Study on long distance upward sectional grouting borehole sealing technology of gas pressure test borehole

In order to solve the difficult problems to form gas pressure measuring chamber and to real and accurately measure the seam gas pressure due to a plug ea sily extruded from the month of the borehole with the traditional borehole sealing technology applied,under the gravity role of the borehole sealing material during the boreh ole sealing process of the passing through strata and long distance upward pressure measuring borehole,in combination with the actual seam deposition condition in No.6 Mine of Pingdingshan Coal Mining Corporation Limited,a sectional grouting borehole sealing technology of the passing through strata long distance upward pressure meas uring borehole was provided and was applied to E8-22310 coal mining face. The results showed that with the application of the traditional borehole sealing technology,the borehole sealing of No.1-3 pressure measuring boreholes was all failure and the boreholes were abandoned. The application of the sectional grouting borehole sealing tec hnology could not only solve the traditional grouting borehole sealing technology hard to be applied to the long distance and upward pressure measuring borehole and othe r difficult problems,but could have a high efficiency in the borehole sealing and the pressure measurement. Each measured gas pressure value would individually be a max报 value of 0.73 MPa from No. 4 pressure measuring borehole,0. 96 MPa from No. 5 borehole,0. 89 MPa from No. 6 borehole and was closed to the actual gas pressure1. 03 MPa. Due to the pressure measuring chamber with different distances to the coal mining face,the pressure released effect and each period keeping time of the pressure m easuring borehole would be different.