Multi-connected flexible wall permeameter
Technical Field
The invention relates to a multi-connected flexible wall permeameter, which is mainly used for the permeability coefficient of a soil sample.
Background
Traditional flexible wall permeameter is by penetrant unit, the air water is kept apart and is supplied liquid device, the exudate metering tube, data acquisition processing system and atmospheric pressure source are constituteed, penetrant unit and air water are kept apart and are supplied liquid device and air compressor machine to be connected respectively through air supply line and air-vent valve, penetrant unit is kept apart and is supplied liquid device and exudate metering tube with the air water through the permeate liquid pipeline respectively and is connected, data acquisition processing system passes through signal line and pressure sensor, temperature sensor is connected with penetrant unit, pass through signal line and exudate volume sensor and be connected with exudate metering tube. The flexible wall permeameter needs single pressurization operation, a large number of air pumps are needed to be configured when the permeability coefficients of a plurality of soil samples are tested, and the workload of test operators is large. If the permeability coefficient of the soil sample in a uniform environment needs to be tested, the air pressure state of each flexible wall permeameter is difficult to keep synchronous and consistent.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a multi-connected flexible wall permeameter, which is more labor-saving in operation, and can synchronize and make the air pressure of each permeameter consistent, so that the measured permeability coefficient is more accurate.
The invention provides a multi-connected flexible wall permeameter, which comprises a bracket, wherein a transparent cylinder is arranged in the bracket, a top cover covers the upper end of the transparent cylinder, a bottom cover is arranged at the lower end of the transparent cylinder, the top cover and the bottom cover are both tensioned on the transparent cylinder body by adopting a bracket and are fixed, the bottom cover in the transparent cylinder body is provided with a base, a lower permeable stone is arranged on the base, a soil sample is arranged above the lower permeable stone, an upper permeable stone is arranged above the soil sample, a top seat is arranged above the upper permeable stone, the peripheries of the base, the lower permeable stone, the soil sample, the upper permeable stone and the top seat are jointly wrapped with rubber membranes, the penetrating fluid conveying device is communicated with one end of the soil sample through a liquid inlet pipe, the shower fluid collecting bottle is communicated with the other end of the soil sample through a liquid outlet pipe, the inner cavity of the transparent cylinder body is connected with a water inlet pipe and a water outlet pipe, and the upper end and the lower end of the soil sample are connected with exhaust pipes; the pressure reducing device is characterized in that a pressure reducing channel is arranged on the top cover, a pressure reducing valve is configured in the pressure reducing channel, the pressurizing branch pipes are communicated with the inside of the transparent cylinder body through the top cover, a check valve is arranged on each pressurizing branch pipe, a plurality of flexible wall permeameters are configured, each pressurizing branch pipe of each flexible wall permeameter is connected with a pressurizing main pipe in a guide mode, and each pressurizing main pipe is connected with a pressurizing pump.
The invention has the technical effects that: 1. a single pressure pump supplies air pressure to a plurality of flexible wall permeameter branch pipes through a main pipe, so that the using amount of the air pump is saved, and the workload of operators is reduced; 2. because an air pump provides air pressure for each flexible wall permeameter, the air pressure in each flexible wall permeameter can be kept strictly consistent, and when the permeability coefficients of a plurality of samples under the same environmental conditions need to be manufactured and tested, more accurate permeability coefficient data can be obtained after the air pressure of each flexible wall permeameter is kept strictly consistent.
Drawings
Fig. 1 is a schematic structural diagram of a first embodiment of a multi-connected flexible wall permeameter provided by the invention.
Fig. 2 is a schematic structural diagram of a second embodiment of the multi-connected flexible wall permeameter provided by the invention.
