High-temperature mechanical property testing system of annular tunnel lining structure system

Abstract

The invention discloses a high-temperature mechanical properties testing system of lining structure system of circular tunnel, which includes the following seven parts: fire thermal environment simulation subsystem; heat insulation subsystem; base and lining structure mechanical border simulation subsystem; loading subsystem, measurement subsystem; data acquisition subsystem; lining structure thermal border simulation subsystem. This tested system can better simulate characteristics of the tunnel fire (quick heating-up, high maximum temperature reached) and a variety of tunnel fire scenes; can simulate the thermal border condition of tunnel lining structure system and effect of surrounding soil, groundwater to components; can simulate the effect of formation resistance force to lining structure system; can impose a variety of loads- temperature conditions to lining structure system; can impose different displacement border conditions to lining structure system. The invention is safe, reliable, easy to use, with low failure rate, can meet the requirements of mechanical performance test of tunnel lining structure at high temperature (after high temperature).

Description

technical field [0001] The invention relates to a test device, in particular to a device for performing a high-temperature mechanical performance test on a circular tunnel lining structure system. Background technique [0002] Fire will reduce the mechanical properties of concrete and steel bars in the tunnel lining structure system, reduce the bearing capacity of the lining structure system, and may cause the collapse of the tunnel lining structure system. Especially for prefabricated lining structure systems, such as shield tunnels, immersed tube tunnels, etc., it will also lead to a decrease in the performance of weak parts such as joints, causing water leakage or even damage to the tunnel. At the same time, the tunnel lining structure system is different from the ground structures. The permanent deformation caused by the fire will not only lead to the redistribution of the internal force of the structure system, resulting in the reduction of the bearing capacity of the s...

AI Technical Summary

Problems solved by technology

[0012] Preface No heating method temperature control method shortcoming 1 electric furnace heating Temperature Controller The heating rate is slow, about 10-20°C / min; it cannot reflect Characteristics of tunnel fires 2 Gas heating up By manually adjusting the fuel (gas, fuel oil) to control the furnace temperature to make it follow the predetermined temperature rise curve Variety (1) There is no automatic control equipment, and it is not easy to control the temperature manually Increase according to the set curve (2) The maximum temperature that can be reached is low, which cannot reflect the tunnel The characteristics of high fire temperature 3 oil heating The combustion bed is welded with steel plates, according to the fire A certain amount of fuel (firewood oil+gasoline); by adjusting the ventilation volume control burn rate (1) It is not easy to control the temperature to rise according to the set curve; (2) It is difficult to carry out automatic control (3) Not safe enough; a large amount of dense smoke, polluting the environment 4 Refractory brickwork coke burning Burn test furnace (1) Combustion is controlled by the amount of coke the peak temperature in the process; (2) By adjusting the air intake to control heating rate (1) The heating rate is slow (2) It is not easy to control the temperature to rise according to the set curve

[0013] Judging from the heating methods used by these test devices, the main problems are that the heating speed is slow, or the maximum temperature reached is low, or the temperature cannot be accurately controlled to rise according to the predetermined heating curve, which cannot reflect the tunnel fire well. specialty

Secondly, in simulating the thermal boundary conditions of the tunnel lining structure, these devices hardly consider the influence of the surrounding rock and soil on the high temperature mechanical properties of the lining structure system

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