AS 1085.19:2003 pdf – Railway track material Part 19: Resilient fastening assemblies

AS 1085.19:2003 pdf – Railway track material Part 19: Resilient fastening assemblies

AS 1085.19:2003 pdf – Railway track material Part 19: Resilient fastening assemblies.
This Section specifies requirements for resilient clips for use in resilient fastening assemblies.
NOTE: The choice of resilient clip depends on the conditions in which it is to be used. Information supplied in the form of spring rate and fatigue performance will aid in the selection process.
Resilient clips are intended for use to fasten steel rails in place in a track. The resilient clip provides a flexible restraint that holds the rail in position on the sleeper or other supporting structure by providing a spring force of knosn magnitude. They clamp the rail in place in the assembly to facilitate vertical, longitudinal and lateral restraint.
Resilient clips shall be made from steel in accordance with AS 1444 or AS 1447.
Resilient clips shall be provided with a suitable short-term protective coating.
3.5.1 Spring rate and toe load test
The spring rate and design toe load including permanent set after excess deflection of the fastening clip shall be determined in accordance with Appendix H. The toe load (F1) after excess deflection shall not be less than the value specified by the purchaser.
NOTE: The resilient clip design toe load will not necessarily be equivalent to the clamping force determined in Section 2.
3.5.2 Clip fatigue test
The fatigue performance (SN curve) of the resilient clip type shall be determined by testing in accordance with Appendix I.
NOTE: The SN curve resulting from this test can be used in verifying the suitability of a clip for a particular application. Minor variations to clip shape would not necessarily invalidate an SN curve. The SN curve is relevant to the material cross-section and basic geometry.
This Section specifies requirements for rail pads for use in resilient fastening assemblies.
The rail pads are used between the rail and the support structure.
Rail pads provide—
(a) load distribution from the rail to the sleeper. base plate or support structure:
(b) protection of components from abrasion and damage resulting from high localised loading or differential movement;
(c) electrical isolation, if required; and
(d) attenuation of dynamic loads and vibration (usually for concrete sleepers and slabs).
The rail pad shall perform adequately under the assembly tests given in Section 2.
Where the rail pad is required to absorb impact (from dynamic loads), the attenuation performance shall be measured in accordance with Appendix J.
Where required. the rail pad shall provide electrical separation to electrically isolate the rail.