The train that was travelling from Paris to La Rochelle on the west coast hit the block of concrete at around 10pm on Sunday night near the town of Surgères in the department of Charente-Maritime.
The train was not derailed and although none of the 175 passengers and crew were injured, pictures showed the impact damaged windows of the train.
The train was travelling at between 150 and 200km/h.
The train was delayed by over an hour and other services on the line were also disrupted.
French rail chiefs have pressed charges meaning police will open up an investigation into what has been described as a “malicious act”.
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