CHAPTER VI--TEST INSTALLATIONS 60. Purpose. In addition to making tests on the fill to control embankment construction, test apparatus is installed in most dams built by the Bureau to determine the behavior of the earth embankment and appurtenant structures during construction and later reservoir operation. The apparatus permits measurements of pore fluid pressures in the embankment and foundation, consolidation of the embankment, and vertical settlement and horizontal alinement changes on the surface of the dam. 61. Piezometer Installation. the compacted impervious embankment, foundation gravel and sand, and in the shale bedrock. The installation included 12 foundation-type tips and 13 embankment-type tips. The tips were installed in shallow holes excavated in the compacted embankment (fig. 37). A total of 25 piezometer tips were installed in Figure 37.--Laboratory technician preparing plastic tubing for installa tion of piezometer in the embankment. P328-701-4711, Top of dam Variable -2" Std pipe coupling -2" Std. steel pipe 2" Std. pipe coupling "Holes -3"C 5 or equal Weld -Weld --3" [ 5# -2" Std. steel pipe "Steel plate -2" Std steel pipe-.. -Oakum -1" Std steel pipe See detail for base plate See installation drawing for location of apparatus in dam embankment Min. of 18" cover required over installation when 5'-0" lengths of 2" pipe are installed SETTLEMENT POINT LOCATION CHART 148.50' U.S. Axis El. 263.50' D.S. Axis El. Sta. 35+00.19 2710.71 64+00.69 2735.96 65+ 00.53 66+00.52 2736.92 67+ 00.44 2711.32 2711.61 NOTES For details of embankment settlement installation, see Dwg. 40-D-4414 Crest settlement points located downstream from the axis of the Elevations of all crossarms recorded to nearest 0.01 foot. At Sta. 53+00, Installation "A" installed as foundation settlement Original settlement point elevations established January and 148.50 D.S.-Stations 28+00 to 42+00, incl., and Stations 56+00 263.50 D.S.-Stations 27+00 to 43+00, incl, and Stations 57+00 Figure 40.--Settlement point installation details. (Sheet 2 of 2.) From drawing 328-D-980. |