The gray giant bites through. The machinist sits at the top of the driver's cab and controls the “recycler” with a joystick and steering wheel. The vehicle mills the new material into the road foundation, which will make everything go faster. 5.2 kilometers of road at half walking speed, there are only a few days left here on the construction site between Hohenwart and Freinhausen in Upper Bavaria: to get the mixture of mineral binder and cement into the ground, always injecting the exact amount of water, and keeping the front and rear axles on track with the man-sized rollers. And to prepare the ground for what's to come: asphalt.
Half a dozen construction vehicles are available for this purpose. A water truck hangs from the “recycler.” There is also a roller and a “grader” that brings the road to the required height. Two trucks whirl over dust and gravel. Instead of transporting away the old asphalt rubble like on conventional road construction sites, they deliver a mixture of cement and a binding material called Novocrete: 650 tons of it are distributed on the construction site, 25 kilograms per square meter. This means the old asphalt can remain in the ground.
This distinguishes the construction site from many others in the Federal Republic. If roads are renovated in the traditional way, tons of road surface and gravel are first dug up and transported away. This costs taxpayers time and money and also contributes to carbon dioxide (CO2) pollution. The new process using the binding agent Novocrete will halve construction times and costs, promises the manufacturer, IBS GmbH.
The binder is an example of research and innovation that former Transport Minister Volker Wissing (independent) called for in his road construction offensive. Because the expansion of the infrastructure consumes large sums of money. In the Federal Transport Infrastructure Plan 2030 alone, more than 130 billion euros were earmarked for road renovations. Additional investments from the special fund will be made.
New processes or products are rarely used in Germany, even though construction sites are becoming increasingly expensive. According to an analysis by the Federal Environment Ministry, the costs for road construction projects rose by 67 percent from 2015 to 2022. “World market leader in the niche,” says Julian Bihl, managing director of IBS.
The 34-year-old manager has just arrived at the construction site from Bösingen in Baden-Württemberg, where the company headquarters are. It was a good three and a half hours by car on the A81 and A8. The journey took a little longer than normal because tracks are being replaced on the route. Now it's just after nine o'clock and everything is already underway on the construction site. “Everyone likes good roads, but construction sites don’t,” says Bihl.
His father also thought that more than 25 years ago when he worked in a cement factory and was researching cement mixtures for road construction and repair. The father later set up his own business with his know-how and an idea: to reuse the old asphalt on site. Road builders talk about cold recycling. This has the advantage that no trips to the rubble dump are necessary. They went “to zero,” says Bihl. While in conventional road construction the subsoil is also excavated and replaced, IBS uses it further: the surface is milled, Novocrete is milled in, the foundation is compacted, leveled and watered. Asphalt is then paved. IBS launched the product on the market in 2010.
The medium-sized company now employs 20 people and can boast more than 2,000 construction projects, as well as several economic innovation awards. Nevertheless, Bihl says that it is a tough process in Germany to introduce other construction and renovation methods. The experiences abroad are completely different.
Novocrete was used for the first time in Switzerland. The company is currently renovating roads in Nicaragua, Argentina, Ukraine and Romania with the cement additive. There have already been construction projects in dozens of countries. Bihl recently traveled to China as part of a German business delegation. Chinese companies “have innovation in their DNA,” says the entrepreneur. In Germany, on the other hand, more roads were broken every day than were repaired. For Bihl, progress in road construction is therefore a fundamental decision for or against new methods.
There are some good reasons for conventional construction methods in road construction, says Konrad Mollenhauer, a professor of road construction at the University of Kassel. He is researching “in-situ” construction methods of cold recycling, in which materials such as the cement mixture are used directly on site for renovation. The fact that Germany sticks to the tried and tested has a lot to do with everyday procurement and administration, says Mollenhauer. Conventional road construction is very much determined by rules. Experts define the construction standard in the technical regulations.
To put it simply, the Research Association for Roads and Transport determines the construction methods that construction companies that apply for tenders should use. When a contract is put out to public tender, the cheapest offer wins. This is a success for the taxpayer. However, companies with new materials and know-how are at a disadvantage.
At the same time, the clients decide on the procedures to be used. The problem: There are no incentives to deviate from the construction methods of the technical regulations. If a new construction method fails, it is the client's risk, says Mollenhauer. Since road construction regularly involves millions of dollars, risks are avoided. Clients like Autobahn GmbH therefore fell back on conventional construction methods, says Mollenhauer: “What is in the regulations works.”
Road construction authorities in states and municipalities are, in principle, open to new construction methods, says the professor. However, their hands are often tied because financial support, for example from the federal government, depends on the technical regulations being observed. The bottom line is that new ideas in road construction are “very, very difficult”.
There will be a lack of 4.4 billion euros for motorway and federal road renovations by 2029
The entrepreneur Bihl knows that there is no way around the technical regulations and that this involves a lengthy, bureaucratic process. IBS has been trying in vain for more than ten years to have the binding agent Novocrete included in the regulations, even though Mollenhauer believes the building material works. “20 to 30 years” are not uncommon for new substances and methods to be included in the standard set, says the scientist. This also includes a certain amount of lobbying and committee work.
The regulations must ensure that construction companies nationwide can cope with the construction methods. Errors or problems must be ruled out. However, a much larger part of the road network could be renovated through cheaper construction methods. According to the Ministry of Transport's investment framework plan, 4.4 billion euros are missing by 2029 to finance all necessary maintenance measures for motorways and federal highways. In view of such figures, Bihl is calling for more openness to technology.
The managing director crouches down in a place that the “recycler” has already prepared. Then he shovels a fist-sized ball of cement with his hand. It is still moist and malleable. Asphalt can be applied in 24 hours when everything has hardened, says Bihl. A construction site of this size can be completed “in around two weeks” – instead of four weeks as in the conventional process.
