为更深层次地探索煤与瓦斯突出机制,在同类突出装置的基础上自主研发了"大型煤与瓦斯突出模拟试验台",其主要由煤与瓦斯突出模具、快速释放机构、承载框架、电流伺服加载系统、翻转机构、主机支架及附属装置组成。分析后认为该试验台具有如下功能:(1)利用电流伺服加载系统可对突出煤样施加均布荷载和阶梯形荷载,模拟工作面前方造成突出的局部应力集中现象。(2)可实现5种不同倾角煤层在不同地应力、不同瓦斯压力下的煤与瓦斯突出模拟试验。(3)利用泡沫不锈钢隔离煤样与进气孔,实现了对突出煤样的"面充气"功能。(4)通过快速释放机构,可瞬间打开突出口使突出端突然卸压。(5)实现了煤与瓦斯突出试验的全过程回放。试验结果表明:有典型的梨形突出孔洞出现,突出的粉煤有明显分选性,且瓦斯压力越大其突出强度越大。所得试验结果与现场突出特征吻合,说明该试验台具有良好的煤与瓦斯突出试验模拟功能。
In order to understand the mechanism of coal and gas outburst, the large-scale test device for coal and gas outburst simulation is developed. The device is composed of outburst assembly, fast-releasing component, load-bearing frame, electric servo-controlled loading system, reversal unit, main frame bracket and accessories. The functions of this test device are analyzed as follows. (1) By using the electric servo-controlled loading system, uniform load and step load on the outburst coal sample can be realized; meanwhile, the outburst phenomenon caused by the concentrated stress in front of the coal face can be simulated. (2) This device can simulate five kinds of coal and gas outburst experiments on coal beds with different obliquities, which are under the different gas pressures and geostresses. (3) The foam-stainless steel is used to separate the coal sample from the air intake on the soleplate of the outburst assembly to realize the plane-charging for the outburst coal sample. (4) By using the fast-releasing component, the outburst ostium can be opened at once and its pressure will become zero. (5) The full process of coal and gas outburst can be monitored by this device. The experimental results indicate that the typical outburst hole appears, the powder coal shows the obvious separation; and the larger the outburst intensity is, the larger the gas pressure is. The experimental results agree well with the in-situ outburst characteristics and indicate that the large-scale coal and gas outburst simulation test device can simulate the outburst of coal and gas effectively.