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PANORAMAThe works were commissioned by the Architectural Heritage Sector of the Province of Varese, with the collaborationof the Achille Balossi Restelli Engineering Company in Milan. As early as the planning stage, it was clear that removingspoil from the tunnel would severely restrict the progress of the work. The inaccessible entrance, little room tomaneouvre and the need to lower a machine to a specific point using only the construction site crane narrowed thechoice down to a compact loader, as no other type of machine would have been able to work in these conditions.The contractors opted for a Bobcat T300 compact tracked loader, fitted with an anti-particulate filter by Bobcat dealerMAIE to reduce emissions in the tunnel. Together with a range of attachments, the T300 loader was purchased bySondrio-based ACCISA SpA, a specialist in this type of excavation work which acted as subcontractor to I.CO.P. SpA,the main contractor on the project, based in Udine.Massimiliano Duca of ACCISA, said: “We were looking for a compact loader which could remove spoil as quickly aspossible. The machine had to be powerful and have lifting capacities suitable for working in difficult conditions. Weightwas another problem: we had to partially disassemble the loader and lower the components to the tunnel entrance witha crane which had a maximum capacity of 1.6 tonne. With the assistance of MAIE, the loader was disassembled so thatthe largest and heaviest assembly, the main chassis, could be safely lifted by the crane. The machine was thenreassembled at the tunnel entrance to carry out the work and, at the end of the job, it was again disassembled toremove it from site.”BobcatUSACapital job forComansaOne Comansa 21 LC 400 towercrane works on the restoration ofthis historical building at a height ofalmost 104 meters (340 ft)JE Dunn Construction Company,the twelfth largest generalbuilding contractor in the UnitedStates, is managing the KansasStatehouse Exterior MasonryRestoration project, in Topeka,capital city of the state.This $36 million project, whichwill take 4 years, is a big challengedemanding good material hoistingaccess to all sides of the drum thatsupports the dome.The Capitol’s cruciform floorplan, the presence of otherstructures of the complex aroundthe building, an aggressive working schedule and the expenses of requiring multiple crawler cranes were optionsconsidered by the managers.The final solution was a single 21 LC 400 tower crane. It was erected with a height under hook of 103.8 meters (340ft), and a jib length of 80 m (262 ft), allowing the operator to reach every spot of the jobsite, and to move the jib over thestatue -a Native American archer from the Kansa tribe - that tops the dome at a height of 93 m (304 ft).To achieve this height without tying the crane to any other structure, a special tower configuration was designed: nine4 m wide sections (13 ft), one transition section, and other nine 2.5 m wide sections (8 ft).Blake Graham, project manager with JE Dunn, has said that it is currently the tallest freestanding tower crane inNorth America.Since the beginning of September, the crane, with 18 tonnes (39,683 lb) of maximum load and Flat-Top design, hasbeen at work transporting materials required for the restoration around the perimeter of the dome. The exterior masonryproject includes stone stabilization, crack repair, dutchman repairs, hand carving and others.ComansaContractors World Vol 1 No 9Page 7