强夯施工夯坑位置实时监测技术

Real-time monitoring technology on tamping pit position in dynamic compaction construction

强夯基础加固过程中,实际夯坑位置符合设计要求是保证地基加固效果的前提。针对传统强夯施工人工放样确定夯坑位置方法中存在效率低及成果校核困难等多方面的问题,提出了一种基于GNSS和地磁传感器的夯坑位置实时计算方法,研发了相应的夯坑位置实时监测系统。实现了强夯施工过程中夯坑位置实时精确定位。通过架设在夯机上的GNSS定位设备监测设备中心位置,同时利用磁方位角传感器获取夯坑相对于夯机的方位数据,进而对夯坑位置进行全过程、全自动的实时监测。针对时序夯坑位置信息离散的问题,采用空间聚类分析提取夯坑精确定位信息。以白鹤滩水利枢纽移民安置工程强夯施工实测数据为例,对该方法进行验证。结果表明,该技术能够有效确定夯坑坐标,提高了夯坑定位的智能化水平和效率,为强夯施工质量评价提供了有效依据。

During the reinforcement of dynamic compaction foundation,real tamping pit positioning satisfying design requirement is a basis for the reinforcing effect.Traditional manual lofting methods suffers several problems in determining the position of tamping pit,such as inefficiency and difficulty in result checking.This study develops a real-time method for calculating tamping pit position based on GNSS and magnetic sensors,together with a corresponding system of real-time monitoring on pit tamping.This system can realize accurate real-time positioning of the pit during dynamic compaction construction.It monitors the position of the monitoring equipment center via GNSS positioning equipment mounted on the ramming machine,using a magnetic azimuth sensor to collect the tamping pit azimuth data relative to the compactor,so that an automatic full-tamping-process real time monitoring is achieved.To discretize the time sequence of tamping pit locations,a spatial clustering analysis is used to extract accurate pit positioning information.This method is validated against the measurement of dynamic compaction construction for the resettlement project of the Baihetan dam.Results show that it can effectively determine the position coordinates of the tamping pit and improve the intelligence level and positioning efficiency,thus help the quality evaluation of strong compaction construction.