Garage worn safe again

Q-Park is investing heavily in refurbishing the structure of the Q-Park Haagse Mart parking garage. This was urgently needed, because the steel sheet pile walls that form part of the main supporting structure were rusting. Gebr. de Koning from Papendrecht took on the challenging job, because the parking garage had to remain operational during the renovation. 

"There was quite a bit going on," begins project manager Marcel de Keizer. "In the parking garage, pre-walls had been installed in front of the sheet piling. This probably caused humidity and accelerated rusting." When this was seen during inspection, it caused quite a shock. "The intermediate floor of the 2-story parking garage was primarily supported by these sheet pile walls, which also serve as a ground retaining structure, so action really had to be taken."

Q-Park worked out a repair plan together with consultancy firm Hageman BV and Gebr. De Koning, with Gebr. De Koning also taking on the execution. "We are specialists in concrete and sheet piling, both small and large. That's why we hooked up here, too." The steel in the parking garage was first cleaned and blasted. The intermediate floor was fully temporarily supported so that the old support attached to the sheet piling could be removed. Then concrete walls, with both structural and preservation properties, were poured against the full sheet piling contours. "These walls partially take over the function of the sheet pile walls," says Dr. K.

Improvising and working small

That the more than 450 parking spaces in the Heemstraat parking garage remained open during the renovation created quite a challenge, according to De Keizer: "As a result, we had to come up with new solutions and improvise. However, non-standard projects are also what we like best. In a project like this, we can show what we are worth and what we can do." During the garage renovation, the goal was to minimize the inconvenience as much as possible. "Actually, no one realized we were working. For example, we chose to pour concrete on the two days the garage was closed. A concrete mixer was on the driveway, then we used a small mixer pump and up to 180 m of hose to get the concrete to the right place." This concrete had to be smoother than normal to travel the distance through the hose.

Formwork was needed to pour the new walls, but getting it in the right place was not easy because of the location. "The garage is two meters high, so bringing heavy formwork inside with a crane was not an option. So we started thinking small in this project and working with small equipment and small materials." So Gebr. De Koning purchased a small electric shovel, which was exactly 1.99 m high, so it could just barely get inside. Reinforcing steel was transported with a small trailer that could just about fit inside. For the formwork, Gebr. De Koning chose the Peri-duo box. "This is a plastic box that is manageable by hand, and can be easily built up in small segments. With all these clever solutions, everything we needed to do worked. We look forward to completion with confidence."