Research On Key Technologies About Long-Term Automatic Monitoring Of Under-Rail Settlement In Strong Wind And High Temperature Differential Gobi Region

The second double line in Lanzhou-Xinjiang railway has a design speed faster than200km/h and a total length of1782km. It passes through strong wind areas (the Anxi wind fetch, Yandun wind region, Baili wind region, Dabancheng wind region, the total length of the wind region is580km) and high tempreture differential region. Some sections the line goes through are overflow water damage-prone areas and there are large differences between the engineering geological conditions and hydrogeological conditions. The harsh geographical environment in Xinjiang causes great difficulty in the accurate network control survey and this special geographical situation makes the settlement control of the subgrade, bridge and tunnel of the second double line in Lanzhou-Xinjiang railway become more prominent and difficult. So how to control, monitor and forecast the settlement deformation under-rail effectively is a key technical issue for the construction and safely operation of the second double line in Lanzhou-Xinjiang railway.This article has done field survey and data research, summarized and analyzed existing settlement monitoring methods at home and abroad, learnt from successes and failures of high-speed railway settlement control in operation period all over the world. The under-rail settlement monitoring project which could adapt to the poor weather conditions such as strong wind, extreme heat or cold, high temperature difference in the second double line in Lanzhou-Xinjiang railway was researched and formulated. The new kind high-precision hydraulic settlement gauge which aimed to satisfy the harsh environment conditions in the line and high standards of the settlement in high-speed railway was invented. Field tests were carried out in work sites selected from the line. According to field test and calculation of theoretical analysis and numerical simulation, the settlement law of selected worksite sections was found to verify the high testing accuracy of the hydraulic settlement gauge. Studies have shown that the invented high precision hydraulic settlement gauge would achieve long-term automatic monitoring of under-rail settlement of high-speed railway in strong wind, high high temperature differential Gobi regions and the test accuracy satisfies high-speed railway settlement requirements. This article provides basis for the improvement of under-rail settlement monitoring method in high-speed railway and services for safety operation in the Lanzhou-Xinjiang passenger dedicated line.