双压力传感器埋入式沉降仪的研制及应用

针对传统沉降板在高速公路软基沉降观测中存在干扰施工、操作繁琐等弊端,提出了一种双压力传感器埋入式沉降仪。该沉降仪基于将土体沉降测量转换为对密闭系统内液体压力变化测量的原理,主要由竖向密闭管、基准传感器和路基传感器构成。通过室内试验和现场试验,详细阐述了其在标定、埋设和数据采集等阶段的操作方法。研究结果表明,该沉降仪的测量精度可达2 mm,重复性误差2 mm。与传统沉降板方法相比,其主要优势有:(1)该沉降仪埋设在土体中,与地面施工互不干扰;(2)只需分别采集双压力传感器的读数,测量效率高;(3)可用于工后沉降的长期观测,测量成本低。

Development and application of a new embedded settlement gauge based on dual-pressure sensors

Since the traditional settlement plates have adverse effects on the construction with tedious operations, a new embedded settlement gauge based on the dual-pressure sensors is proposed. Based on the principles of transforming the measurement of ground settlement to that of variations on hydraulic pressure in a full-sealed system, the new embedded settlement gauge comprises a vertical sealed pipe, a standard pressure sensor and a core pressure sensor. Both laboratory and field tests are conducted to describe the detailed operation instructions, including calibration, installation and data collection. It is found that the new gauge is applicable with a precision of 2 mm and repetition error of 2 mm. Compared with the traditional settlement plate, it has several significant advantages: (1) It is embedded underground, thus there are no effects on construction; (2) The settlement can be measured only by reading the sensors, resulting in a high efficiency; (3) It can be employed to measure the post-construction settlement, leading to a low cost.