论文部分内容阅读
青藏铁路高温冻土区的普通路基和保温材料路基均处于热不稳定状态,需要对它们增设碎石护坡-热管复合措施来强化处理,新增设的补强措施对路基下部冻土的保护效果如何是人们极为关心的问题.因此,对北麓河高温高含冰量路段增设了碎石护坡及热管的复合补强措施后路基下部土体的热状态进行观测.结果显示:普通路基在增设补强措施后,人为冻土上限进一步抬升,阴阳坡下均出现显著的降温趋势,且路基下温度场逐渐趋于对称,降温范围逐渐向路基中心及深部发展,路堤中心深部地温仍处于增温状态,但增温趋势明显缓减;保温材料路基在增设补强措施后,人为冻土上限也进一步的抬升至保温板附近,融化夹层在2个冻融周期后消失,路堤中心温度在2个冻融周期后出现了降温趋势.这些效果说明,补强措施在调控路基内部及下部多年冻土温度时发挥了积极作用.
The common embankment and insulation material subgrade in the high temperature permafrost zone of Qinghai-Tibet Railway are all in a thermally unstable state, and they need to be provided with gravel revetment - heat pipe compounding measures to strengthen treatment. The newly added reinforcement measures have the effect of protecting the subterranean permafrost How to deal with the problem that people are most concerned about.Therefore, the thermal state of the soil in the lower part of the subgrade is observed after the gravelly slope protection and the heat pipe are added in the section with high temperature and high ice content in Beiluhe.The results show that the reinforcement of ordinary subgrade After the measures, the artificial upper limit of permafrost was further lifted, significant downward trend appeared in both the yin and yang slopes, and the temperature field gradually became symmetrical under the subgrade. The cooling range gradually developed toward the center and deep of embankment. The deep ground temperature of the embankment center was still warming. However, the warming trend obviously slowed down. After adding reinforcing measures, the upper limit of artificial permafrost increased further to the vicinity of the thermal insulation board. The melting interlayer disappeared after two freeze-thaw cycles and the center temperature of the embankment was between two freeze-thaw cycles After the period, a cooling trend appeared, which indicated that the reinforcement measures played an active role in regulating the temperature of the permafrost in the subgrade and below.