Research On Drilling Technology Of Soil Environment Sampling In Shallow Layer

With the development of modern earth science,especially environmental science,more and more attention has been paid to soil environmental problems.The geological environment survey project and the implementation of the 13 th five-year plan for land and resources have put forward new requirements for soil environment survey and protection functions.In order to support the construction of ecological civilization and serve the people's livelihood,it is necessary to carry out soil environmental investigation.Shallow soil environments sampling techniques is an indispensable technique for soil environment investigation.The main technical characteristics of shallow soil environment sampling are: the sampled strata are quaternary overburden;the high quality requirement for samples;Sampling is generally within 30 m.Shallow sampling drilling is the most effective means to obtain shallow soil samples,and its technical difficulties are: the rotary drilling method will cause disturbance and pollution to soil samples,and the sampling heart rate is insufficient;existing non-rotary sampling equipment is heavy and bulky,not conducive to movement and transportation,environmental adaptability of which is poor.In this paper,in order to meet the technical characteristics and requirements of soil environmental sampling,combined with technical difficulties of shallow drilling,audio frequency vibration and impact drilling mechanism and portable sampling equipment and technology were studied,a set of drilling equipment and process method to solve the problem of sampling within 30 m soil environment were formed to solve the problems of undisturbed sampling of soil environment and lacking of portable equipments.For the vast majority of soil environmental investigation,drilling sampling is from the loose soft formation within 10 m.Based on the design ideas of portable,high quality and high efficiency drilling sampling,a 10 m drilling rig with high efficiency sampling by means of audio frequency vibration and associated drilling tools and processing method were developed.The drilling rig has the characteristics of small size,small weight and high drilling efficiencyFor the compacted clay layer and sand layer within 30 m,a 30 m impact sampling drilling rig,auxiliary drilling tools and process method were developed.The hydraulic drive impactor is adopted for impact sampling,equipped with single and double pipe sampling drilling tools,which can realize non-disturbed sampling of soil samples within 30 m.The rig is designed with modular combination structure;the weight of the module is less than 100 Kg,which is light and easy to handle.Through the application demonstration of audio frequency vibration type and impact type portable drilling rigs combined with the project,the performance of the drilling rigs has been verified to meet the design requirements,the coring quality and efficiency are high,giving full play to the advantages of light.The development of two types of drilling rigs solves the key technology of portable drilling rig for non-disturbed environment sampling,fills the gap of the lack of portable non-disturbed sampling equipment for soil environment sampling in China,and improves the service level and technical support ability of shallow sampling drilling for soil environment survey.