The three main reasons for failure of asphalt pavement are plastic deformation, thermal cracking and fatigue cracking. In Canada temperatures on the surface of the asphalt pavement can cover a range of 100 degrees Celsius over the course of a year. Extremely high temperatures can cause the asphalt pavement to become very soft.

In this case, the deep indents were caused by a vehicle being parked on the soft pavement for an extended period of time.

Heavy traffic using the roadway could make ruts in the soft pavement surface.

When the temperature becomes very cold, the asphalt pavement could become so brittle that thermal cracks appear in the surface (usually across the roadway).

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The slump of the asphalt in this case could be due to several problems which the civil engineer must address: there could be a problem with water running under the road; during construction the substructure may not have been compacted adequately;

or the type of traffic using the road may be heavier than was originally expected.

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Constant usage by large, very heavy vehicles will eventually cause fatigue cracking (usually along the length of the roadway). Many rural roads were built using an asphalt emulsion where the asphalt was sprayed on a prepared bed of gravel. They were built very inexpensively this way. This was fine when the road was only used by a few small farm vehicles but with increasing usage by heavy machinery and big trucks, many of the paved roads are slowly going back to gravel.

With proper maintenance the average life of an asphalt paved road is about fifteen years.