各监测仪器的观测频率如下：（1）真空度监测：真空预压开始后，泵上及膜下

The observation frequency of each monitoring instrument is as follows: <br>(1) Vacuum degree monitoring: after the vacuum preload starts, the vacuum degree on the pump and under the membrane is measured every 2 hours. If the vacuum pressure drops, you should immediately find the cause and deal with it in time. Once a day after stabilization. <br>(2) Observation of surface settlement: The position of the settlement mark should correspond to before and after the film laying. Observe once a day for 30 days before evacuation, every 2 days for 30 to 50 days, every 4 days after 50 to 80 days, and every 5 days after 80 days. Increase the observation frequency in case of special circumstances. <br>(3) The pore water pressure is observed once before pumping, and the pore water pressure is observed once every day during pumping. <br>(4) Layered settlement observation: same as the observation frequency of surface settlement.

The observation frequencies of the monitoring instruments are as follows:<br>(1) Vacuum monitoring: after the vacuum pre-pressure starts, the vacuum on the pump and under the membrane every 2 hours, found that the vacuum pressure has decreased phenomenon should be immediately found cause and timely treatment. Once a day after stabilization.<br>(2) Surface subsidence observation: the settlement mark position should be addressed before and after the film is laid. 30 days before the vacuum observation once a day, 30 to 50 days every 2 days, 50 to 80 days after every 4 days, 80 days after every 5 days. Increase the frequency of observations in case of special circumstances.<br>(3) Pore water pressure is observed once before pumping, and pore water pressure is observed once a day during pumping.<br>(4) Stratified settlement observation: the observation frequency of the same surface layer subsidence.

The observation frequency of each monitoring instrument is as follows:<br>(1) Vacuum degree monitoring: after the start of vacuum preloading, the vacuum degree on the pump and under the membrane shall be measured and read every 2 hours. If the vacuum pressure drops, the cause shall be found out immediately and handled in time. Once a day after stabilization.<br>(2) Surface settlement observation: the position of settlement mark shall be corresponding before and after membrane laying. Observe every day 30 days before vacuuming, every 2 days in 30-50 days, every 4 days in 50-80 days and every 5 days in 80 days. In case of special circumstances, increase the observation frequency.<br>(3) Pore water pressure is observed once before pumping, and once a day during pumping.<br>(4) Layered settlement observation: the same as the surface settlement observation frequency.