Drilling holes in the supports of the Severodvinsky bridge (44 holes in 2 hours).
During the reconstruction of the Severodvinsky bridge in Arkhangelsk, our customer Mostotryad-47 was tasked with performing diamond drilling of Ø132mm holes in the reinforced concrete supports of the bridge to a depth of 500mm. Number of holes on the support 44pcs. It is unlikely that such work can be called unique, if not for one BUT. The term of work is 2 hours!
The design solution for replacing old bridge supports with new ones included the drilling of holes using diamond drilling. Then a new anchor was glued into the hole on the EMACO repair mortar.
The work on re-supporting the bridge deck was carried out in advance, but the dismantling of old supports, site preparation, drilling and installation of new supports were carried out on certain dates. The road and rail links with Arkhangelsk were completely limited for a day.
An amount of time was allocated for each technological operation, which was strictly controlled by an engineer of Russian Railways and a representative of the company operating the Severodvinsky bridge. No more than 2 hours are allocated for diamond drilling. Mostotryad-47 has its own fleet of diamond equipment, but for objective reasons did not do the work on its own and turned to the specialists of DIAMONDTECH CONSTRUCTION.
The task demanded that every professional was busy with his own business, we were drilling, and bridge builders were installing.
As soon as traffic was stopped on the bridge and the lifting section was raised, we proceeded to unload the equipment onto the support and connect communications. One support could have 12 HILTI DD350 diamond drilling rigs and each required uninterrupted operation – nothing should fail, so many solutions were duplicated.
Somewhere the task was complicated by the fact that the drilling was going on old anchor rods Ф32mm. and it was impossible to move away from the marking. In such areas, we used three-phase powerful DD500 motors.
To avoid contamination of the bridge supports with sludge and get it into the river, it was collected by industrial vacuum cleaners in a separate container. Everything was organized in such a way that only one person was responsible for this, and two HILTI VC60 industrial vacuum cleaners served several installations at once.
The principle of minimizing personnel, which we lay as a basis at all facilities of the DIAMONDTECH CONSTRUCTION company, in remote regions of our country, where we have to solve diamond problems, is of paramount importance. The fewer people you need to work, the less the customer pays for their delivery and the safer and more efficient the workflow is.
The use of automated diamond drilling systems CutAssist has reduced the number of personnel to a minimum. Less than one person per piece of equipment.
In conditions where 6 diamond drilling rigs work in parallel on an area of 4m², cores are knocked out, the sludge is removed with a vacuum cleaner, the installation of metal structures and anchors are glued in parallel, and only 2 hours are allotted to work, and those at night, the principle of “minimum staff – maximum technology” plays a key role in the success of the project. Only specialists should be on site!
In October 2020, we made 2 visits to Arkhangelsk to carry out work on diamond drilling in the pillars of the Severodvinsky bridge. 8 holes were drilled in the first, 44 holes in the second.
Both exits are implemented strictly within the allotted 2 hour windows.
