Artists rendering of the Federation Tower, an aqua park, hotel and recreational facility.

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1 Artists rendering of the Federation Tower, an aqua park, hotel and recreational facility.

2 Diamond Technologies Contribute to the Construction of Moscow Manhattan The Moscow International Business Center is the largest investment and construction project in Europe, with a current value of $12 billion. The project, called by the business community and mass media the Moscow Manhattan, is astounding in terms of its scale and investments. This Moscow Manhattan is being erected on a 60-hectar area at Krasnopresnenskaya embankment and encompasses 15 high-rise towers housing office, trading and hotel premises, with a total area of 2.5 million square meters. Among the buildings which belong to the Moscow Manhattan ensemble, the most striking tower is undoubtedly the one named Federation, with its design height reaching 354 meters, 448 meters including the steeple. Once operational, Federation will become the tallest building in Europe. It was the project s prestigious location and investment intensity that caused changes to the original design of an indoor aquatic pool and office and hotel facilities to be constructed on plot No 4. The updated design and enhancement of a number of floors called for a substantial reinforcement of the foundations which also required partial reconfiguration. Using the technology of diamond sawing was the only expedient solution in this case.

3 The major challenge on the job was that the concrete cutting was being carried out simultaneously with the operations of blocks disposal, ground drilling out and driving of 1,200-millimeter-reinforced concrete piles into the holes to a depth of 30 meters. Foundation walls were wire sawed and cut into smaller blocks for removal. Schematic of the underground wire sawing set-up used on the pool floor. Stitch drilling was used on the fourth side of the floor blocks. View of the pool floor after a block is removed. The general contractor on this job was ENKA, a Turkey-based company known for its meticulous approach to the issues of quality, safety and timeline which hand picks its subcontractors and technologies. Limited access, dramatic heights, a very compressed schedule and the complexity of the job to be done all prompted the general contractor to choose Olvex, a CSDA member from St. Petersburg. The demolition would take place in three phases, each one unique in nature. The job commenced in the spring of According to the revised design, Olvex operators were confronted with a task to demolish the walls in the pool by cutting them off at a level of the pool s bottom. The major challenge on this job was that the walls, some of them being up to 5 meters thick and 7 meters high, contained a high percentage of mesh fabric, with wire diameter millimeters and a pitch of 100 millimeters, which on average reached a level of 12% of the cut surface. The walls were wire sawed from the foundation slab and side walls and further cut into 6-8 cubic meter blocks weighing up to 20 tons each. Given an extreme lack of working space, operators had to run Cedima CSA-1001 wire saws with a wire storage capacity of up to 21 meters. To haul the cut blocks from the pool, a ramp was built with some 3,000 cubic meters of fill dirt. The ramp provided access to the pool for trailers and other machinery. Truck-mounted cranes, with a lifting capacity of 150 and 300 tons, were delivered to take away the cut blocks. The total amount of cut concrete blocks that were hauled away by the general contractor during Phase 1 was 196, with a total weight of 2,700 tons. On this phase, the amount of reinforced concrete cut totaled 1,500 square meters. The second phase of demolition consisted of making openings in the bottom of the pool. At this stage, 280 openings measuring 1.4 by 1.4 meters were cut to a depth of 1.5 meters each, along with a few complex-shaped holes, in the pool s foundation bottom which measured 97 by 50 meters and 1.8 meters deep. It was decided that the best

