Analysis Of Mechanical Behavior For Plastic Lining Members Of Plastic-concrete Underground Granary Under Water Pressure

The use of underground granary for grain storage can make the grain in a low-temperature closed environment,slow down the decay of food and maintain the quality.However,since the underground granary is built below the surface,it is susceptible to groundwater,and the problem of waterproof and moisture-proof is outstanding.The plastic-concrete composite waterproofing system studied in this project is a new structural system that uses the combination of plastic plates and concrete to waterproof the underground granary.The waterproof form is to connect the plastic plates with plastic studs and concrete pouring to form a waterproof layer of the underground granary.The waterproofing method can change the problem that the coil material and the paint are easy to fall off and damage in the outer waterproofing,overcome the shortcomings of the steel plate and the corrosion resistance,and is a new environmentally friendly waterproof form,which can ensure the long-term safe storage of the grain.The plastic-concrete composite waterproofing system consists of a waterproof plastic plate,a plastic stud,and a plastic connecting node.When the external water enters between the concrete and the waterproof plastic plate,the lining plastic member are endured water pressure.In this paper,through the combination of experiment and finite element analysis,the stress of various parts of the lining plastic components under water pressure is studied.The main contents and results are as follows:(1)Combined with the research status of plastic-concrete composite waterproofing system,the lining plastic components are summarized and designed.The plastic stud in the component adopts surface groove treatment to increase the pullout resistance of the concrete;the connection between the plastic stud and the waterproof plastic plate selects the threaded connection-welding combination node.According to the hydraulic test specimen model,the thickness of the waterproof plastic plate is selected to be 10 mm,and the spacing of the studs in the component is set to 200 mm,300mm and 400 mm.(2)The design and manufacture of the test specimens were carried out,and three hydraulic test members were fabricated according to different peg spacings,and the plastic members were processed and welded,and the test members were poured and cured.The strain measuring points are arranged at the key stress points inside the lining plastic component,and the displacement measuring points are arranged outside the test piece to study the plastic lining plastic parts in the plastic-concrete composite waterproofing system under different water pressure and different stud spacing conditions.Force and displacement changes.(3)The water-pressure loading test was carried out on the plastic-concrete composite waterproof test piece,and the strain and displacement under the action of water pressure were collected,and the phenomena and results during the test loading process were recorded.The test data was processed,and the failure mode and mechanism of the test piece were analyzed.It was concluded that the joint strength in the lining plastic component is the key to affect the hydraulic bearing capacity of the plastic-concrete composite waterproof test piece.The larger the test piece,the smaller the water bearing capacity.(4)The ABAQUS finite element analysis software was used to model and analyze the lining plastic components.Three different analysis methods of stud spacing were established according to the test components,and the hydraulic loading process was simulated to analyze the force and displacement changes in the components.By comparing and analyzing the test results,it is concluded that under the action of water pressure,the stress of the joint position and the stud is larger,and the positional stress of the waterproof plastic plate is smaller.As the spacing of the studs of the member increases,the joint The stress is also greater.The mid-span displacement of the plastic waterproof board outside the component increases linearly with the increase of water pressure,and the displacement at the node changes little.