Temporary infrastructure for medium and low voltage N206

With more than forty years of experience in construction site equipment, Theo Hartman of Bouwtech BPI knows the ropes by now. Still, even for him, the temporary infrastructure for the sunken location of the N206 ir. G. Tjalmaweg was "a special one." 

The N206 Tjalmaweg is part of the RijnlandRoute. "For the first part of this extensive work, we were allowed to participate in the tender with the international contractor combination Comol5," says Hartman. "After being awarded the contract, we were allowed to fully realize the temporary infrastructure. In that sense a nice crowning achievement for our work that we were then invited by Boskalis to also make a price for the construction site design for the last part of the RijnlandRoute, the N206 Tjalmaweg."

Aluminum instead of copper

Bouwtech BPI specializes in building the temporary infrastructure for water, electricity, sewage and data. "We are often called in as early as the tender stage to fly and budget the construction site design as efficiently as possible," Hartman continues. "We therefore work for all major infrastructure contractors in the Netherlands and are involved in a wide variety of projects. The fact that we can take care of both medium and low voltage is an expertise that is almost non-existent under one roof in the world of temporary site facilities. We arrange everything from A to Z, create the design, budget and ensure timely execution, within budget of course. In terms of medium and low voltage, we work exclusively with aluminum. Aluminum is lighter and easier to process than copper. It is also 30% cheaper and less prone to theft. However, aluminum does require just a little more space, but we design accordingly."

Simultaneity

The biggest challenge for Bouwtech BPI lay in the fact that the grid operator's infrastructure was only present at one point. Hartman: "The distance that then had to be bridged to provide the 2-kilometer-long sunken location with a certain connection capacity requires the necessary knowledge and expertise. We have that, for many decades, in-house." On the north side, Bouwtech BPI realized a 400 kVA /630 ampere connection that is guaranteed all the way to the terminus, due in part to the well drainage along the entire length (200 kVA), the two mixing stations of 100 kVA each and MIG welding activities of 100 kVA with a certain simultaneity. On the south side of the sunken basin, two more separate 165 kVA/ 250 ampere connections are provided for the chain parks. In terms of medium voltage, the setup consists of a dedicated installation with 1 set-up transformer from the grid operator and then to the left and right two set-down transformers to reduce voltage loss and cable thickness."

In all, Bouwtech BPI provided the total temporary infrastructure on the north side in a time frame of just three weeks, ranging from 4,600 meters of single core medium voltage cable and over 3 kilometers of low voltage cables. Layed "We also provided the temporary water installation," Hartman adds. "In doing so, we had the water supply company lay four connection points to provide the pressure and capacity of 15 m³ constant and from all points to be able to construct a water line of 63 HDPE that is still reasonably manageable. We can maximize our knowledge and expertise and feel at home on such complex and challenging projects. The cooperation with Boskalis here on the N206 is therefore going smoothly and we have even already started dismantling certain segments."