Abstract To understand the fire resistance of steel-concrete-steel composite structure and further provide the ba? sis for its structural design and fire protection, the multifunctional large refractory-lined test furnace which is independently developed was used for the fire resistance test of local full-sized elements in different fire protection schemes to research the law of heat transfer of the tube structure of steel-concrete-steel immersed tube tunnel at high temperature caused by a fire. The results show that fireproof plates can greatly protect the tube structure in a fire, and if no fireproof plates are used for protection, obvious voids in concrete will appear in the vertical position of elements; the temperature value at each measuring point on the unexposed surface of a fireproof plate regularly varies with the hearth temperatures, but they do not completely synchronize, and the temperature changes in the measuring point on the unexposed surface of a fireproof plate lag behind those of the hearth; the depth of temperature influence on the tube structure at high temperature caused by a fire reaches about 550 mm from the upper surface of bottom plate, and the height of heat transfer of the concrete section is about 400 mm.
Abstract：
To understand the fire resistance of steel-concrete-steel composite structure and further provide the ba? sis for its structural design and fire protection, the multifunctional large refractory-lined test furnace which is independently developed was used for the fire resistance test of local full-sized elements in different fire protection schemes to research the law of heat transfer of the tube structure of steel-concrete-steel immersed tube tunnel at high temperature caused by a fire. The results show that fireproof plates can greatly protect the tube structure in a fire, and if no fireproof plates are used for protection, obvious voids in concrete will appear in the vertical position of elements; the temperature value at each measuring point on the unexposed surface of a fireproof plate regularly varies with the hearth temperatures, but they do not completely synchronize, and the temperature changes in the measuring point on the unexposed surface of a fireproof plate lag behind those of the hearth; the depth of temperature influence on the tube structure at high temperature caused by a fire reaches about 550 mm from the upper surface of bottom plate, and the height of heat transfer of the concrete section is about 400 mm.
JIANG Shuping1,
2 LI Jing1 ZHANG Dandan1 CAO Peng2
.Experimental Study on the Law of Heat Transfer of Tube Structure of the Steel-concrete-steel Immersed Tube Tunnel[J] MODERN TUNNELLING TECHNOLOGY, 2023,V60(1): 168-178
2023, Vol. 60 