Experimrntal Study On Similar Material Model Of Surrounding Rock Moisture Field In Expansive Rock Roadway Under Multi Source

In this paper,bentonite,quartz sand and barite powder were used as aggregate,gypsum were used as the regulator,and rosin alcohol solution were used as the similar material of expansive rock.Similar material specimen is prepared by compaction molding method.Sixteen experiments were designed by orthogonal test,the expansion characteristics and the water characteristics of similar materials were tested,and the feasibility of the raw material as the similar material of expansive rock was determined.The experiment shows that: the similar materials can satisfy the expansion and water characteristics of expansive rock.The third,seventh and tenth groups were suitable for weak,medium and strong expansions.Then select a suitable set of material mix ratio for model test.By heating and humidification and temperature humidity regulator setting model body inside water environment,working condition of roadway excavation simulation,the surrounding rock of roadway surrounding the moisture content of different direction monitoring stations.in this paper,the water content of the surrounding rock is measured by the method of high cycle wave,and the water content contour is simulated by the interpolation method of SURFER software to simulate the surrounding rock humidity field.In the laneway,there are two internal environments: the single water source environment with only floor water accumulation,and the multiple water source environment considering the floor water and the saturated water vapor in the air.The distribution of moisture distribution of expansive rock surrounding rock in multi-source environment is analyzed,and the distribution of humidity field in single water source and multi-water source is analyzed.The experiment results show that:(1)Under the condition of single water source,the middle line at the bottom of the roadway has the highest water content,the water absorption is fastest,and the water absorption depth is gradually decreased from the middle line to the corner.Roadway at the top of the no bibulous basic,there is water seepage phenomenon,but the penetration height is not high.At the same height,the closer roadway boundary moisture content is higher,the distribution of edge horn after absorbing water affects the moisture content of side wall of roadway;(2)In the condition of single water source,the water on the side wall of the roadway has a tendency to infiltrate the bottom plate.Under the condition of multiple water source,the water is diffused from the middle line of the roadway floor to the edge Angle,so that the water infiltration range of the corner is furthest,and it has a sharp Angle distribution.(3)A humidity field is formed around the surrounding rock of the roadway in the multi-source environment.When water absorbs 72 h in the bottom of the middle line,the water content is close to 30%;Perimeter will form a circle water,in water absorption model,material moisture content is the initial value unchanged from the outer circle,not affected by humidity field,tunnel wall due to near water,moisture migration is faster than the top;Roadway at the top and bottom of bibulous rate present instead of laws,roadway area at the bottom of the bibulous rate reflects a trend of slow down the first increases,at the top of the wall rock bibulous rate reflects the tendency of increasing with the slow,and the side wall of roadway surrounding rock bibulous rate before the top of the wall rock.The water diffusion depth of the side wall of the roadway is greater than the top side wall.