Multi-mechanism And Prediction Of Mechanical Parameters Of Rock Mass Under Complicated Conditions

With the continuous development of infrastructure construction in China,the underground engineering,slope engineering and tunnel engineering under complex geological conditions increase year by year,which poses great challenges to the on-site rock mass investigation and design and engineering construction safety.Seek a highly efficient,rapid and accurate for rock mechanics parameters of the technology and methods is the modern rock mechanics study and engineering application of force to solve problems,based on this,this article about li ning,a professor at the team of research and development of a new generation of XCY-2 rotary sounding device,using different rock stress state and failure pattern of rock cutting mechanics model,The transformation relationship between drilling parameters,response parameters and cutting force was constructed.Related researches were carried out in combination with the rotary cut penetration test,and the following innovative achievements were obtained:(1)Research on rock mechanics parameter prediction method and in-situ stress calculation method considering the stress state at the bottom of holeBased on the single pole in the process of drilling rock stress and stress analysis of shear plane is developed,with the consideration of cutting force under complicated stress state and the drilling parameters,response parameters,the theoretical formula between rock mechanics parameters,the influence factors of cutting force analysis of the single pole,puts forward the prediction method of rock mechanics parameter and the horizontal in-situ stress and vertical stress calculation method.(2)Research on cutting mechanics model and rock mechanics parameter prediction method considering rock failure formAccording to the rock-breaking characteristics of single diamond tool of diamond-impregnated bit,the cutting mechanics model of single diamond tool with or without breaking zone in rock-breaking process and the theoretical relationship model between cutting force and drilling parameters and response parameters are established.Four kinds of rock mechanical parameter prediction methods were proposed based on no friction in no broken zone,no friction in no broken zone,no friction in broken zone,and friction in broken zone.The influence of broken zone and the number of broken zone on rock mechanical parameter prediction and response parameter feedback was analyzed.In the model in this paper,the weight on bit and torque required to cut the rock with the same depth and strength by considering the broken zone are larger than those by not considering the broken zone.If the broken zone exists and is not considered in the calculation of rock mechanical parameters,the predicted cohesion will be larger,and the greater degree is proportional to the actual number of broken zone.(3)A new study on the correlation between drilling parameters,response parameters and rock mechanics parameters based on rotary shear penetration testBased on professor li ning team designed and developed a new generation of XCY-2 rotary penetration drilling system,and puts forward the constant rotary cutting instrument-speed test of standard penetration test plan,conducted the granite,the rotary penetration test of concrete specimens,reveals the correlation between drilling parameters and response parameters,rock mechanics parameters is verified the effectiveness and accuracy of the prediction method.Under the condition of constant speed,stable WOB and torque increase linearly with the increase of ROP.Under the condition of constant ROP,stable WOB and torque decrease linearly with the increase of ROP.When drilling in the same rock mass,the WOB-torque relationship is always a linear function,which is not affected by rotational speed and drilling rate.Use of drilling parameters,the response validation test for four kinds of rock mechanics parameters prediction model,the fourth model(consider broken zone and friction)predict cohesion and internal friction Angle is the most accurate,errors are within 30%,the uniaxial compressive strength of granite error is 12.1%,C35 uniaxial compressive strength of concrete error was 15.3%.(4)Research and development of XCY-2 rotary shear contact rock mass intelligent analysis systemBy introducing the drilling response parameter statistics and the calculation method of drilling specific work value,the rock intelligent classification platform is created.Based on different bit cutting mechanics models and rock mechanical parameter prediction methods,Platforms such as PDC bit single tool cutting force prediction and optimal dip Angle selection,PDC bit rock mechanics parameter prediction,diamond impregnated bit single tool cutting force prediction and optimal dip Angle selection,rock mechanics parameter prediction of diamond impregnated bit were established.Finally,XCY-2 rotary contact rock intelligent analysis system was integrated.Intelligentized analysis of shear penetration parameters and fast acquisition of rock mechanics parameters are realized.