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<br />- <br /> <br />001084 <br /> <br />the 6- by 13-foot fixed-wheel gate shall be performed. If the situation is more urgent, one <br />employee shall immediately begin closure of both ring-follower gates and another shall start to <br />close the 6- by 13-foot fixed-wheel gate. High flow testing shall cease. <br /> <br />'j <br />II <br /> <br />7) To accomplish high flow testing (both hollow-jet valves above 500 fiNs), a minimum of <br />three individuals shall be present. Either the Dam Maintenance Supervisor or his appointed <br />representative shall be present. Two individuals shall be present at the main outlet works With <br />radio communication at all times. There shall bea minimum of two dependable vehicles at the <br />main outlet works at all times, to help ensure immediate access from the outlet works valve <br />house at the toe of the dam ,to the gate house at the dam crest. <br /> <br />The following actions should be performed for the tie rods prior to conducting operational tests of <br />the main outlet works : <br /> <br />1) Perform non-destructive test on tie rods. - Both the top and bottom areas of the two tie <br />rods adjacent to the inner surface of the 110-inch-diameter pipe should be inspected for cracks <br />using the dye penetrant technique. This is to determine whether vibration damage has already <br />occurred. If damage is present, it should be repaired before any testing takes place. <br />Scaffolding will be required to reach the top area of each tie rod. It will take approximately <br />two days to perform the inspection and non-destructive tests. <br /> <br />2) Perform modal survey of tie rods. - A modal survey of both tie rods should be performed <br />to determine their natural frequencies. This would take about a day, and would be performed <br />inside the unwatered 110-inch-diameter pipe. <br /> <br />3) Perform operational test on tie rods. - An operational test should be performed, similar to <br />that performed at Palisades Dam. Both tie rods should be instrumented with strain gages <br />located at the tops of the rods. Discharges through the two hollow-jet valves would range <br />from zero up to the maximum possible discharge. From this test we should be able to <br />determine whether either one or both of the tie rods is accumulating any fatigue damage from <br />vibration. If structural fatigue is occumng, this may indicate a limit for the discharge, or some <br />other action may have to be taken to ensure the structural integrity of the pipe. This test <br />should be scheduled sometime this winter to ensure that the data will be available for further <br />study of discharge capabilities through the main outlet works. Installation of the Strain gages <br />will take one day, while waterproofing wili take one day to apply ~md three days to cure. <br />Installation of the test instrumentation requires the 110-inch-diameter pipe to be unwatered. <br /> <br />If approved, operational testing of the main outlet works would be performed in stages up to 100 <br />percent valve opening. During each stage, the valve opening, discharge, reservoir level, and <br />tailwater level should be recorded. If the auxiliary outlet works or power plant is to be operated <br />as part of the planned release, hydraulic conditions in each basin should be monitored during the <br />test. Observations should be made of the general flow patterns on the apron, and ofthe wave <br />action along the shoreline of the downstream channel. Eddy patterns should also be noted in the <br />power plant tailrace and spillway stilling basin. Interaction between the operation of the different <br /> <br />27 <br />