The basic requirements for the design of the concrete sleepers section according to the use safety are: the probability of the cement railway sleepers section reaching the failure state within the predetermined service life is no greater than the predetermined value. This design concept is not only applicable to the concrete sleeper, but also to the sleeper board, bifurcation pillow and other new underrail foundations, and may be extended to other engineering structures.

The load accepted by the concrete sleepers section on the railway track is "unstable repeated load", so the bearing capacity of the sleeper section refers to the allowable "unstable repeated load" of the sleeper section.

The bearing capacity of concrete sleeper section can be expressed by a "load spectrum curve". According to the test of sleeper section under unstable repeated load, the bearing capacity of sleeper section is greatly related to the maximum load of the section under unstable repeated load, so we can use "maximum load" in the load spectrum curve to represent the entire load spectrum curve.

In the design of the concrete sleeper section according to the safety degree of use, we need to know the average bearing capacity of the sleeper section under the unstable repeated load, which is called the "standard bearing capacity" of the sleeper section. The "standard bearing capacity" of the sleeper section under the unstable repeated load can be obtained through the test of the typical railway sleeper section, and can also be estimated by this calculation method.

In the design of the concrete sleeper section according to the using safety, the "standard bearing capacity" of the sleeper section under the unstable repeated load should be known in addition to the discrete bearing capacity of the section. This can be approximately expressed by the variation coefficient of the static load crack resistance of the sleeper section, known as the variation coefficient of the bearing capacity of the sleeper section.