The results show that the air and wall temperature rises instantly with high amplitude of temperature variation, when the train moves through the tunnel.

测量结果显示：当隧道内有列车通过时，气温和壁面温度都瞬间升高，气温变化幅度较大。

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With high temperature and quick increase of temperature, the tunnel fire may do a heavy damage to tunnel lining and reduce the reliability of the structural system.

由于隧道火灾温度高，升温速度快，会对衬砌结构造成严重的损坏，并影响衬砌结构体系的可靠性。

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High temperature, coating composition change, expansive agent happen quickly, thus forming porous expansion of insulating layer, prevent heat to the tunnel masonry relay.

高温时，涂料成分发生改变，膨胀剂迅速发生膨胀，从而形成多孔的隔热层，阻止热量向隧道砌体的传递。

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