At the IACDS annual meeting, Douglas Walker from the USA was appointed as the new president of IACDS. Walker runs the American concrete cutting company Walker Concrete Cutting Services and has for many years played an active role in the American concrete cutting association CSDA, Concrete Sawing & Drilling Association, where he has, amongst other things, served as president. IACDS outgoing president Michael Findeis was thanked for his efforts since 2019. Due to Sweden's national association leaving IACDS, former treasurer Linda Dahlin was replaced as the association's new treasurer by Georg Lahofer. There were also reviews of the minutes from the previous IACDS annual meeting, the current status of the association and a presentation of an economic report.

After the meeting, the traditional networking event started where contractors and manufacturers from all over the world joined in. About 60 people mingled for about an hour until the ceremony for the IACDS Diamond Award started. The IACDS Diamond Award is an internationally recognised competition for the global concrete sawing and drilling industry which began in 2004. The Diamond Award now has three categories, jobs, products and public, to showcase the expertise of the contractors and the innovation of manufacturers. This international competition is organised jointly with the national concrete sawing and drilling associations. Following is a summary of the nominations for both categories.

 

Job nomination – Stone Divisor

The German company Stone Divisor submitted a project termed ‘save the wall’. The work involved perforating a 35m long brick wall, with 1.5m to 4m meters being drilled horizontally and up to 7m vertically at the site of the historic wall in Augsburg between Fischertor and Lueginsland which was threatening to collapse. To prevent this, both horizontal and vertical core holes were attached and then tensioned with steel rods. The job task was to perforate the wall with 250mm diameter holes as a blind hole for support discs. In this hole a 102mm diameter hole starts through the wall with 1.5m up to 4.5m deep. Until the wall was fixed horizontally to the ground, the contractor started with a 102mm diameter to drill through the wall vertically up to 7m with one piece core bit.

 

Job nomination – Antal

The second contribution came from the German contractor Antal and concerned the demolition of a former office building with a glass facade. Antal undertook the gutting, the partial constructive deconstruction of building areas and various building components, as well as the entire structural work etc. The dismantling of the two stair towers alone comprised a total 1,200m2 of saw cut area. In the process, walls up to 60cm thick were cut with the aid of several diamond wall and diamond wire saws, and crushed by a demolition robot equipped with concrete shears. In total, more than 15,000t of concrete was demolished in around six months.

 

Job nomination – Beton Bearbeitung Mahler

The third nominee was the company Beton Bearbeitung Mahler, also from Germany, which used a Husqvarna demolition robot to demolish the interior of a listed four storey building without damaging the exterior in a densely populated area. Accessing the building via the roof or the outer walls was off limits, so the renovation had to be carried out from the interior, from top to bottom. The first challenge was to get the equipment to the fourth floor via the staircase. The (Husqvarna) DXR 300 demolition robot is only 78cm wide, but the staircase was not much wider, with many twists and turns.

After the walls and lift shaft on the fourth floor had been demolished, the machines were moved to the next floor down. After arriving on the floor below, the demolition robot made the ceiling openings. Each of these included an opening of 60m2, requiring saw cuts along the outer walls, supports and beams for the existing structures. The staircase could then be removed upwards and all floors subsequently dismantled in the same way. Removing the entire 220m2 floor slab was the final task. Because of the densely populated pedestrian area below and the age of the building (1846) it was necessary to demolish all concrete and masonry walling without releasing any emissions. The debris was removed via the lift shaft.

 

Job nomination – Dymacore

The fourth contribution came from UK contractor Dymacore and concerned the renovation of an old bridge. Big Arch Bridge, built in 1813, strides Steelworks Road and is part of the Ebbw Vale heavy industrial heritage. The grade II listing reflects the bridge’s importance in the context of the area and is unmistakably massive. The arch measured 23m in length by an evolved intrados cross section of approximately 13m. The single span had an arch ring approximately 550mm in thickness comprising sedimentary stone laid with the bedding perpendicular to the line of thrust.

Goldhawk Ltd was invited by Blaenau Gwent County Borough Council to undertake trials of a methodology termed ‘interstitial grouting’ to determine the feasibility of injecting suitable resinous materials into and above the arch ring to provide a water resistant barrier. The aim being was to arrest the progress of freeze and thaw damage to the arch intrados. The trial was carried out from 9 March until 13 March 2020. Temperatures averaged around 6° with some frosty mornings and some sunny intervals. The trial was carried out following a period of exceptionally prolonged and heavy rainfall.

