SpikeFast Performance Tests
Performance tests commissioned by national railroads indicate that SpikeFast outperforms wood plugs, polymeric foam and epoxy foam in both lateral resistance and pullout resistance. The test results show that SpikeFast is the leading spike-hole filler in the railroad industry. SpikeFast had high marks in tests such as spike insertion and withdrawal, where results indicated that SpikeFast's withdrawal force is equivalent to that of unspiked hardwood ties and nearly twice that of wood plugs and foam. SpikeFast also had high results in the lateral resistance testing, where SpikeFast shows the resistance was 20% higher than that of previously unspiked hardwood ties.
See below for performance tests and their results on SpikeFast.
DESIGN CONCEPT AND CRITERIA
The existing spike-hole plugging products on the market consist of wooden plugs and a rigid foam product. These products attempt to repair the tie holes using properties similar to wood (i.e., similar compressive strength).
Rather than mimic this approach, our Railroad Division developed and engineered a new solution. A new design concept that ultimately led to the development of SpikeFast, involved filling the spike hole with a material having similar properties to the metal spike (i.e., compressive strength much higher than wood). In other words, rather than employ a wood repair, conceptually use a bigger spike.
The design objectives are:
1. Typical spike insertion force must be less than or equal to 11,000 lbs. The basis for the maximum insertion force is the force required to spike virgin white oak.
2. Typical spike withdrawal force must be greater than 6,000 lbs., which is significantly greater than wood plugs.
3. Performance must be maintained during all weather conditions including heavy rain, freezing temperatures and high humidity.
REACTION WITH WATER
SpikeFast does not react with water. Unlike the foam filler alternatives, SpikeFast retains its easy application and superior performance characteristics during all weather conditions including heavy rain, freezing temperatures and high humidity.
SPIKE INSERTION AND WITHDRAWAL FORCE
Results indicate that SpikeFast's spike withdrawal force is equivalent to that of unspiked hardwood ties and nearly twice that of wood plugs and foam – meaning you keep gauge longer. SpikeFast is as hard as red oak ties. When inserting the spike into a wood tie, SpikeFast allows the wood fibers to compress around the spike, thus providing superior holding properties.
In a separate study, spike holes filled with the SpikeFast required an average of 1000 lbs., additional force to drive the cut spike into the material. To measure the withdrawal force, the cut spikes were pressed in and pulled out using a large tensile/compression machine.
This test indicates that SpikeFast has incredible spike holding properties – yet another reason why SpikeFast is the plugging material of choice for five of the six Class A railroads.
LATERAL RESISTANCE TESTING
The AAR (Association of American Railroads) commissioned a comprehensive evaluation of all commercially available tie-plugging materials, including wood plugs, polymeric foams, and SpikeFast.
The lateral test results were obtained by measuring the force needed to laterally deflect a cut spike head 0.2 inches, which simulates rail-gauge loss (i.e., widening between the rails).
Due to using actual 20-year-old ties with wallowed-out spike holes and a wide range of tie integrity, a correspondingly wide range of analytical results were obtained. Therefore, all tests were conducted 20 to ~50 times and the results were averaged.
The data indicates that SpikeFast's lateral resistance was 20% higher than that of previously unspiked hardwood ties. These results indicate why it's beneficial to use SpikeFast over other plugging materials to minimize rail gauge loss.
DYNAMIC RAIL ROLLOVER TESTING
The results of a dynamic rail rollover study by a Class 1 railroad indicate that SpikeFast's resistance to rail rollover outperforms wood plugs two to one and can be compared to virgin oak.
Three million 32,000 lb. loading cycles at 3 Hertz were applied vertically against a railhead (two-feet long piece of rail) to simulate wear typically encountered in the field. Simulated spike holes (3/4" with grain X 1" against grain X 5" deep) were pre-drilled into a virgin tie and filled with candidate-plugging materials. The railhead was anchored to a virgin tie with a single rail plate using four cut spikes.
After the loading cycles were completed, the lateral force needed to roll the rail over was measured. Each measurement was performed once.
SpikeFast DEFLECTION TESTING - PRELIMINARY
Preliminary test results indicate that SpikeFast significantly outperforms virgin oak and wood plugs, thus allowing track repairs to happen less frequently than with other plugging materials. SpikeFast will continue to be tested until a deflection of 1/2" is obtained.
The test used standard cut spikes and standard virgin oak ties with simulated spike holes (3/4" with grain X 1" against grain X 5" deep). A single spike was inserted into a spike hole filled with various plugging materials. A 2000 lb. lateral force was cycled against the spike head. The number of loading cycles to laterally deflect the spike 0.5 inches was then used to compare the performance of candidate spike-hole filler materials.
The spike broke with the tests using an oak plug and a virgin oak tie, at the point indicated on the graph. It is speculated that the spikes broke due to loosening of the hole. Additional tests are planned to repeat these tests. SpikeFast's test results show that SpikeFast offers superior performance compared to other spikehole fillers.
RETURN ON INVESTMENT
Rail maintenance and refurbishment performed with SpikeFast lasts longer than with the alternatives. The fact that five out of the six class 1 railroads uses SpikeFast, is a testament to SpikeFast's success in the railroad industry.
A simple ROI model, based on dynamic laboratory test results, indicates that tie refurbishment using SpikeFast enables maintenance crews to revisit the same track for re-gauging operations less often, allowing their resources to be reallocated for greater efficiency.
Further, the ROI is much higher than this simple model indicates because tighter gauge means not only less overall wear to the ties, but also to the railhead and spike collars.
Injuries from gauging operations, and the safety repercussions of losing gauge, is perhaps the most difficult to measure but is also a critical factor.