“In my professional life, I often took the curve”, jokes Karl Hammerschmidt of DB Schenker in Hagen. For the head of heavy and special transport this is more than just a casual saying, but part of his core competence. To make it around the bend! With a 150-ton colossus on the road, the topic takes a serious turn. Vehicles as long as half a football field and roughly 10 meters in width are not to be sneered at. Not to mention 7 meters up. That is when you realize how tight it can be under bridges!
By car, you can take every turn no matter how tight it is. If necessary, you back up and make it the second time. This is different with a 50 meter trailer. “That’s why, long before the start of the transport, we need to know where the radius of a bend is critical, whether all the bridges bear our weight and where the overhead line hangs too low,” explains Hammerschmidt.
A taboo for sidewalks
A permit is needed anyway for every heavy transport. The authorities want to be sure that the planned route is a good one. The use of sidewalks is forbidden. For who knows what burden it is designed for? Its ground is not nearly as compact as that of a roadway. If there is a power cable or a water pipe, a small misstep of the heavy transporter can cause unpleasant consequences. Therefore, notice: The unauthorized use of the pavement is definitely not a trivial offense. If police is around, this may mean a ticket and, on top of that, some points in Flensburg. If approved, the world will look different. Sometimes it is conditional. For example, it is possible to cove the sidewalk with steel plates.
Head of Heavy and Special Transport, DB Schenker
“Digital route planners and simulation programs are extremely helpful. Nevertheless, you have to see the critical points in advance with your own eyes.”
The age of digitization has produced useful helpers for route planning and traceability analysis. For instance, there is the possibility of making 3D scans of bottlenecks. Such documentation leads to simulation trips, which give a binding information about whether the transport can be realized as planned. “Of course, we make use of the technical innovations,” says Hammerschmidt. But each scan costs. With complex bottlenecks there is a lot on the table – just to convince yourself, the client and the authority that the truck does not get stuck somewhere. Depending on how long the route is and how many bottlenecks “are in the way”, we are talking a lot of money.
TTBN – Through the bottleneck
Therefore, Hammerschmidt considers another new form of route planning: Based on a conventional route planner (Google Maps), the Objectfab in Dresden developed a tool by the descriptive name “Through the Bottleneck”. The web-based program has collected information on a number of “bottlenecks” and continues to stock up on the resources of the users. In addition, it relies on the relevant data of the vehicles in question, such as weight, steering radius and altitude. The user virtually defines and loads the combination of tractor and semitrailer provided by him. Then he drives off the possible route on the screen. TTBN “knows” how much space the truck needs for which maneuver. Even at first glance at the selected route, the dispatcher receives information about problem areas. He then takes a closer look. The program allows him meter-accurate simulation of steering maneuvers. It indicates if and how the vehicle can pass the critical point. This type of documentation is also convincing to the authorities, accelerating the approval process for a heavy transport quite a bit. And: It is significantly cheaper than 3D scans.
“Respect for the curve”
Tools such as 3D-Scan and TTBN are now highly mature. “It helps us enormously with the route planning,” says Hammerschmidt. But, of course, the veteran does not rely blindly on digital information. He still uses a well-tried tool from the analog world. Which one? In very tricky places Hammerschmidt uses the … folding chair. Yup! “I sit down for an hour at the bottleneck and observe in peace, what happens there.” He calls this “respect for the curve”.
Head of Heavy and Special Transport