The assessment and analysis of the relationship between water pressure test and cement grout take at Seymareh dam grouting operation

One of the properties that evaluate in geotechnical reviews at rock mass, is the amount of permeability, that determine from water pressure test (WPT) and lugeon number. From the results of these test, use in determining of the amount of groutability in tunnel and dam site. Logical and practical relationship between amount of water penetration in Sections and cement grout take, leads to find prediction model of take amount in sections and so, necessity and the amount of grouting defined and will Cause to optimization of grouting operation in terms of technical and economic. In this study, using the Seymareh dam site data, relationship between lugeon number and grout take analysed. Then the effect of rock mass quality and depth of the grouting section to this relationship were studied. The results showed that in surface and much deep sections, penetration of water and grout, with correlation coefficients 0/86 and 0/82 have more relationship than central and deep sections, with coefficients 0/62 and 0/58. also in terms of quality of rock mass (according to RQD coefficient), in sections with very good and poor quality, these two parameters with correlation coefficients, respectively, 0/82 and 0/75, are closer together than good and medium sections with the coefficients 0/54 and 0/58. In central sections with state average quality, because of existence karst cavities and filling of joints and happening of hydraulic fracture, this correlation reduce.