4 Operators rigging a block for removal. Demolition work in full swing on Phase 1. technique for this demolition was plunge wire sawing which prevented weakening of the foundation slab. Olvex devised a plan which was offered to the general contractor for this cutting. According to this plan, three sides of each opening were cut through the foundation with plunge wire saws while the fourth one was stitch drilled. These holes measured 130 millimeters in diameter and 1.5 meters deep. Once this operation was completed, concrete breakers started pushing the block in the horizontal direction towards the stitch drilled side. 250 millimeter holes for plunge columns were cored with a set of 50-, 100-, 150- and 200-centimeter-long drill bits to a depth of 1.8 meters. For this job operators used hydraulic and electric drilling systems by Cedima and Hilti. Such an approach enabled operators to rip a 1.5-meter-high block out of a 30-centimeter waterproof substrate for the subsequent loading and disposal operation. The major challenge on the job was that the concrete cutting was being carried out simultaneously with the operations of blocks disposal, ground drilling-out and driving of 1,200-millimeter-reinforced concrete piles into the holes to a depth of 30 meters. The situation was further exacerbated by the fact that water and slurry could neither flow out of the pool nor soak into the ground. To pump water out of the 250-millimeter holes housing plunge columns for wire sawing, a few pumps were running continuously. In such punishing conditions, it took operators a lot of time and energy to start up the wire sawing systems. To make the deadline set by the general contractor, operators had to run up to 10 sets of wire saws, with the amount of wire sawed concrete totaling 2,700 square meters. It took operators and foremen a lot of concentration and skill to work under the pressures of limited access and tight deadlines, with foremen meticulously timing the shifts, lifting and disposal of blocks and aligning the company operations with the work of ground drilling teams. This reinforcement of the pool s foundation slab let the number of floors be bolstered to 65, up from 30 as per the original design. Schematic diagram of the horizontal wire sawing set-up.

5 View of demolition site nearing completion. The third and final phase of the demolition was a 30-meter-high, 6-meter-wide and 89-meter-long part of the building adjacent to the pool, with a foundation below. The demolition was being done in a close collaboration with other subcontractors and was considerably complicated due to the necessity to shore and brace the cut blocks. Due to a high leasing rate of lifting devices provided by the general contractor, the detached concrete structures were to be rigged and lifted away as fast as possible and that took a lot of planning from foremen. The building s slabs and walls were 20 to 60 centimeters thick, with columns measuring 50 by 80 centimeters in cross section. Since the foundation beneath this chunk of the building was about 2.5 meters thick, with a total volume amount of some 1,300 cubic meters, operators had to use tailor-made plunge columns, 3 meters long, when wire sawing a substantial part of the foundation. Operators were challenged to remove this slice of the foundation without deforming the building s remaining part. To strengthen the remainder of the foundation, the general contractor put a 0.8 by 100 meter chase in concrete for 30-centimeter metal piles to be driven to a depth of 16 meters, spaced at every 10 to 20 centimeters. Once this operation was completed, the process of the foundation demolition resumed. On this particular phase, operators sawed 2,300 square meters of concrete. The job was done 24 hours around the clock, with no days-off or holidays. Given the extreme working conditions, a smooth operation could only be possible through a scheme of rotating shifts and many experienced Olvex operators and engineers on staff. Over 150 operators of the company took part in this project. When carrying out the project, Olvex sawed 6,500 square meters and cored over 6,000 linear meters of holes of various diameters within 4 months. A total of 1,000 pieces and 10,000 tons of concrete were hauled away by the general contractor. Quality Management System ISO 9001:2000 and Occupational Health & Safety Management System OHSAS 18001, the implementation of which is currently underway at ZAO Olvex, contribute heavily to efficient coordination of the company s various departments, regular smooth two-way communication with general contractors and other contractors and meticulous observance of labor safety requirements. COMPANY PROFILE Olvex, a member of CSDA since 2005 has been in the diamond sawing and drilling business for 14 years. The company has over 200 specialists on staff with approximately 60 wall cutting saws and about 100 drilling systems. The company has eight regional representatives across Russia. Resources: General Contractor: Enka Insaat ve Sanayi A.S., Istanbul, Turkey Sawing and Drilling Contractor: Olvex ZAO (closed joint-stock company) Saint Petersburg, Russia Tel: / Fax: mail@olvex.ru or avb@olvex.ru Web: Methods Used: Wire Sawing, Wall Sawing, Core Drilling