First, the pre-construction inspection before construction raw materials, machinery and equipment and jet technology and other checks, mainly in the following aspects:
Quality certification and re-inspection report ① raw materials (including cement, admixture, accelerator, suspensions and other additives), and mixing the identification results of water;
② slurry mix is appropriate engineering soil conditions;
③ mechanical equipment is normal, pre-construction to deal with high pressure jet grouting equipment, geological drilling rig, high-pressure mud pumps, water pumps and other machines for the test run, while ensuring that the drill pipe (especially multi-drill), drill and inducer of obstruction;
④ Check the injection process is suitable geological conditions in the pre-construction process should also make spray test, test spray in the original pile position spray test, test spray pile hole number not less than two-hole, if necessary, adjust the injection process parameters.
⑤ underground obstacles before construction should also be unified case investigation to ensure that drilling and injection to meet the design requirements.
⑥ pile pre-construction inspection, pressure gauges, flow meter accuracy and sensitivity.
Second, the construction of the check on the construction of the focus on checking the contents are:
① drill pipe and drill positioning verticality;
② cement slurry mix and materials weighing;
③ rig speed, heavy drilling speed, improve drilling speed and rotational speed;
④ jet grouting when spraying (water, jet) pressure grouting speed and grouting;
⑤ holes oozing slurry condition at;
⑥ nozzle sinking lap length and grouting pipe segment elevation during lifting;
⑦ construction records are complete, the construction should be a pressure and flow data recorded at each change to enhance the soil at the junction of 1m or records.