The Research On Automatic Monitoring And Intelligent Decision System Of Foundation Pit Dewatering In Coastal Area

The coastal area has a high groundwater level and a strong permeable stratum.Affected by the climate,rainwater is abundant.The groundwater level of foundation pits changes frequently and varies greatly.During the excavation of large ship lock foundation pits,the precipitation requirements are high and the ship lock construction period is long.The dewatering energy consumption of the foundation pit is huge.How to ensure the effectiveness of water drop in the foundation pit of the ship lock under changing groundwater conditions and to save energy to the greatest extent is a topic worthy of in-depth study.Based on this,this article takes the intelligent precipitation of the foundation pit ship lock as the starting point to carry out a series of model research and system development.The main research contents and results are as follows:1)Based on the theory of groundwater well flow movement,a three-dimensional groundwater model of the Babao ship lock foundation pit is established.The simulation results show that the model water level results have a good fit with the field measured water level results,which proves the accuracy of the model.Then,based on the threedimensional groundwater model of the foundation pit,the simulation calculations of the three working conditions of strong tide,heavy rainfall,and well point failure were carried out.The simulation results show that heavy rainfall and well point failure would bring greater threats to the ship lock foundation pit than a strong tide surge.Big threat.Subsequently,the calculation of the above three working conditions combination was carried out,and the simulation results showed that no matter the combination of the two working conditions has a greater threat to the foundation pit,it is necessary to take measures in advance when encountering the combination of two unfavorable working conditions during construction.Ensure the safety of foundation pit construction.2)Based on the rapid changes in water levels in coastal areas,traditional manual measurement cannot meet the requirements of water level measurement.A set of automatic monitoring equipment for foundation pits has been developed to monitor the water level of foundation pits and pump flow.The flow sensor realizes the control of the whole system by embedding Python code in the microcomputer.The automatic monitoring equipment is installed in the Babao ship lock foundation pit after indoor debugging,and transmits a set of water level flow data to the cloud server in 5 minutes,and the PC or mobile phone can display the cloud data to users in real time.After several months of operation and debugging,the stability and reliability of the automatic monitoring equipment have been confirmed.3)Based on the concept of safety in foundation pit construction and energy saving and emission reduction,a set of intelligent decision-making system for foundation pit pumps has been developed.This system is based on the automatic monitoring equipment framework and adds three kinds of equipment: frequency converter,variable frequency pump and relay,so that the water pump Intelligent control becomes possible.The intelligent decision-making system has designed two sets of schemes.Scheme one uses a relay as the control end of the water pump.The relay circuit is controlled by a microcomputer to realize the on-off control of the water pump.The equipment is simple and the program is simple,but it can only control the start or stop of the water pump.The second scheme uses the frequency converter as the water pump control end,and the microcomputer controls the frequency converter to realize the multi-frequency adjustment of the frequency conversion water pump.Simultaneously,the idea of reservoir capacity adjustment is introduced,and the water level of the foundation pit is intelligently pre-adjusted through the program,so as to realize the safe precipitation of the foundation pit while taking into account the minimum consumption of energy.Subsequently,an automatic alarm program was written for the system.In the case of abnormal water levels and the system cannot handle them,it can be reported to the administrator by email for manual intervention to ensure the safety of the project.