LST MULTIPLE FILE DRIVING RIG (BARGE MOUNTED)

DUE TO THE UNAVAILABILITY OF AN LST, IT WAS DECIDED TO TEST THE GENERAL FEASIBILITY OF THE MULTIPLE PILE DRIVING CONCEPT ON A PONTOON BARGE, PRIOR TO TESTIN ON AN LST. ALTERATIONS TO THE DESIGN WERE SUBMITTEED BY THE CONTRACTOR FOR THE PURPOSE OF MOUNTING THE DRIVING ASSEMBLY ON THE STERN OF A DOUBLE-TIER, 10 X 24 PONTOON BARGE. SUBSEQUENTLY, THE FABRICATION AND MOUNTING OF THE MULTIPLE PILE DRIVING RIG WAS ACCOMPLISHED AT, AND BY, THE LABORATORY. THE ENGINEERING EVALUATION CONSISTED OF MOORING STUDIES AND THE DRIVING OF PILE BENTS. RESULTS OF THESE TESTS INDICATED THAT THE MECHANICAL AND STRUCTURAL DESIGN WAS UNSATISFACTORY AND THAT SATISFACTORY MOORING OF THE BARGE FOR PILE DRIVING OPERATIONS WAS VIRTUALLY IMPOSSIBLE, WITH PRACTICAL AND ECONOMIC LIMITATIONS. IN VIEW OF THE TEST RESULTS, FURTHER TESTING OF AN LST IS NOT WARRANTED