Abstract:Geometric construction method determining valid vertical space in observation hole based on surveying data is derived. The computer programming method based geometric construction and the mathematical foundation controlling drilling construction quality of observation hole are introduced.

Abstract:Technical features, main requirements and process flow of sleeve valve barrel grouting method are described with the field cases of the method in grouting injection reinforcement, permeability proof and leakage treatment in china.

Abstract:The pull apart fissures appeared at the bottom side wall of the east slope in Yamansu open iron mine in Xinjiang. Based on the analysis of the side slope stability and the destruction model, design principle of pre stressed anchor method for reinforcing treatment of side slope weakened by explosion is described, and the anchor construction technology as well.

Abstract:During testing construction of high pressure jet grouting for reinforcing ebb gate foundation of Ji canal, through high pressure jet grouting around the defective grouting pile of ebb gate foundation, high strength complex pile shaft was formed. The method was also used for constructing the seepage proof wall on upper and lower parts of the floor of ebb gate. The void filling grouting under the gate floor guaranteed seepage proof stability and sliding resisting stability of flood gate foundation.

Abstract:Because of the lower rock fragmentation efficiency and defective geometrical shape of chisel bit, Sweden has replaced chisel bit with taper connecting cross chisel bit and button bit since the mid seventies. Now, we propose that chisel bit is renewed with more advantageous composite cutter bit gradually. The expected life of new series of bit is 2 to 4 times of that of the chisel bit and button bit, and the price is only one fifth to one third higher than that of chisel bit and button bit.

Abstract:Emulsion's effect mechanism on impregnated diamond bit's self sharpness is presented through analyses of experience and testing data in drilling with impregnated diamond bits in hard and compact ground.

Abstract:Evaluating quality classification standard of pile shaft by reflected wave method is presented based on dynamics and kinematics features of reflected wave. The cases of engineering application are listed and analyzed.

Abstract:The advanced anchor short cycle method used for solving the technical problems encountered while constructing tunnel branch portal in sandy and gravel formation is introduced. Safety technical requirements referring to state run road, pressure lifting station and the important buildings nearby are met.