Following the trial it was determined that not only was water control installation required, but also a mechanical means of retaining some of the loose and friable masonry in place. Goldhawk Bridges Restoration, the sister company of Structural Repairs and Specialist Services was engaged to design and install a retaining ‘MARS’ reinforcing grid system into the soffit of the arch alongside the water control installation.

Following issuance of the instruction to proceed in November 2021, the services of Dymacore Ltd Drilling were engaged through a competitive tender process based upon it performance on other such contracts in the Reading, Bristol and Bath areas. On commencement of the contract, CADW (Welsh Heritage Board) required the local authority to take the repair further than the original scope, advising that the installed injection and retaining systems had to be ‘camouflaged’ into the structure. This in turn led to numerous trials and deepening of the required installations in the soffit of the arch barrel.

 

Job nomination – Re-Corta

The Spanish contractor Re-Corta undertook the advanced cutting of openings in galleries of a dam body. The job was part of the comprehensive rehabilitation works of the Vilasouto dam’s bottom drains. The dam was built in 1969, and is located on the Mao River with a volume capacity of 210Mm3. The bottom drains act as dam fuses, being requited to be able to control releases in case of safety problems in the system. The bottom drain flow must be bigger than the average river flow with a water height equal to half of the dam.  The Miño-Sil Hydrographic Confederation decided to undertake the project to ensure that the dam’s drains are operational and safe. The work consisted of removing the existing bottom drains, from the valve chamber to their outlet (downstream). This would require the opening of two parallel galleries, 1.20m wide, 2.13m high and 16.50m long. In addition, it was necessary to enlarge the valve chamber.

 

Job nomination – Behse betonbohr

The next job nominee was another German company, Behse Betonbohr, which undertook saw work with a circular wire saw at Fichtebunker combining several floors and with the exterior walls being opened up. The work was undertaken by Behse GmbH, with the opening of the outer walls being the technical highlight of the project. The wall had a total thickness of 2.50m, consisting of 2m of reinforced concrete and 50cm of masonry. The openings needed to be a height of 2.77m inside with a radius of 2m and a resulting width of 2m. Outside was a brick window arch, which was to remain as the stop of a new door. After the dismantling of the masonry in the window arch, a height of 2.35m with a radius of 1.17m and a width of 1.17m resulted. The wall thickness of the concrete wall to be cut was 2m.

 

Job nomination – D.I.M.A.S. Bohr- und Säge

The Austrian concrete cutter D.I.M.A.S. Bohr- und Säge carried out extensive drilling on the 430m long and 96m high Jauntal bridge over the river Drau, which is one of the highest railway bridges in Europe. The route is part of the Koralmbahn which is being renovated. The exciting thing about the project is that the holes for the injection work had to be drilled up to 20m deep through the foundations. The work for the tendons was carried out on the four bridge piers, which are between 60m and 77m high. In total, approx. 250m of boreholes had to be drilled through the foundations for the injection work, and approx. 1,200m of boreholes for the installation of tendons. The execution was planned together with the executing construction company which required timing and sequence of drilling. The selection of the appropriate drilling method and the required tool was coordinated on site. The Hilti hydraulic drilling system was used for the drilling, partly with automatic feed. Screw in drill bits from Tyrolit were used for the deep drilling. The difficulty was the drilling depth of up to 20m for the filling bores and up to 13m for the inclined bores for the anchorages.

 

Job nomination –Diamantbohr Group

The last job contribution came from Swiss Diamantbohr Group and concerned work with a mobile drilling unit for channel cutting in Blansko, Czech Republic. The Diamantbohr Group was awarded the job to create drainage sections (channels), some of which had individual lengths of over 20m. These were located in tunnel Nos. 7, 8.1, 9 and 10. The maximum cutting height above the setup position was specified as 8.5m. Diamantbohr Group’s workshop built a retractable arm system, which it then deployed to carry out the work. As a safety measure in case of a machine outage, a back-up plan was also developed. This consisted of a sequence of procedures that was worked out in advance. In this way it was possible to ensure that every single component that was relevant to the system was on site within a few hours. The aim of the emergency plan was to avoid any interruption over 24h. The tunnel profile cutter has a hydraulic drive power of 45kW with 320bar, and a maximum reach of 10.5m from the base of the machine (maximum cutting depth of 102cm). The cutting widths were variable and varied depending on the attachment, ranging from 0.50cm to 80cm in width.

