Champaran HumSafar Express : इन अजनबी सी राहों में, जो तू मेरा हमसफ़र हो जाये, बीत जाए पल भर में ये वक़्त, और हसीन सफ़र हो जाये. - Piyush Singh

I think the main reason for adding this portion to the railway tracks is due to "Expansion of Solids" As we know the when the the temprature changes.... like from summers to winters or vice versa... There can be a probability when tracks tend to expand or contract... So this portion provides a sufficient gap between the tracks so that the tracks dont crack or deform from thier orignal shape.... I think this can be a valid reason.... 😊

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