Riverlinx CJV (BAM Nuttall Joint Venture) – Silvertown Tunnel

CA Drillers’ first project involved the deconstruction of the river wall. This challenging task required the implementation of vertical stitch drilling from the landside to sever the wall into detachable sections and subsequently be lifted out by the aid of Riverlinx machines. To ensure the River Thames, located underneath, remained free of slurry produced by the drilling and sawing, strict water and slurry control measures were employed.

Following that, we performed a series of operations on multiple areas on site. We have carried out floor sawing activities critical for initiating the open-cut procedure of the tunnel’s construction. Wire sawing was also conducted on existing UAE structures. Furthermore, we carried out a large quantity of pile cropping, we trimmed the pile tops to the necessary height using an effective combination of track sawing and Brokk demolition. It was essential that we was to retain the rebar within and not cause any damage, therefore the track sawing and Brokk activities was carried out with due diligence as to negate affecting the integrity of the rebar.

In addition, we was awarded the scope of works to demolish the Victorian dock wall which obstructed the trajectory path of the tunnel. For this, we employed a Brokk 400 & Brokk 800, to carry out the heavy-duty demolition task. More recently, we were involved in the headwall cut and carve operation. This operation was vital to prepare for the Tunnel Boring Machine (TBM)’s departure from Silvertown to Greenwich. This stage was a pivotal moment in the project, as it is when the TBM made its initial breakthrough at Greenwich after setting off from Silvertown, effectively forming the initial tunnel wall. In order to facilitate the Tunnel Boring Machine (TBM)’s successful exit, we employed a drilling and sawing approach.

This involved creating a series of drill holes around the circumference of the TBM machine and making vertical track saw cuts. The primary aim of this intricate operation was to weaken the structural stability of the wall. By doing so, we enabled the TBM to successfully penetrate and bore through the wall. This operation required meticulous planning and flawless execution, all of which were crucial in ensuring the TBM’s successful journey to Greenwich. We was provided short notice and time frame to start and complete. We received the phone call on a Friday with the intent to mobilise site on the Sunday and all works completed within the time frame of Wednesday. This achievement was a testament to our team’s dedication, expertise, and commitment to delivering high-quality work on schedule. (Please see pics below of the headwall cut and carve).