Deterioration Assessment Of Aqueduct Service State Based On Fuzzy Comprehensive Evaluation Method

Service status assessment is an important part of aqueduct operation management.For aqueducts that have been in operation for many years,it is necessary to carry out timely service status assessment work in order to clarify the deterioration of the service status of the aqueduct,discover the unsafe factors in the aqueduct operation in time,and carry out repair or renewal and even reconstruction work to avoid the loss of people’s lives and property.This paper selects the aqueduct in Jingtaichuan Electric Power Lift Irrigation Area in Jingtai County,Gansu Province as the research object.In the early stage,through field investigation and experiment,the apparent condition,internal defects,and carbonization depth of the aqueduct were measured using thermal imaging cameras,ultrasonic detectors,and steel corrosion detectors.The service status of steel bars,the compressive strength of aqueduct concrete,etc.Based on the data obtained from field tests,infer the degree of deterioration of the aqueduct’s service status.Compare the experimental data of different aqueducts and explore the laws of various experimental data.The field test lays the foundation for the selection of indicators for the deterioration assessment of the aqueduct’s service condition.In order to evaluate the deterioration of the aqueduct’s service status,this paper adopts the fuzzy comprehensive evaluation method,selecting the three aspects of man-made,material,environment and load effect,risk-removing reinforcement,maintenance conditions,construction quality,structural design;admixtures,admixtures,aggregates,Steel,cement;carbonation,alkali-aggregate reaction,steel corrosion,chloride erosion,freeze-thaw damage,a total of 15 sub-indices,to establish an evaluation index system for the deterioration of the aqueduct in service.When determining the weight of each index,in order to make the determination of the weight more scientific and objective,the subjective and objective weighting method is combined,and the subjective and objective weights are calculated by the analytic hierarchy process and the entropy weight method,and then the multiplication rule is used to superimpose to obtain the final combined weight..After determining the membership degree of each index,the second-level fuzzy comprehensive evaluation method is used to comprehensively consider the impact of each index to obtain the final degradation evaluation level of the aqueduct in service.Introduce the idea of cloud theory and establish a cloud model of the deterioration of the aqueduct’s service state.The evaluation standard cloud is first constructed,and the membership degree cloud model is used to calculate the digital characteristics of each index cloud with the determined weight of each index,and then the comprehensive evaluation cloud is solved,and it is displayed using the Matlab simulation function.It shows the development trend of the deterioration of the aqueduct’s service state,makes a more accurate judgment of the degree of deterioration of the aqueduct’s service state,and visually displays the evaluation results to make it more convincing and scientific.The specific conclusions are as follows:(1)The measured data of the aqueduct in Jingdian Irrigation District shows that the lower part of the aqueduct is more eroded than the upper part and has greater strength loss.This is because the lower part is closer to the soil and is more susceptible to the erosion of salt ions in the soil and the freeze-thaw cycle.The service status of the bent frame relative to the tank body is poor.This is because the bent frame is not only subjected to the load of the upper tank body during operation,but also corroded by various environmental factors.The steel corrosion inspection found that the probability of steel corrosion of the second-stage Zonggan18# aqueduct(old)that has been in operation for 32 years has reached 50%,and certain measures need to be taken to alleviate it.(2)Through the establishment of the deterioration assessment model of the aqueduct service state,the fuzzy comprehensive evaluation of the 18# aqueduct(old)aqueduct in Jingdian Irrigation District is carried out,and the combined weight of the combination of the analytic hierarchy process and the entropy weight method is used to balance the influence of subjective and objective factors on the weight determination.Finally,the second-level fuzzy comprehensive evaluation is used to get the service state deterioration evaluation level of the18# aqueduct(old)in Jingdian Irrigation District to be Level II.(3)Using the cloud theory to evaluate the deterioration degree of the aqueduct’s service status,it is concluded that the service status of the 18# aqueduct(old)in Jingdian Irrigation District is Class II and is beginning to develop to Class III.Using the Matlab simulation function,the trend of the deterioration of the aqueduct’s service status can be visually displayed,and scientific suggestions can be provided for the aqueduct renewal project in Jingdian Irrigation District.