Stress-strain state of the seam with zigzag geosynthetic diaphragm

Subject: despite the accumulated experience in the construction of ground dams with anti-filtration elements from geosynthetic products, the response of geosynthetic products in the structure of ground dams have been little studied. It was not determined whether positive stretch values can arise in the polymeric anti-filtration elements and whether they can threaten integrity of anti-filtration elements. For this, studies of the stress-strain state are required. The recent results of investigations of the physico-mechanical properties of contacts of polymeric geomembranes with soils allow us to study the behavior of geosynthetic products in the structure of soil dams. One of the possible designs - a high ground seam with a zigzag geosynthetic diaphragm - has been studied here. Materials and methods: investigations of the stress-strain state of the seam were carried out using numerical simulation. Calculations were carried out for a wide range of physico-mechanical properties of the geomembrane and the contact of geomembrane with the soil. The modulus of linear deformation of the polymer material, the angle of internal friction, and the tangent stiffness of the contact were varied. Results: the results of studies of the analyzed seam designs have shown that, in the main, the stresses in the geomembrane are determined by the modulus of linear deformation of the polymer material. The higher the stiffness of geomembranes, the higher are the tensile stresses in them. The shear characteristics of the geomembrane-soil contact are also important. The lower the shear strength of the contact, the higher are the tensile stresses in the geomembrane. Conclusions: the most vulnerable point of the zigzag diaphragm is its upper anchors, because it is in them that the greatest tensile stresses occur. It is recommended to turn them to the bottom side. In the diaphragm of the considered structure, it is impossible to use a geomembrane made of polyethylene; it is necessary to use a geomembrane made of PVC.