the composite coating
- Reduction of load transmitted to the underlying metal support
Applications
- Road guardrails
- Safety barriers
- Impact protection for roadside infrastructure
Claimed Performance
Absorbs 4 116 joules of impact energy (equivalent to a 75 kg body at 38 km/h) and reduces transmitted load by about 40 %.
Experimental Evidence
Tests reported in the patent and press release measured impact energy absorption of 4 116 J and a 40 % load-absorption figure under deformation tests.
Replication Status
No independent replication reported; performance data come from the inventors' own tests.
Limitations
- Performance limited to ~40 % load reduction
- Curing time of three days at room temperature
- Requires suitable hydraulic binder selection
- Color additives needed for signaling
