Scanning high-traffic roads unmanned

作者：Kiew Tian Lim

新加坡土地运输管理局（LTA）的座右铭是We Keep Your World Moving。该组织致力于建设大规模快速运输（MRT）系统 - 汤森 - 东海岸线（TEL），该系统增强了从北到南走廊的轨道连通性切割。新的捷运线将大大提高中央商务区和码头湾地区的可及性。

TEL的建设大大改善了通勤者的旅行时间，其中包括从伍德兰兹北站到垫圈贝多克车站的43公里的地下隧道。在双三车道重型交通电路（SLE）下方有4.5公里的隧道（SLE），监控至关重要，而承包商将确保可忽略不计的道路变形或干扰会影响交通流量。

The engineering firm Tritech Engineering & Testing (S) Pte Ltd was contracted to monitor the road surface with a fully automated monitoring system on a real-time basis. To provide this service, due to critical circumstances and high stringent monitoring requirement, Tritech initiated with Leica Geosystems’ monitoring solutions.

Laser scanning and total station in one

使用徕卡没有va MS60 MultiStation plus Leica GeoMoS monitoring software v6 and later, Tritech was able to set up an Automatic Road Monitoring System (ARMS) covering a two-kilometres critical stretch of the SLE affected by drilling of the Tunnel Boring Machines (TBM) underneath. The essential laser scanning functionality of the Leica Geosystems MultiStation combined with reflectorless and prism measurements came to the rescue, as prisms installation on the road, which is prone to destruction by passing vehicles, was not an option for this project.

“With the MS60 MulitStation, we were able to setup the ARMS, enhancing productivity as an unmanned measuring system,”Tritech Engineering＆Testing（S）PTE的注册测量师Tor Yam Khoon博士说。有限公司“该系统还可以作为一个有效的测量系统，在测量时期完成后不久就可以无线提供结果。”

The automatic scanning ability of the system enabled quick delivery of deformation information. With GeoMoS image-assisted scan area definition feature, the firm was able to add the defined areas to the measurement cycle. For the firm, this combined solution helped enhance:

• 准确性和可靠性；
• 快速解释监视数据；和
• Correct remedial decision making.

“Leica Nova MS60 is a good hybrid of total station and laser scanner useful in deformation monitoring of points using glass prisms and surfaces using new Leica GeoMoS n.Vec Technology. In this project of road surface monitoring, successful application of the n.Vec Technology to horizontal surfaces is well demonstrated,”said Dr. Tor.“It is definitely better to derive the vector of deformation from a scan patch of at least 500 readings rather than from a single reflectorless reading.”

在Tritech专有的自动化结构化监控系统中，对项目中使用的八个多阶段​​的数据进行了整理。自动监测系统，具有四个小时周期的能力，每周7天，对多阶段和地缘人来说，可以转化为减轻人工成本的主要成本。

Data was collected from MultiStations set up at the road shoulder on a 4-m-high observation platform at the middle of four rows of patches of road surface at 25 m apart. These four scan patches were defined in rows crossing the road over the white lane markings. These 16 regular scan patches are monitored at regular intervals. Between each 25-m regular monitoring zone there were also defined with “standby” scan patches at 5 m apart. These standby scan patches will be added to the monitoring scheme for automatic monitoring cycles whenever there is a planned or unplanned cutter head intervention. While the above MultiStation is in active monitoring, another one will be setup ahead and ready to go when the TBM enters its monitoring zone.

支持from abroad

For such a precise setup, there were initial challenges. Leica Geosystems staff in Singapore worked diligently with support staff in Switzerland to quickly diagnose the setup issues and effectively resolve them.

“When there was a need to change the MultiStation in the midst of the monitoring campaign, there were no adverse effects to the project due to a timely and effective response by Leica Geosystems technical support,”said Dr. Tor.

监视solutions by Leica Geosystems support LTA to fulfill its promise and keep the world moving wherever heavy construction projects are underway.