三峡库区界桩测设特点

Surveying and setting up of boundary markers for TGP reservoir area

三峡库区库岸界桩测量与埋设,具有5大特点:①界桩测设涉及淹没实物指标补偿的敏感问题,按《长江三峡工程初步设计水库淹没实物指标调查大纲》的要求进行界桩测设,保持其一致性至关重要;②库周两岸长近6000km,涉及湖北省、重庆市的25个县(市、区),干、支流线路长,界桩测设工作繁重,且承担测量和埋设单位多,项目管理难度大,需要规范施工程序管理;③库区干、支流交错,合理布设界桩并保持其成果的统一,以达到既保证测设质量,又使成本开支最小,既考虑各区域的特点,又保证全库区的统一;④三峡库区地形地貌复杂,交通运输十分困难,施工环境差,界桩测量精度要求高,测量设备的先进性和测设人员经验、素质十分重要;⑤库区埋设界桩4万余座,且移民周期长,故界桩属永久的基础设施。

The survey and embedment of boundary markers of the Three Gorges reservoir possesses five features:① the survey and embedment of boundary markers relates to some sensitive problems on compensation for inundated physical objects,therefore,in accordance with requirements of 《Investigation outline of tangible material indices of reservoir inundation for preliminary design of the Three Gorges Project》,it should be kept consistent for all the boundary markers;② the reservoir bank line is about 6 000 km,involved with 25 counties (cities,districts) of Hubei province and Chongqing municipality,the work of surveying and embedding boundary markers is arduous,the institutes to survey and embed the boundary markers are numerous and the project management is difficult,so the management of construction procedure should be normalized;③ in the reservoir area,the main river and branch river crisscross,so the layout of boundary markers should be reasonable and the results should be kept consistent in order to guarantee the quality of survey and enbedment,minimize the cost and take features of all zones into consideration;④ because of complicated topography and geomorphy,difficult communication and transportation,bad construction environment in the Three Gorges reservoir and higher requirement for survey accuracy,advanced surveying instruments and experienced qualified surveying and embedding personnel are important;⑤ in view of over 40 000 boundary markers on the reservoir bank and of a long construction period,all the boundary markers belong to permanent infrastructure and the management of boundary markers is an arduous task.