One team with the same goal: The synergy of precast and concrete construction in Strijp TX 

De Kock Betonbouw and De Kock Prefab BV are working as one team on the development of Strijp TX. "We are constantly looking at where we can optimize processes to deliver more value," said project manager Tim Conrads. Together with precast coordinator Henry van Hulst, he explains how they do that.

Conrads: "Strijp TX is the largest project we as De Kock Betonbouw have ever taken on. In the existing Philips Building TX in Eindhoven, we are building the shell structures of three office towers, each 30 meters high." Van Hulst: "We do that with a combination of cast-in-place concrete walls and precast walls, columns and beams from our own factory. In total, we make all 1,500 precast parts of this work all by ourselves." Conrads: "We chose to do this because there is a very tight deadline on the completion of this project. By producing the precast parts ourselves, we are independent of third parties and can better guarantee the continuity of the overall project."

From drawing to production

Conrads: "Our work starts as early as the engineering of the precast elements. The main contractor's structural engineer shares the initial drawings with us, and our work planners then convert them to production drawings including pour-in provisions." Van Hulst: "After the client's approval, we proceed to production. We build the formwork, place the reinforcement and pump the concrete. At night, we let the material harden properly and in the morning we loosen the boxes. Then the whole cycle starts all over again." 

Conrads: "Because we practically sit next to each other in the office, we can switch very quickly. That's great, because even now that we are in the implementation phase, the design still changes regularly. Recently, for example, columns of 60 by 60 centimeters suddenly had to become 60 by 80 centimeters, because this was architecturally more attractive in the building." Van Hulst: "The day such a change comes in, we can immediately make new production drawings and immediately schedule the new designs for pouring. And that's what we want, because we have the same objective: for the exterior to be flawless." Conrads: "With an outside party, you would then have to first seek agreement on price. But we work in the same interest and want to prevent the work outside from grinding to a halt at all costs, so we take action immediately." Van Hulst: "We had the columns adjusted and on site within 5 working days."

Advantages for vision work

Conrads: "Another advantage is that we pour both the walls and precast elements with the same concrete mix. In this project, that comes in particularly handy because we are dealing with a lot of visible work: the building will have an industrial look and both the precast columns and beams and the walls will remain visible." Van Hulst: "We also apply the same pouring method in the factory as on construction. With an outside supplier there was a chance of color difference in the concrete, but with us the look of in-situ and precast concrete is pretty much the same."

Conrads: "On other projects, we also deliver finished precast elements directly." Van Hulst: "Then we don't apply lifting devices, but move the precast elements with our vacuum lifter and special suction cups. As a result, we don't have to finish anything after installation and are able to deliver a high-quality element immediately. That saves time AND is tighter to the eye." Conrads: "So we are actually continuously looking at where we can optimize processes to create more value for the customer. In addition to Strijp TX, we are also doing this as a total structural contractor for 58 apartments at Wolfskamerweg in Vught and three high-end residential towers at Triadome in Leidschendam-Voorburg." Van Hulst: "The latter is extra special because of the white decorative concrete we use for the facade elements." 

De Kock Betonbouw is a contractor of complete structural work projects. From small precast elements to complete structural skeletons and exposed facade elements.