Research On Quality Tracing And Management Of Prefabricated Steel Structure Residence

Prefabricated steel structure residence has been vigorously promoted in recent years because of its advantages of high construction efficiency,low environmental pollution and energy conservation and emission reduction.In the construction process of fabricated steel structure residential project,a series of quality defects such as component deformation,installation dislocation,welding undercut,coating moisture and so on are easy to appear.Analyzing the causes and influencing factors of quality defects can effectively control the occurrence of quality defects.However,at present,our analysis of the causes of quality defects mainly depends on expert experience,which has many manpower investment,long time-consuming and low accuracy.In view of the above problems,based on the full analysis of the factors affecting the quality of prefabricated steel structure housing,this paper puts forward the case-based reasoning method of quality traceability,which can quickly determine the cause of defects when quality defects occur.The main research contents of this paper are as follows:Firstly,the factors influencing the quality of prefabricated steel structure residence are analyzed.The common quality defects and their causes are analyzed from the six stages of architectural design,component production,transportation yard,component hoisting,component connection and component coating.The factors affecting the quality of prefabricated steel structure housing are preliminarily identified,and the factor system affecting the quality of prefabricated steel structure housing is constructed.The system includes 37 influencing factors,such as low degree of design informatization,non-standard operation of production personnel,and unqualified quality of connecting materials.By constructing the interpretive structure model,this paper analyzes the hierarchical structure and interaction of the factors affecting the quality of prefabricated steel structure housing,and puts forward some management and control suggestions.Secondly,through literature research,the content of quality defect case information of fabricated steel structure residence is determined,including four types of case information: building information,process information,element participation information and construction result information.Taking the welding defect of steel member as an example,15 pieces of information for defect recording are explained.The frame representation method is used to represent the quality defect case information of fabricated steel structure residence,and the specific content of the case information is discretized and recorded.Based on the field investigation of two prefabricated steel structure residential projects under construction in Beijing,a total of87 quality defect cases are collected,and the quality defect case database of prefabricated steel structure residential buildings in this paper is established.Finally,a case-based reasoning method for tracing the causes of quality defects of fabricated steel structure housing is proposed.The tracing method adopts the nearest neighbor search method as the similarity matching algorithm of quality defect case information,in which the genetic algorithm is used to determine the weight of various case information in the similarity calculation.Through similarity matching,the traceability method can retrieve the existing defect cases similar to the new quality defects from the quality defect case base,further analyze the defect causes of the similar existing defect cases,and infer the causes of the new quality defects.This paper randomly selects a case from the quality defect case database as the verification case and the remaining cases as the retrieval case.The defect causes of the verification cases inferred by the Traceability Method in this paper are consistent with their actual causes,which proves the correctness and applicability of the Traceability Method in this paper.Combined with the hierarchical structure diagram of factors affecting the quality of prefabricated steel structure housing constructed in this paper,this paper puts forward targeted control strategies for the verification cases.