Method of cooling rail weld zone, and rail weld joint

A method of cooling a rail weld zone having a temperature distribution in an axial direction of a rail after welding of the rail has been completed whereby the rail weld zone comprises an Ac1 heated region at a temperature not lower than a starting temperature Ac1 of transformation from pearlite to austenite, and an Ac3 heated region having a temperature not lower than a completion temperature Ac3 of the transformation, the method comprising:

• cooling a rail web portion cooling region of the rail weld zone in a temperature range completing the transformation from austenite to pearlite, in a first rail web portion cooling;
• cooling the rail web portion cooling region in a second rail web portion cooling;
• cooling a foot portion of the rail weld zone in a foot portion cooling;
• and
• cooling a head portion of the rail weld zone in a head portion cooling, wherein, when a cooling time of the first and second rail web portion cooling is t minutes, a k value, obtained by dividing a width L (mm) of the rail web portion cooling region by a width LAc1 (mm) of the Ac1 region, satisfies an expression represented as
• −0.1t+0.63≦k≦−0.1t+2.33.