Due to the applicable safety standards, the machine was built CE compliant and has a radio control induction sensor. Due to the complexity of the various aspects, four different attachments have now been developed, including a milling drum which can be equipped with up to 42 milling blades to a maximum width of 80 cm. The machine can carry an attachment weight of up to 485kg. The main challenge was the required height at which the cut had to be made (8.5m). Another difficulty was the distance of almost 1,000km between workshop and site. The sophisticated contingency plan was created to deal with any possible complication.

 

Product nomination – Braun Centrifugal Cutter

Six manufacturers were nominated for their products and product solutions. First out was Braun with its centrifugal cutter, BCC. The BCC is a special system for the mechanical and internal cutting of contaminated aluminium pipes of very small diameter for the safe dismantling of nuclear facilities. The extraordinary feature of the system is that the feed drive of the tools/saw blades is generated purely by centrifugal force, and not, for example, by an electric drive. This makes the machine ideal for the safe dismantling of nuclear facilities and thus represents a positive contribution to environmental protection. The BCC, in the course of a cold cutting process, enables the internal cutting of aluminium pipes that have a very small diameter. The machine can therefore be used for tasks where external cutting is not possible.

 

Product nomination – Dee Tec HBB2 diamond wire

The second product nominee came from Indian manufacturer Dee Tec and concerned a new type of diamond wire. The HBB2 diamond wire is a wire fitted with ‘HIP’ brazed beads (HBB) which features diamonds being placed with a very high concentration giving superior cutting life and speed. Diamond wires’ for construction applications is a high growth market with applications in concrete, heavily reinforced concrete, steel and offshore. Presently manufacturers include Tyrolit, Husqvarna, and Hilti. Machines are now being developed to be more powerful to allow the cutting of bigger surfaces at faster cutting speeds. Diamond wire is usually made with electroplated, vacuum brazed or sintered beads.

 

Product nomination – Dimacon

The third contribution came from Dimacon and concerned its software for the digitalisation of concrete cutting and drilling. Its smartphone and a web app has been designed to write daily reports, plan weekly, monthly and even yearly resource planning, write digital acceptance reports and safety checks (e.g. framework, guardrail). It is easy to photo proof, is attachable to the job and easy to understand and use. Dimacon is the first tool on the market in which the basic idea comes from a concrete cutting and drilling company. The programming was closely accompanied and evaluated by the requesting company and developed in close communication with workers and customers.

 

Product nomination – Edil Services watertight holes

Edil Services SRL presented it equipment for watertight holes on concrete tanks filled with liquid.

 

Product nomination – Maier Kernbohrtechnik Craftplan

The next product contributor was Maier Kernbohrtechnik with Craftplan which is a new soft work to simplify every day concrete cutting work.

 

Product nomination – Solga new dry cutting wall saw

The last product contribution came from Spanish manufacturer Solga. Its new dry cutting wall saw (C/S wall saw AL2 MS60 H10/2 O800 Laser E60 dry cutting diamond wall saw) was developed for high speed machines and calcareous reinforced concrete. For the development of this new product the company drew on its experience and other products on the market. The best diamond quality was used for cutting pre-stressed hollow core slabs and the bonds used in the stone market, which sometimes need dry cutting alloys for big diameter blades. The segment designed for its wall saws making it possible to create more gap between segments to increase the removal of dust created while cutting.

 

And the winners are

The winner of the IACDS Diamond Job Award was Re-Corta Démolición Técnica for the opening of galleries in the dam body for comprehensive rehabilitation of bottom drains. The winner of the product award was Braun Maschinenfabrik for Braun Centrifugal Cutter. The company Dimacon was awarded the Public Award for its new tool to digitalise concrete cutting and drilling companies.

 

The award jury and sponsors

The jury of the IACDS Diamond Awards 2022 contained Felix Plattner from the Austrian association VBS; David Potiron from the French association SEDDRe; Manfred Witzke from the German association FBS; Diego Tedoldo from the Italian association NADECO; Jun Ozawa from the Japanese association JCDSA; Fabián Acudia from the Spanish association AEDED; a delegate from the Swiss association SVBS; Colin Walker from the UK association DSA and Douglas Walker from the US association CSDA. Sponsors of the IACDS annual meeting and the Diamond Awards were Adamas, Gssi, Heger, Hilti, Husqvarna, Hycon, Lissmac, Siegenthaler Consulting, Solga and Stone Divisor.

After the annual meeting and Diamond Awards ceremony on the evening of the 27 October an informal dinner was held at the Bavarian restaurant and brewery Augustiner Bräustuben in downtown Munich.

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