Demolish with military precision 

In the A16 Rotterdam, structure KW58 was found to be in such poor condition that a support structure was urgently placed under it in 2022. Soon the idea was raised to replace the artwork in its entirety. To this end, two auxiliary bridges were driven in around King's Day and over the Ascension weekend. To make the latter possible, the Vlasman Demolition Works in a very short period of time to demolish part of the existing artwork with military precision. The high-quality Epiroc demolition hammers from Vlasman, supplied by Saes International, came in handy.

Vlasman Sloopwerken has been running for some time on the A16 Rotterdam. When it came to light in 2022 that the structure was no longer adequate and needed to be replaced, Vlasman was called in by construction consortium De Groene Boog. Rijkswaterstaat and the construction consortium carried out all kinds of variant studies to arrive at the most efficient solution for replacing the structure with the least possible disruption to traffic flow. During that phase, our expertise was requested for the safe demolition of the structure at a stone's throw from passing traffic on this busiest stretch of the Netherlands.

Demolish

Ultimately, The Green Arch opted for a solution in which traffic across KW58 was temporarily diverted via two auxiliary bridges. The auxiliary bridge for traffic in the southern direction of travel was constructed outside the traffic flow and put into service over the King's Day weekend. To install the auxiliary bridge in the northern direction, part of the existing structure first had to be demolished. We carried out that operation together with De Groene Boog during the 4-day road closure over the Ascension weekend. Because so much work had to be done simultaneously, we only had 24 hours to demolish the eastern part of the artwork. And so that could only be done from one side.

Demolition hammers

For the "24-hour job," Vlasman Demolition Works deployed an impressive collection of equipment, ranging from a 160-ton crane, a 70-ton crane, a 60-ton crane, three 50-ton cranes, two 30-ton cranes, a 25-ton crane, a 20-ton mobile crane and two 8-ton cranes. There were also five dump trucks driving for debris removal. Several types of demolition hammers were used for the crushing work. Two 7-ton Epiroc's HB 7000 stood in for the coarse work, and a third HB 7000 was rented from Saes International as a backup. After all, production was not to come to a halt under any circumstances. We also had two 4-tonne demolition hammers from the HB 4100 series and some smaller attachments. We purchased some of the attachments from Saes, our trusted partner for many years. It is a party with a large network and its own service and maintenance department. The latter in particular is of absolute added value to us.

Train 

On Thursday night, May 9, Vlasman started work on the project. A few weeks before the start, De Groene Boog found out that there was up to 1 meter thick asphalt. By mutual agreement, it was therefore decided to start a little earlier, so that we could begin demolition of the deck at 8 a.m. on schedule. We had exactly 24 hours to do this, because immediately after us a pile-driving team with two scaffolds started installing the piles for the auxiliary bridge, which had been pre-built by Civil Engineering De Boer in the armpit of the exit ramp. And that auxiliary bridge had to be driven in again on Saturday, May 11, according to schedule. The entire weekend was planned almost to the minute.

Chromium-6 remediation

Prior to the Ascension weekend, Vlasman was also flown in to remediate several chromium-6 containing components on KW58. We blasted a dozen bridge edges because of a Chromium VI component in the blue and gray coating. And right after the Ascension weekend on Monday, May 13, we demolished the west deck of KW58 between the two auxiliary bridges. Here the time pressure was somewhat less, which meant that we only had to work during the day. Nevertheless, even here we were faced with a deadline, because the following week the main road that lies under the auxiliary bridges had to be reopened. But, of course, that too was accomplished.

Intensive course

This December, Vlasman will return to the project to demolish the last foundations of KW58. Because the auxiliary bridge lies over this, we cannot reach it now. In total, we will then have demolished more than 5,000 m3 of deck. The concrete rubble was left on site, broken up and used as foundation material in the surrounding road network. Vlasman looks back on an interesting and, above all, intensive project. It was quite a challenge and organization to demolish so much in 24 hours. Two weeks before the Ascension weekend, we also gave a presentation to all the employees involved to leave nothing to chance. And that paid off.