郑家湾滑坡体蠕变对上跨桥梁的影响分析

IMPACT ANALYSIS OF CREEP MOVEMENT OF ZHENGJIAWAN LANDSLIDE TO BRIDGE ACROSS

当前滑坡蠕变对上跨桥梁影响研究甚少,实测数据更为匮乏。在对郑家湾滑坡体及上跨桥梁进行长期监测的基础上,根据深部位移监测数据推断出滑坡潜在滑面位置,分析了气象因素对滑坡及桥梁变形的影响,进而研究了滑坡蠕变与桥梁变形的相关性。研究表明:(1)郑家湾滑坡深约3~19m,月位移0.64~5.16mm,累积位移20~62mm,处于间歇性蠕滑状态。(2)降雨控制着郑家湾滑坡蠕变与桥梁变形,监测期间月最大降雨量390.2mm,此时滑坡与桥梁变形幅度最大,分别为2mm·月^(-1)和7mm·月^(-1)。(3)桥梁变形与滑坡蠕变具有同步性,两者月位移相差0.24~2.13mm,累积位移相差6.3mm。本文数据和结论对郑家湾滑坡治理及今后类似上跨桥梁滑坡的分析具有很好的借鉴意义。

Current research of the impact of landslide creep on bridge across the landslide is far from consummate.Measured data is deficient as well. On the basis of long-term monitoring of Zhengjiawan landslide and the bridge across it,the potential sliding surfaces of landslide are inferred according to monitoring data of deep displacement.The influence of meteorological factors on the monitoring data is analyzed. Moreover,the correlation between the creep of landslide and bridge deformation is studied. Study results show as follows.（ 1） Depth of Zhenjiawan landslide is 3 - 19 m,and monthly displacement is 0. 64 - 5. 16 mm,and the cumulative displacement is 20 - 62 mm,which proves that the landslide is creeping intermittently.（ 2） The deformation of Zhengjiawan landslide and bridge is dominated by rainfall. During the monitoring period the maximum monthly rainfall is 390. 2mm. At the samemoment the largest deformation of landslide and bridge is 2mm·month-（-1） and 7mm·month-（-1）.（ 3） The deformation of bridge and landslide is synchronous. The monthly displacement difference is 0. 24 - 2. 13 mm. The cumulative displacement difference is 6. 3mm. Data and results of this paper has important significance to the management of Zhengjiawan landslide and the analysis of similar bridges across landslide.