Study On Permeability Characteristics Of Soil Column In Remolded Soil

The occurrence of geological disasters is mostly related to the change of soil moisture content,which will lead to the change of soil strength.Rainfall irrigation can lead to a rapid increase in soil water content,so it is of great significance to study the law of water transport in unsaturated soil.This article through to the maowusu sand and loess infiltration characteristics research sense,experimental study on the mass flowmeter calibration method,built a monitoring monitoring water level laser water level gauge and seepage flow volume measurement barrel,the penetration test equipment improvement and debugging,infiltration characteristics research,migration regularity of soil moisture and the suction changes are analyzed,The following conclusions were drawn:1.The calibration method of DFM-1 flowmeter for recording infiltration flow rate in infiltration process is studied.According to the principle of mass flowmeter,find the actual flow and sensor to record the relationship between the phase difference,summarized a set to avoid the flow coefficient of the calibration,can operate simple and efficient calibration of flowmeter method,this method can carry on the correction for each flow rate error of range,and after a range of calibration errors are below 0.5%,And the use of the mass flowmeter steps and matters needing attention are summarized.2.A laser water level meter is designed to record the height of water level.The water level meter is based on the principle of laser rangefinder design,using water level float,sliding tube and other components,through the float reflects the change of water level and then laser rangefinder monitors the change of float height to measure the actual water level height,to be able to accurately and stably measure the water level height.The precision,stability and response ability of the designed laser water level meter are tested.3.3D printing technology can be well applied in the processing of some instrument parts.Compared with traditional manufacturing operations,3D printing has some unique advantages.In the production of laser water level meter,some special-shaped parts in the water level meter can be directly printed together.4.The results of indoor infiltration test show that the infiltration rate decreases rapidly at first,then slowly,and finally becomes stable.Through the change of the tension meter,water meter data and the change of the depth of wetting front camera,found that the moisture meter data before tension meter data changes,and the tension meter before the arrival of the data in the wetting front has slowly smaller trends,tension meter measured the depth of wetting front development than moisture meter on the depth of wetting front development of more accurate.The saturated permeability coefficient calculated by the formula of in-situ permeability test in code SL237-042-1999 is higher than the actual permeability coefficient,and the actual suction variation of soil is not considered.