Corrosion is one of the main causes of damage and leakage in oil and gas pipelines,and accurately predicting the corrosion rate is crucial for pipeline safety.This study established a model based on the Sparrow Search Algorithm(SSA)-optimized Light GBM to predict the average corrosion rate of oil and gas pipelines.Meanwhile,the study employed the Synthetic Data Augmentation(SDA)technique to expand the dataset,enhancing the accuracy and stability of the model;and evaluated the model performance through comparative analysis.In the study,the Sparrow Search Algorithm(SSA)was first used to optimize the parameters of the LightGBM model,forming the SSA-LightGBM model.This model was then used to train and predict the corrosion rate of oil and gas pipelines,and the error and stability of the prediction results were analyzed.The results show that the SSA-LightGBM model has high accuracy and stability in predicting the average corrosion rate of oil and gas pipelines.In addition,the prediction results of the SSA-LightGBM model were compared with those of other models such as LightGBM,GBRT,CatBoost,SSA-GBRT,and SSA-CatBoost.The results indicate that the SSA-LightGBM model performs best in terms of accuracy and stability.
In recent years,global warming has led to an increase in extreme weather&climate events.Many cities have formulated systematic plans for waterlogging control in accordance with relevant documents.However,due to insufficient coordination with external systems in planning&design,the system lacks the guidance.From the three levels of upper planning,special planning and construction plan,it studies the connecting points between the systematic implementation plan of waterlogging control,related planning&design.Through the overall planning&feedback of population,land use,coordinate system,blue&green space,flood control&drainage,vertical elevation,sponge city,underground tunnel,co-treatment of rain&pollution,and timely scheduling of construction projects,etc.To realize the transmission&landing of the upper planning,the coordination of the special planning system&the consolidation of the construction plan,so as to avoid the possible contradictions&conflicts with the existing planning&design in different lines,strengthen the connection of relevant majors&projects,and improve the work efficiency,systematicness,scientificity&implementability of the implementation plan.
The reinforcement of underground structures is mostly controlled based on crack width.It analyzes the changes in economic reinforcement of underground structures under different steel bar spacing,internal force size,&material price conditions by enumerating within a certain range.The results indicate that there is not much difference between the economic reinforcement ratios based on crack control&strength control,but the variation patterns are not consistent.The structural cost will decrease with an increase in structural reinforcement ratio and a decrease in component size,especially when the unit price of concrete is high.The economic reinforcement ratio of the structure will approach or even exceed the maximum reinforcement ratio.When only considering the main reinforcement,a high reinforcement ratio can reduce the structural cost by 7.6%.Through simple examples,it is verified that the reinforcement scheme can reduce the overall cost of the structure by 15%.
With the gradual aging of urban population in recent years,the humanistic concept of people's cities for the people has been increasingly valued by departments at all levels.The improvement of pedestrian bridges in terms of convenience&comfort has become an urgent need for construction&improvement.Taking Yan'an Road Jiangsu Road Pedestrian Bridge Improvement Project in Shanghai as the starting point,combined with the travel needs of surrounding communities,it studies the aging adaptation strategy,and expounds some experiences and methods in the improvement of municipal building facilities from the perspective of barrier-free transformation and architectural landscape improvement.While improving the renovation of the project's age-appropriate function,it also provides a new idea for the age-appropriate transformation of other municipal building facilities to some extent.
Based on the in-situ suspension protection project of a large-diameter sewage pipeline crossing the auxiliary foundation pit at a station in Kunming Rail Transit L2 Phase II,a pipeline in-situ suspension protection system of concrete beam support+support hanger+vertical suspension rod+crossbeam is established,and a 3D numerical model of the suspension protection system is established using numerical simulation methods.At the same time,considering the influence of factors such as beam steel type,support&hanger steel type,steel spacing,and steel grade,different suspension system schemes are proposed,and the stress&deformation laws of each component structure are calculated based on the proposed numerical model.The results show that the optimal solution is the in-situ pipeline suspension system with section steel grade Q235,beam type H200×204×12×12,support hanger&vertical boom type H100×100×6×8 and section steel spacing of 800 mm.The scheme has high reliability&reasonable economy,and the research results can provide guidance&reference for the subsequent research on in-situ protection technology of pipelines crossing foundation pits.
