first, composite geomembrane's construction method, 1, construction preparation 1) composite geomembrane materials quality testing, this project used composite geomembrane is two cloths film one film composite geo-membrane, 2) clean up embankment slope, flat ground, remove all sharp corner sundries, backfill and tamppile the slope is qualified acceptance after supervisor, providing working surface for the pavement of composite geo-membrane. 3) as for geomembrane split joint, for the sake of convenient construction, ensure the quality of split joint, composite geomembrane should as far as possible use wide range, decrease the field splice quantity , before construction, in accordance with the requirements of composite geomembrane width and scene length demands, it should be cut inside the unit, and spliced into the required size block, to roll it on the steel pipe, manual handling it to the working face. 2, 1) composite geomembrane pavement, 1) the laying method of composite geomembrane, compound geomembrane pavement is divided into paving of canal bed and slope paving two parts. Paving method: rolly paving it in axis direction of canal. slope paving, after qualified acceptance of slope, roll along the axis of the slope, and connect to composite geo-membrane in T-shape. 2) composite geomembrane's paving technical requirements:
The composite geomembrane construction process: one. Foundation surface excavation. two, geomembrane pavement, three. align the welding seam, four welding. Five, scene inspection, six repair, seven, reinspection, eight, backfill soil
Composite geomembrane pavement, welding construction scheme. first, the composite geomembrane anti-seepage structure design 1, composite geomembrane specifications choice, composite geomembrane specification selection is relative to cushion layer flatness, material allowed tensile stress, elastic modulus, maximum water head within the paving scope and the maxiamum particle diameter of coverage layer and so on, the thickness of the geomembrane design should consider the strength of the water pressure requirements, also the service life of the exposure, bury, climate, such as application conditions, and according to the current national regulations on standard to determine the design thickness and the actual thickness. 2, composite geomembrane anti-seepage structure layer design, the dam upstream slope composite geomembrane anti-seepage structure from top to bottom, in turn, is 40 cm slurry masonry surface, 180 cm filter material layer, 30 cm overlay layer of sand- gravel material, composite geomembrane, 30 cm gravel material bottom cushion?ply, the largest diameter of filter material filler coarse sand gravel is less than 350mm, the largest diameter of upper and lower cushion?ply filler fine sand gravel is less than 10mm, the particles with a diameter less than 0.075mm in gravels is less than 5%; anti-seepage cladding region composite geo-membrane seepage-proof structure in reservior from upper to lower is 80cm gravel layer, 30cm overlay layer of sand- gravel material, composite geo-membrane, 30cm gravel lower cusion layer, the diameter requirement of filler is the same as dam upstream slope.
