障碍水的桥梁 - 使用激光扫描捕获德国阿尔卑斯

作者：托马斯·肖克（Thomas Schock）

HöllentalkLamm-在英语“地狱的峡谷”中 - Garmisch -Partenkirchen附近是德国阿尔卑斯山高1,000m的独特自然景象。It’s part of the hiking route to the Zugspitze peak, a connection only made possible due to a historic bridge across the gorge, built in 1905. Due to its age and deterioration, the bridge and several footbridges had to be replaced in 2020. The local members of theGerman Alpine Association (DAV)为250,000-Euro项目筹集了资金，并找到了两个关键的公司赞助商 - 运输基础设施专家ZÜBLIN / STRABAG和Thyssen-Krupp.

Strabag是Leica Geosystems的合作伙伴，使用激光扫描解决方案以数字方式捕获新的桥梁。该调查表明，即使在这种“地狱”环境中，扫描仪的表现能力也是如此。创建的数字计划将用于将来维护。

Replacing an historic and much-loved bridge

The construction of the first bridge over the gorge took 600 working days to complete, from 1902 to 1905. An impressive feat of engineering, it was completed almost by hand, without electricity or modern machinery. Today, the build materials could be delivered by helicopter at least to the Höllental entrance at 1045m. From there the team, made up of ZÜBLIN / STRABAG engineers, local construction company Florian Dörfler and DAV volunteers, needed to drag the components to the construction site 200m away. To transport the bridge, which weighed over four tonnes, into the narrow gorge, it was divided into some 600 individual parts. The custom bridge and walkway elements were prefabricated by ZÜBLIN’s Structural Steelwork subdivision in Hosena, Brandenburg.

Despite almost perfect preliminary planning, a few obstacles were inevitable. Removing the rock where the bridge supports were anchored proved to be significantly more difficult and time-consuming than expected. Nevertheless, the build took only four weeks. ZÜBLIN site manager Philipp Schön sums up, “The preparations and finally the execution of this sponsorship project against the very special backdrop of the Höllentalklamm was really fantastic. The teams from the various project participants worked wonderfully together, like pieces of a well-oiled machine.”

A portable, robust and highly accurate laser scanning solution

一旦取代了桥梁，Strabag的技术集团经理菲利普·米尔克（Philipp Mielke）与约翰内斯·泽特尔（Johannes ZettelLeica RTC360和BLK2GOto capture a digital twin of the new arch bridge using laser scanning.

RTC360在高度便携的同时提供了干净且高度准确的点云。实际上，它与碳三脚架一起安装在背包中，并从停车场远足到峡谷。它也很健壮-IP54的额定值，因此能够应对水的溅水 - 非常适合湿山环境。

BLK2GO是一种手持式成像激光扫描仪，在移动时会重新创建3D空间。操作员-Schock-能够一只手携带并在行走时进行扫描，从而轻松保持平衡并意识到湿滑的地形上的危险。用于处理数据的软件是Leica Cyclone REGISTER 360,Leica CloudWorx,Leica TruView Enterprise和Leica Cyclone 3DR.

From bridge capturing to data sharing

Using the RTC360, Schock carried out scans across five viewpoints: three scans were taken on the bridge, two on either side from 50m away, looking towards it. This created a picture of both the bridge and the rocks of the narrow gorge on all sides. HDR images were taken with the scanner at five exposure stops to allow for an RGB inspection for dark areas (tunnels) and bright areas (those in full high-altitude sunlight). Speaking about the unusual conditions, Schock says, “Surefootedness and a head for heights are required in the Höllentalklamm! But the ascent was quickly mastered with the lightweight RTC360.”

Using the BLK2GO handheld imaging laser scanner, Schock completed several walks taking around 10 minutes, covering 150 - 200m of terrain on each side of the bridge. This was done with enough overlap in the connection areas to allow for the linking of successive trajectories with the Cloud2Cloud algorithm from Cyclone REGISTER 360.

扫描后，使用Cyclone寄存器360用于导入，准备和优化数据，以提供在其他Leica Geosystems和第三方应用程序中使用的LGS数据集。Truview Enterprise用于可视化，这是一种与项目中的其他人共享点云数据的快速简便方法，Leica Cyclone 3DR将用于隔离峡谷和隧道的数据。

即使在“狭窄和约束条件”中，令人印象深刻的结果

The Höllentalklamm bridge project was an ideal opportunity to put the latestLeica Geosystems 3D laser scanning equipment进行测试。尽管该位置难以访问，而且天气状况具有挑战性，但激光扫描仪与海平面一样易于使用。

Schock says, “Both scanners performed as expected and the results exceeded expectations.” Philipp Mielke from STRABAG agrees, “Results of the bridge scan using the RTC360 were very good. We had no problems in scanning the bridge even in these cramped and constrained conditions.” The company is already using the RTC360 in other tunnel and construction projects and further tests with the BLK2GO are currently in progress or planned.