| The quality of grouting engineering has urgent influence on the permeability and stability of dam, which is determined by the parameters applied in the grouting procedure. Real-time test of grouting parameters is the best way for quality control. The goal of the research is to study a set of auto-monitoring and recording system with excellent quality and multi-functions.The author has studied the problems existed in the popular-used grouting auto-recorder including the accurate testing of flow and water/cement ratio, the life span of micro-printer and in-situ grouting data arrangement as well. Based on the results, a set of new grouting auto recorder was designed and produced, after theoretical analysis and field test, the author made the following conclusions:1. Present the macro cycle grouting plan, resolve the flow testing problem of the cycle grouting. Because the past auto-recorder has only one flow-meter, constructers has to grout with the so called Minor Cycle Grouting Method (MCGM), which has huge influence on the grout properties and strength of the coagulum, sometimes even results in drilling accident. The author presented a new design of grout auto-recorder, which can test the flow of cycle grouting, i.e. mounting flow-meters on both input-pipe and output-pipe. The real flow into the grout hole equals: QR = QIN - Qour2. The source and channels of interference on the electro-magnetic flow-meter in field were founded, and methods of interference-control were presented. There are three kinds of interference on the electro-magnetic flow-meter in field, i.e. (1) the wave of grouting pressure and (2) interference between entering and returning flow-meters because their signals go into the main board through two analogue ports of the same CPU, and (3) interference caused by powerful equipments such as motors and distribution box. Based on the theoretical analysis and field test, the following experiences of interference-control were obtained, i.e. (1) write programs to modify the interference based on the changing rules of entering and returning flow during adjusting the grout pressure,vand (2) using isolation method to transfer signals between entering or returning electro-magnetic flow-meters and CPU, and (3) mounting flow-meters faraway from motors and distribution box, keeping space between two entering and returning flow-meters, and (4) Flow-meters should be full-filled with grout when grouting. Electrodes should keep clear after stopping grouting each time, and (5) ensure good earth connection of the flow-meters.3. The pressure transistor should be used together with the oil-water isolator, which can avoid corroding because of direct contact of the film with grout.4. Apply the nucleus density transistor to test water-cement ratio for the first time. This kind of transistor has many advantages such as real-time test without contact, high accurate and sensitivity (commonly 0.003g/cm3) and broad test range etc., which is suitable for engineering construction field.5. Design a thermal line printer for grouting engineering, which has advanced thermal printer head, long life span and light maintenance. The printer is suitable for engineering construction field with heavy dust, high moist or temperature.6. Design data memory which can simplify the data processing procedure obviously. The data memory designed for the autoreeorder can hold on-line initial grouting data automatically and put data into computer through a normal serial interface. Data in the computer can be processed by the special grouting management software and be transferred into varies of figures and tables set by standards. The design is the first one in the field of grout auto-recorder7. The LJ-Grout Auto Recorder System is the first product in similar products in China which can test real-time pressure, flow and water-cement ratio of the grout.
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