More certainty, less disruption

Better bridges, smarter locks

Our water-rich country has thousands of bridges and locks. Due to aging and more intensive use, many of these structures will be renovated or replaced in the coming years. This is how we keep the Netherlands safe and accessible. With 85 years of solid experience, KnookStaal bridges the gap between quality and predictable execution for the construction, renovation and maintenance of these steel structures.

Thousands of people use our country's many engineering structures every day. "There is no country in the world that has as many bridges and locks per square meter as the Netherlands," says Remmy Uffen, director of KnookStaal. "Many of these structures were built in the 1960s and 1970s, and are now eligible for large-scale renovation or even complete replacement. We have decades of experience in building, renovating and maintaining steel structures, ensuring that they are and remain safe and reliable."

Predictable execution

KnookStaal's credo is: we make bridges better. This is a nod to the replacement and renovation task of the coming years. "To fulfill that promise and achieve a makeable and predictable result, we like to be involved in the project as early as possible," says Uffen. "Here, we work intensively with regular partners who take care of the bridge or lock installation and civil works. Because often the control system needs to be replaced after 15 years and mechanical parts need to be overhauled. This is also the time for the bridge or lock to comply with the European Machinery Directive. A renovation is always accompanied by disruption and inconvenience, but with our experience we take into account the unexpected and prevent unplanned inconvenience. In this way, we guarantee demonstrable quality and predictable execution." 

Bridge Doctors

According to Uffen, many structures in our country suffer from overdue maintenance. "Monitoring and timely maintenance is essential to ensure availability and safety. Prevention is better than cure. We respond to this with our bridge doctors, who are on standby 24/7 for 'emergencies,' but of course also perform scheduled periodic inspections. We employ people with more than forty years of experience in this field. They have already taken care of many engineering structures and have specialized knowledge with which they can always find the cause. Periodic inspections of structures can be compared to a doctor's consultation. There are always things that come to light during the investigation. We report this to our client including repair advice."

Van Brienenoord Bridge

KnookStaal, as the name suggests, is originally a steel-oriented company. "We focus mainly on movable or fixed steel bridges," Uffen emphasizes. "A movable bridge is actually a large machine, where we work closely with established partners for the other disciplines. For example, we recently renovated the Oude Wetering bridge for the municipality of Haarlemmermeer as general contractor. We replaced the movement mechanism, made a number of adjustments and reconserved the bridge. The project was completed at the beginning of March this year. We are currently preparing to replace the wooden deck of the east fall of the Van Brienenoord Bridge. We are doing this with combination Sterk and the work will take place during the long weekends of Ascension and Pentecost. An operation where we work 24/7. On the underside of the bridge we erect a suspension scaffold from which we grind all 5,500 bolts for which we have developed special equipment. In order to work efficiently and predictably, we have developed a unique drilling line to pre-treat approximately 400 beams on site. A tough challenge, especially in terms of logistics."

From bridge to lock

At an earlier stage, KnookStaal was also responsible for replacing wooden beams on the west fall of the Van Brienenoord Bridge. "We're right at home on the well-known bridges in South Holland anyway, because together with Swarco we give substance to the contact Fixed Maintenance Movable Objects South Holland which includes ten bridges and four locks, including the Merwedebrug, Van Brienenoordbrug, Haringvlietbrug and Spijkernissebrug. We maintain, monitor and inform Rijkswaterstaat. In addition, we are on standby 24/7 with our emergency service." Other projects where KnookStaal has asserted its expertise include the new construction of the Michiel de Ruyter Bridge in Urk, a true eye-catcher, the renovation of the Lisser Bridge and the restoration of the historic Muntbrug in Leidsche Rijn. "Furthermore, we provide maintenance on the Krammer Locks and maintenance of bridges in various municipalities."

The above is just a selection of the many bridges and locks to which KnookStaal contributes or has contributed. It is rightly an all-round specialist with knowledge of the entire life cycle of structures. Moreover, they are extensively certified, such as for EN 1090-1:2009 to execution class IV and the Safety Culture Ladder step 4. "The latter is quite unique for the steel industry," Uffen says in conclusion.