| Water inrush often occurs in underground engineering construction in complex strata.Grouting is the most widely used and effective method to control water inrush disaster.Previous researchers have done a lot of research on grouting materials,grouting technology and grouting theory.However,the diffusion and plugging laws of grout in complex strata are very complicated,and the grouting diffusion and plugging theories presented by different grouting materials are different.The relevant grouting theories proposed by scholars at present still cannot meet the actual needs of increasing grouting projects,especially the relevant research on the relationship between rheological properties of grouting materials and the influence of slurry diffusion and plugging mechanism under dynamic water conditions is relatively few.Therefore,based on the classification of water inrush types in complex strata and disaster analysis and prevention,this paper introduces a new grouting material-viscosity time-varying grout for the special needs of grouting engineering in dynamic water rock mass fissures.Anton Paar advanced rheometer is used to study its rheological properties and influencing factors.A series of dynamic water diffusion tests are carried out through grouting simulation equipment.The diffusion pattern of viscosity time-varying grout and the working mechanism of grout blocking rock mass fissures under dynamic water conditions are clarified.Combined with relevant research conclusions,the water inrush disaster in Guling tunnel is successfully controlled and certain research results are obtained.(1)According to the stratum conditions and water inrush characteristics of underground engineering,the types of water inrush from underground engineering are divided into four standards,namely,water source,water inflow variation characteristics,water inflow and water guide channel,and the characteristics of different water inrush types are described in detail.(2)Based on the pumpable period and setting time performance of viscosity time-varying slurry,the orthogonal test was used to test the primary and secondary effects of different additives and their dosage on the slurry performance,and the optimal ratio of additive dosage was determined.On the basis of this ratio,the effects of water cement ratio and additive 2# and 3# single factor variables on the rheological characteristics of viscosity time-varying slurry were studied in more detail,and the viscosity time-varying equation and rheological model of slurry were obtained.(3)Through the detailed introduction and feasibility analysis of the grouting simulation device independently developed by the team,the diffusion test of time-varying slurry with viscosity under dynamic water condition was carried out.Considering the influence of slurry viscosity change,rock mass fissure inclination angle and grouting parameters on slurry diffusion and plugging,the diffusion formula and slurry layered deposition plugging theory under dynamic water condition were put forward.(4)Based on rheological characteristics of viscosity time-varying slurry and slurry diffusion and plugging theory,combined with gushing water disaster types of Guling tunnel,controllable grouting technology is adopted for grouting treatment,and the effect analysis after grouting treatment proves the applicability and high efficiency of the viscosity time-varying slurry for treating high-pressure strong water gushing. |
PDF Full Text Request