在伦敦的天空中精确定位

作者：Renata Barradas Gutiérrez

City landmarks are not built overnight. In between planning, design and construction, there are other crucial activities - just like monitoring and positioning - happening at the same time.

22 Bishopsgate, a287-metre-tall skyscraper, rose through the air in London’s financial district in the United Kingdom. Planned with the ambition to be the capital’s first ‘vertical village’, 22 Bishopsgate isLondon’s second tallest building。

To construct the cores that make this landmark rise, Careys Civil Engineering, a well-known construction company with a proven track record of delivering projects that enhance the built and natural environments of communities and infrastructure in the United Kingdom and Ireland, delivered the concrete works using a self-erecting jump form system – the first of its kind to be used in the UK.

Building62 storeys, with a floor space of more than120,000 square metresrequired Careys Civil Engineering to pour58,000 cubic metres of concrete并使用7,500吨加固。在如此庞大的复杂而充满挑战的项目上蓬勃发展需要创新的方法论

- 就像为Leica Geosystems为Careys土木工程开发的建筑定位系统一样。Careys土木工程设计为跳跃高层建筑的量身定制解决方案提供了参考坐标，以监视和执行施工期间的测量任务。

Doing it the Careys’ and Geosystems’ way

22个主教的两个核心墙是由Careys土木工程制造的，该墙壁工程师使用跳跃形式系统进行了几种混凝土倒入。跳板系统是工作平台或钻机，用于修复模板，钢固定和混凝土。该系统适用于高层结构中多层垂直混凝土元件的构建。

After each jump, or elevation of the rig to build a new level, the Careys Civil Engineering surveying team needed reliable coordinates to proceed setting out the structure and verifying the correct positioning of the core. The main task of the automated positioning system Leica Geosystems created is to obtain precise and reliable coordinates during the entire construction process that are not influenced by the movement of the building.

This tailor-made GNSS-based monitoring solution consisted of:

• 七Leica GM30 GNSS receivers for monitoring
• 七Leica AR10 GNSS antennae
• Leica GeoMoS Monitor
• Leica GNSS Spider software
• HxGN SmartNet reference station network
• Tiltmeters

通过上述硬件和软件组合，Leica GeoSystems使用GNSS观测值与倾斜度计（精度倾斜传感器）一起开发了一个程序，以在上升摩天大楼的形式的顶部获得可靠的协调点。Leica Geosystems机器人总站可以看到这些协调点或主动控制点（ACP），以设置其坐标和方向。bob apple

“在伦敦市中心的一定高度以上，地面控制点不再可用或可见。GNSS系统能够提供可靠的坐标，而无需地面控制，” said Damien Watson, senior engineer at Careys Civil Engineering, Plant and Fleet department.

To set up the automated positioning system, GNSS stations were coupled with Leica Geosystems 360-degrees prisms, so the positioning information provided by the GNSS sensors was available to be used as reference points for the surveyors performing the survey of the core wall with Leica Geosystems robotic total stations.

高精度倾斜仪,固定在同一locations of the GNSS antennae, were coupled to the GNSS station to track the verticality of the GNSS antennae in order to provide, at each computation, the most accurate coordinates. SmartNet network was used to provide reference coordinates to the GNSS stations on the rigs and compute the baselines.

确保流畅的数据流

To obtain the ACP, data was collected, stored and post processed with Spider Software at a dedicated PC to deliver the most accurate coordinates for the team. Spider is the control centre software where positioning information was computed. The data from the GNSS stations on the rig and data from the SmartNet Reference Network was combined to provide every six hours the most accurate set of coordinates for each point for Careys Civil Engineering team. Spider coordinates were automatically transferred to GeoMoS Monitor where they were transformed into local coordinates and adjusted based on tiltmeters data.

“The Leica Geosystems solution allowed for a fully-automated workflow and computation of the results and fast delivery of coordinates when required, optimising costs and time of operation for the surveying team compared to different methodologies,” said Watson.

此外，该团队能够实时检查蜘蛛界面中每个单点的卫星数量和数据质量。所有这些质量检查实时提供了高水平的定位测量准确性，使土木工程建造该地标所需的地标需要。

每个跳跃和处理期之后，机器人总站都可以使用新的有效控制点坐标来测量结构中的任何标记或对象。然后，现场的Careys土木工程团队继续在所有控制点都可以看到机器人总站。

The robotic total station determined its own position and orientation observing the control points and checking the results with the coordinates given by GeoMoS. In this way, the robotic total station observed all relevant points to be checked during the construction.

建立在上升

Accurate and reliable positioning on the status of structures displayed as actionable data is crucial to make fast and informed decisions and react to potential problems. The GNSS-based monitoring system has proven so successful that Careys Civil Engineering will be using it in future projects, such as the construction of a new tower in Manchester.

“徕卡呈规则的解决方案automatically delivered reference coordinates to the surveying team when needed, and the accuracy got better and better while the structure was growing building confidence after every jump,”concluded Watson.