Detailed Description
Referring to fig. 1, a multi-connected flexible wall permeameter according to a first embodiment of the present invention includes a support 1, a transparent cylinder 2 is disposed in the support 1, a top cap 3 covers an upper end of the transparent cylinder 2, a bottom cap 4 is disposed at a lower end of the transparent cylinder 2, the top cap 3 and the bottom cap 4 are both tightened on the transparent cylinder 2 by the support 1 and fixed, a base 5 is disposed on the bottom cap 4 in the transparent cylinder 2, a lower permeable stone 6 is disposed on the base 5, a soil sample 7 is disposed above the lower permeable stone 6, an upper permeable stone 8 is disposed above the soil sample 7, a top seat 9 is disposed above the upper permeable stone 8, rubber membranes 10 are wrapped around the base 5, the lower permeable stone 6, the soil sample 7, the upper permeable stone 8 and the top seat 9, a permeate fluid conveying device is communicated with one end of the soil sample 7 through a liquid inlet pipe 11, the permeate conveying device includes a permeate, a penetrating fluid is filled in the penetrating fluid bottle 12, the penetrating fluid bottle 12 is higher than the soil sample 7, the shower fluid collecting bottle 13 is communicated with the other end of the soil sample 7 through a liquid discharge pipe 14, the inner cavity of the transparent cylinder 2 is connected with a water inlet pipe and a water discharge pipe 15, and the upper end and the lower end of the soil sample 7 are connected with exhaust pipes 16; the top cover 3 is provided with a pressure reducing channel 17, the pressure reducing channel 17 is provided with a pressure reducing valve 18, the pressure branch pipes 19 are communicated with the inside of the transparent cylinder 2 through the top cover 3, the pressure branch pipes 19 are provided with one-way valves, the flexible wall permeameter is provided with a plurality of flexible wall permeameters, each flexible wall permeameter pressure branch pipe 19 is connected with a pressure main pipe 20 in a leading way, and the pressure main pipe 20 is connected with a pressure pump 21. Generally, 10 left and right flexible wall permeameters can be connected in a multi-connection mode, and the specific connection number can be adjusted according to actual needs.
Referring to fig. 1, in order to enable the air pressure in the transparent cylinder of each flexible wall permeameter to be adjusted individually and automatically, a pressure sensor is arranged in the transparent cylinder 2, an electromagnetic valve 22 is arranged on the pressurizing branch pipe, an electric actuator is arranged on the electromagnetic valve 22, and the pressure sensor and the electric actuator are connected with a PLC. The operator can input the air pressure value of each flexible wall permeameter to the PLC to automatically regulate and control the air pressure value.
Referring to fig. 2, the second embodiment of the present invention is substantially the same as the first embodiment except that: the transparent cylinder 2 is internally provided with a vertical sleeve 24, the top seat 9 is positioned in the vertical sleeve 24 and is slidably matched with the side wall of the vertical sleeve 24, the matching part of the vertical sleeve 24 and the top seat 9 is in liquid seal, the cavity in the transparent cylinder 2 is divided into a vertical pressure applying cavity 25 and a horizontal pressure applying cavity 26 by the vertical sleeve 24 and the top seat 9, and the vertical pressure applying cavity 25 and the horizontal pressure applying cavity 26 are respectively provided with a set of pressure reducing channel with a pressure reducing valve, a pressure branch pipe with a one-way valve and a pressure pump 21. The lower end of the inner wall of the vertical sleeve is provided with an annular convex edge which blocks the top seat to prevent the top seat from falling off the vertical sleeve; the outer side surface of the top seat 9 is provided with a sealing ring 27, the sealing ring 27 is closely matched with the inner wall of the vertical sleeve 24, and the sealing ring 27 can ensure that the top seat 9 keeps sealing when sliding downwards relative to the vertical sleeve 24. The transparent cylinder 2 of the flexible permeameter is divided into a vertical pressure application cavity 25 and a horizontal pressure application cavity 26 by a vertical sleeve 24 and a top seat 9, vertical and horizontal soil stress in a soil layer can be simulated, the vertical soil stress and the horizontal soil stress are generally regarded as the same in the traditional flexible wall permeameter, but the vertical soil stress and the horizontal soil stress are different all the time in the actual soil layer, so that the accuracy of the permeability coefficient test of a soil sample is reduced, and after the horizontal soil stress and the vertical soil stress are simulated respectively by the horizontal pressure application cavity 26 and the vertical pressure application cavity 25 successfully, the problem is solved well, and the permeability coefficient test data of the soil sample is more accurate.