充气时间和充气压力对土工膜焊缝剥离强度影响

土工膜焊缝剥离强度是整个防渗结构可靠性保障的关键因素之一。为了分析充气时间和充气压力对土工膜焊缝剥离强度质量的影响，选择7种不同厚度的HDPE土工膜在不同充气时间和充气压力条件下进行焊缝剥离强度试验。试验结果表明：在相同土工膜厚度和充气时间（3 min或10 min）条件下充气压力越大，焊缝剥离强度越小，土工膜厚度在0.25~1.00 mm范围内影响较大，在土工膜厚度1.00~2.00 mm范围影响较小；相同土工膜厚度和充气压力（0.1 MPa或0.2 MPa）条件下在土工膜厚度较薄范围0.25~1.00 mm内随着充气时间的增加剥离强度在减小，影响较小，在土工膜厚度较厚范围内1.00~2.00 mm范围内充气时间对剥离强度影响很小，可以忽略不计；相同充气时间和充气压力条件下，土工膜焊缝剥离强度随着土工膜厚度的增加而增大；土工膜焊缝工艺在土工膜厚度小于1.0 mm时，充气压力宜选择0.1 MPa；土工膜厚度大于1.0 mm时，充气压力宜选择0.2 MPa，充气时间可统一选择为10 min。

Effect of Air Inflation Time and Pressure on Geomembrane Welding Seam Peel Strength

Geomembrane welding seam peel strength is one of the key factors for the impervious structure reliabili-ty. In order to get the effect of air inflation time and air inflation pressure on geomembrane seam peel strength, in this paper, seven kinds of HDPE geomembrane with different thickness were selected to make the welding seam peel strength test at different aeration time and filling pressure conditions. The test results show that：Under the test condition of the same geomembrane thickness and the same air inflation time （3 min or 10 min）, geomembrane welding seam peel strength decreases with the normal stress increasing, having great influence in the geomem-brane thickness range of 0.25-1.00 mm and less influence on geomembrane thickness rang of 1.00-2.00 mm;Un-der the test condition of the same geomembrane thickness and the same air inflation prssure （0.1 MPa or 0.2 MPa）, geomembrane welding seam peel strength decreases with the air inflation stress increasing, having less influence in the geomembrane thickness range of 0.25-1.00 mm and less influence, even can be neglected, on geomembrane thickness range of 1.00-2.00 mm;Under the condition of same air inflation time and air inflation pressure, geo-membrane seam peel strength increases with increasing of the geomembrane thickness;In geomembrane welding seam technology,when the thickness is less than 1.0 mm, air inflation pressure should be 0.1 MPa, and when the thickness is more than 1.0mm, air inflation pressure should be 0.1 MPa, and air inflation time should be 10 min.