连接大陆

The third bridge above the Bosphorus, with its over 300 metre high pylons pairs, is a monumental masterpiece of engineering. It will help to reduce traffic between the Europe and Asian continents and is equally a symbol of Istanbul’s prosperity and economic growth. The Yavuz-Sultan-Selim Bridge is being built by the Turkish company, ICA Construction, and creates not only a motorway with a railway line, but also an additional connection for the transcontinental metropolis between the two continents. During the construction of the suspension bridge, the Leica Nova MS50 demonstrated its many diversified application possibilities.

ICA utilised the Leica Nova MS50 MultiStation, along with the Leica Viva GS15 GNSS receiver and other additional Leica Geosystems sensors, during construction for a great number of surveying, control and deformation measurements. With the new scanning function, the latest construction progress of the pylons could be compared with the architectural plans.

桥梁建筑中最高的桥塔
四个巨大的塔架连接了这座桥的子结构。它们的高度为309米（约1014英尺），是全球任何悬架桥上发现的最高的。两个倾斜设计的塔对完成桥的顶部，内部是空心的。每天，这些塔架生长约2.5米（8.2英尺），这对工程师来说是一个挑战，他们必须不断检查与塔架不断增长的外壳外壳的设计偏差。由于对施工要求的严格要求，只有很短的时间可用于检查塔架，但是，这些控件绝对必须进行。因为与设计的任何小偏差都会对桥梁结构的后续阶段产生巨大影响。

Leica Nova MS50的激光扫描函数和远距离测量用于确定针对设计的混凝土表面偏差，并使用Leica Cyclone Point Cloud软件进行处理。为了达到扫描数据的最高精度，MS50是在使用Leica Viva GS15 GNSS静态观察结果建立的控制点上设置的，并在Leica Geooffice中进行了处理。

另一个挑战是进行这项工作的严峻环境。Bosphorus海峡将黑海连接到马尔马拉海，工人必须与北部的寒冷风，以及雾霾和湿度抗衡，这可以在整个冬季持续。该项目使用的所有leica设备都可以轻松应对这些具有挑战性的条件。Leica Nova MS50的工作温度范围为–20°C至 + 50°C，IP65灰尘和防水。

High-quality measurements
大部分工作都是从三个地面控制点进行的。两个位于附近的山丘上，为塔楼和建筑工地提供了清晰的视线，每周进行位移控制，以检查坐标是否稳定，并与建筑设计的偏差进行比较。

另外，使用几个Leica TS30总站检查塔架的垂直比对。bob apple在施工期间从不同位置进行测量，以便在实时计划的实时验证准确性。

The Nova MS50 was set up over the control points, a scan window defined and a point cloud measured with a density of 1 cm every 100 m over a distance of 150 m. After collecting scan data from all sides of the pylons, vertical slices, created in Leica MultiWorx were checked against the design (CAD) data.

Fast and accurate scans
Surveying manager Yasar Hacieyupoglu commented, “We had complete confidence in the Leica Nova MS50 and Viva GS15 GNSS receivers to deliver the accurate long range measurement required for this project. The Nova MS50 is the only instrument which can scan accurately and at speed over the range required.”

“ Leica Geosystems一直是该项目的合作合作伙伴 - 建筑公司ICA，主要承包商现代工程。Endem Cons的测量团队都使用Leica Geosystems的产品，并且知道他们可以依靠他们从制造商和市场领导者那bob综合app下载里获得的支持，培训和服务。”

Written by Ruth Badley