关键词: 武云高速, 采空区, 残余沉降, 路基稳定性

Abstract: The stability of the old goaf is the key to determine whether the abandoned land resources can be used. Accurate and reliable residual subsidence data is prerequisite for judging the stability of the old goaf. In this paper, the Wuyun expressway construction site is taken as an example, and DS05 level is employed to periodically monitor residual subsidence according to the first order leveling precision requirement. The results show that the accumulated maximum residual subsidence of K30+800~K31+500 is more than 20mm, and its residual subsidence velocity has an obvious characteristic of periodic changes. Residual subsidence of K31+700~K33+000 is smaller than that in K30+800~K31+500, and the accumulated maximum residual subsidence is less than 5mm. Subsidence is also inversely proportional to the depth. The countermeasure for Wuyun expressway construction site is proposed that adding geotextile and geotechnical grille are employed to improve the stability of subgrade. In addition, the flexible material is adopted in pavement to resist the residual subsidence to ensure the security of vehicles running. This work is of general interest to the professional public and it will contribute to a more objective knowledge of residual subsidence for scientific researchers.