1. Impact absorption performance (the core indicator determining the safety of sports)
This test simulates the impact force that athletes' joints can withstand.
Testing method: Use a "spring impact hammer" with a pressure sensor installed at the bottom, lift it to a specific height (usually corresponding to the potential energy of human jumping), and then freely fall and smash it onto the floor sample. The sensor will record the peak impact force absorbed by the floor.
Qualification standard: The sports floor should absorb more than 53% of the impact energy (based on EN 14904 standard as a reference). Simple understanding: If the knee joint is subjected to an impact force of 100 kilograms without a floor, it should be reduced to below 47 kilograms with a floor. If the value is too low, the protection is insufficient; if it is too high (such as exceeding 70%), it is like running in a sandpit, and the startup is difficult.
Common failure: The floor support pillar is too high or the material is too soft, causing the impact hammer to directly "touch the bottom" (peak of rigid foundation reaction force), manifested as a secondary peak in the test curve.
2. Vertical deformation performance (determining foot feel softness and energy feedback)
This test measures how much the floor sinks and how quickly it rebounds under stress.
Testing method: Similar to impact absorption testing, but using 3 consecutive impacts (simulating dribbling rhythm), and recording the dynamic sinking scale of the floor surface through laser displacement sensors. Simultaneously calculate the 'rebound rate' - the time required for the floor to return to its original height.
Qualification criteria:
Large vertical deformation: 1.5mm -3.0mm. If it is below 1.5mm, it feels like a cement floor, and if it is above 3.0mm, it is easy to sprain the ankle.
Rebound rate: should be less than 15% (i.e. there should be no significant delay in the rebound time of the floor). Using a ball to land test is more intuitive: the rebound height of a standard basketball from a free fall of 1.8 meters to the floor should be 5% -10% lower than on a concrete floor.
Design correlation: The deformation amount is mainly determined by the aspect ratio of the supporting pillars. The longer the pillar and the thinner the wall thickness, the greater the deformation; The more cross slant support, the smaller the deformation.
3. Sliding performance (dual test of dry and wet state)
The suspended structure itself is hollow, but the surface texture determines its sliding ability.
Dry state test: Use a pendulum friction coefficient tester (similar to a leather friction machine). A standard rubber slider (simulating a sports shoe sole) swings on a dry floor surface, and the dynamic friction coefficient is calculated by the swing angle of the pendulum.
Qualification criteria: Dry dynamic friction coefficient ≥ 1.2 (the rougher the frosted surface, the higher). Attention: It's not necessarily better to have a larger size - stopping abruptly beyond 1.8 can cause the sole to get stuck and increase the risk of knee torsion.
Wet state test: Spray the floor surface until it is completely wet (simulating water accumulation after rain). Repeat the pendulum test mentioned above.
Qualification criteria: Wet friction coefficient ≥ 0.8. The natural growth advantage of suspended structures: water can be easily drained through the grooves at a suitable speed, and the decrease in wet state is usually smaller than that of solid floors.
Special Test: Tilt Platform Method. Fix the floor on an adjustable angle platform, and the tester stands on it wearing standard basketball shoes, gradually raising the angle until it starts sliding. Record the critical angle - the qualification requirement is ≥ 25 ° (dry state) and ≥ 15 ° (wet state).
4. Rolling load and wheel wear (for scenarios such as roller skating and basketball shoes)
Simulate the impact of long-term repeated rolling compaction on floor structure.
Test method: Use a rotating wheel test bench. A steel or polyurethane wheel with a diameter of 75mm and a width of 50mm is subjected to a vertical pressure of 150kg (simulating the weight of an athlete plus impact) and rolled back and forth 20000 times on the floor surface at a speed of approximately 10km/h.
Detection indicators:
Surface wear scale: should be ≤ 0.5mm.
Buckle looseness: Measure the gap between adjacent floors before and after rolling, and the increase should be ≤ 0.3mm.
Whether the supporting pillar is cracked: Use a microscope to check for microcracks at the root of the pillar.
Failure mode: Poor quality flooring will exhibit radial cracks at the intersection of the "m" - shaped reinforcement bars on the surface after testing - due to the concentration of shear stress generated by rolling compaction at this location.
5. Performance degradation after environmental aging (outdoor flooring must be tested)
Simulate the performance retention rate after high-temperature exposure, low-temperature embrittlement, and ultraviolet radiation.
Thermal aging test: Place the floor in a 70 ℃ constant temperature box for 7 days (simulating the temperature of a closed truck or exposed ground in summer), remove and cool for 24 hours, and repeat impact absorption and sliding tests.
Qualification criteria: Performance change rate ≤ 10%. Mainly observe color changes (no obvious yellowing) and whether the lock can open and close normally.
Low temperature impact test: Store the floor at -20 ℃ for 24 hours and immediately test it with an impact hammer (simulating outdoor sports in northern winter). Require that the floor does not exhibit brittle fracture - that is, the fracture surface after impact should be ductile tearing (white brushed), rather than glassy brittle fracture (shiny and flat).
Xenon lamp aging test: Simulate continuous exposure to full spectrum sunlight for 2000 hours. After testing, there should be no powdering on the surface (no white powder when wiped by hand), and the retention rate of tensile strength should be ≥ 80%.
6. Buckle anti pull and anti fatigue (based on actual reports)
Pulling test: After connecting the two floor locks, use a tensile machine to stretch them in opposite directions and record the large force exerted when the locks detach. Qualification standard: ≥ 800N (approximately 80 kg force). Attention: The detachment of the lock buckle should be caused by the deformation of the entire elastic arm before sliding out, rather than a brittle fracture at the root.
Loop opening and closing test: Repeat installation, disassembly, and installation of the same set of locks 500 times. After 500 cycles, the lock buckle should still be able to provide a pulling force of not less than 70% of the initial value. This test exposes whether the material is "stress relaxed" - the elastic arm of low-quality PP material deforms for a long time after multiple uses, resulting in loose fastening.
7. Combustion performance (Enron mandatory item)
Vertical burning test: fix the floor strip vertically, burn it with Bunsen burner (flame temperature is about 1000 ℃) for 10 seconds, and then remove it. requirement:
The flame extinguishes on its own within 30 seconds.
Burning droplets should not ignite the cotton below (to prevent melting droplets from spreading the fire during a fire).
Smoke density test: When the floor is burning without flame, the high smoke density should be ≤ 75% (the lower the value, the better). Suspended structures typically have lower smoke density than solid flooring due to their hollow design.
