Moving London safely forward

Paddington Station – famous worldwide not only for its creator Isambard Kingdom Brunel but also for a small marmalade loving bear. An average of 26,500 passengers travel from Paddingtion station every day. Despite its Victorian elegance and regality, plans were developed to build a brand new underground station directly beneath the historic landmark. This infrastructure project has been undertaken by Crossrail and forms part of Europe’s largest construction project. The new station will be known as the Crossrail Paddington Station.

Since July 2011, plans have been developed by Crossrail to complete a new underground network for London. In August 2011, working as a joint venture on behalf of Crossrail Limited, Costain Skanska was awarded Crossrail contract 405 to complete the complex £14.8 bn rail project. This project is creating a major new railway line, stretching 118 kilometres (approx. 73 miles) from Reading and Heathrow to the west of London, to Abbey Wood in the east. It will also pass directly underneath central London. The new network will now connect seven brand new mainline underground stations, all of which are important interchanges between existing Network Rail services and the London Underground. One of these new stations is the Crossrail Paddington Station.

Meticulous planning to monitor structures above and below
Working directly under the very heart of London has many challenges. The city is home to over eight million people and its underground handles a billion journey’s per year. The new Crossrail station at Paddington is surrounded not only by modern buildings but by historic ones as well. It is also located in the densely built-up zone of central London with its maze of pipes, cables and sewers, making it an extremely complicated construction project. Since London is considered a global city, it had to work without disruption, even for a project of this magnitude. Therefore, the Crossrail station is being built as a four-storey top down construction, with two-way live traffic above ground as excavation carries on below.

随着所有这些挖掘，伦敦中部松散的污垢可能会不均匀地定居，并可能导致结构倾斜或严重的裂纹。不断监测该地区的建筑物对于避免可能的损害至关重要，这就是Leica Geosystems产品和解决方案在通过监测结构和地球沉降程度来确保这条新铁路线的成功方面发挥重要作用。bob综合app下载

Robotic total stations observing Paddington 24/7
Costain-Skanska决定使用52 Leica TM30实施实时监控解决方案，尤其是用于监视设计的总站，以及在Paddington地区及其周围的所有类型的棱镜中超过1,800多个监测棱镜。bob apple设备附在建筑物外部的各个关键位置上。高度准确的3D数据是从总站收集的，这些数据衡量了整个地区建筑物中战略性放置的各种棱镜的关键参bob apple考点。这些测量值每天大约每天8,500点，每天进行。At the recent phase of the project which was called “the bulk dig”, the data capture for the majority of the area’s total stations takes place at six hour intervals each day, after which the data is sent to be processed with Leica GeoMoS, which sends the results to the web portal before they are distributed to the construction team. The use of Leica Geosystems monitoring sensors, software and communications is vital to the Crossrail project, as these accurate measurements provide information on any variations in structures caused by earth movement and minimise risks, not only to the buildings themselves, but also to public safety.

实时的自动数据处理
这样的项目需要持续观察,repetitively measuring the same routes and reference points several times daily throughout the entire project’s life span. By using robotic total stations such activities can be done automatically and data is directly transferred for processing using Leica GeoMoS, GeoMos Adjust and GeoOffice software.

Three interlinked servers are used to run the Leica Geosystems software programs at the Crossrail construction site. The software is used to detect and analyse ground movement and the deformation of buildings above and below the site, and also helps to speed up and simplify the processing of real-time data collected by the total stations by up to 90 %, allowing data to be available from field to issue quickly. This software solution for the new Crossrail Station is entirely from Leica Geosystems, and is the largest of its kind existing anywhere in the world. Engineering Survey Manager for Constain-Skanska Joint Venture, Steve Thurgood, reports
“The software systems have to be very prescriptive and procedural to control the quality and repeatability of the project, yet also allow for dynamic change in the environment and construction phase changes. Our operation runs non-stop, we manage the software system to minimise and repair any faults that might occur. Both software systems log a phenomenal amount of data which correlates with an astonishing degree of accuracy and precision.”

Leica Geomos软件解决方案是一个用于数据生成的全自动系统。它使用统计分析提供自动处理和评估，并使用易于理解的图表将新数据与原始基本模型进行比较。该软件还不断更新变形分析和网络调整，并使用44至49 *总站收到的大量实时数据进行调整，从而使高度准确的数据很快。bob apple

When the data is processed, it is additionally optimised by network adjustment software for co-ordinated geometry, topography and accuracy. Should any of the data not be within a ± 10 mm sphere of the previously collected data (generally not older that approx. six hours), it is considered incorrect. The engineering surveyors overseeing the operation evaluate and compare the data with deviations to the predefined data parameters and quickly decide if measures need to be taken.

与现场施工团队一起显示处理后的数据的协调有助于大大完成技术工作而不会受到干扰。Geomos不仅通过显示实时数据来增加生产率的正常运行时间，而且还通过在将数据发布给团队之前不断验证数据来简化工作流程。

Dedicated teams and reliable equipment
Dedicated round-the-clock operation and maintenance teams actively maintain the entire Crossrail project’s Leica GeoMoS software solution and also clean and maintain the 42 to 49 total stations and over 1,800 prisms. The total stations take six people to run plus an additional part time support staff of five persons in the field. All involved total stations are serviced and maintained at Leica Geosystems Service Centre in Milton Keynes.

“ Crossrail的座右铭是'向伦敦前进'。在我们的工程测量团队中，他们运行精确的级别计划和最大的Leica Geosystems在全球统一调整了总站计划，我们采用了一个补充座右铭，因为我们必须取得成功进行“移动测量以进行监视前进”。然而，如果没有Leica Geosystems及其供应链合作伙伴的持续支持，以上都是不可能的。

Written by Natalie Binder