| With the rapid development of China’s construction industry,problems such as rising labor costs,waste of resources and environmental pollution come one after another.The traditional cast-in-situ construction method has been overwhelmed.The prefabricated construction method has the advantages of reducing labor,low consumables,reducing pollution and increasing efficiency,convenient construction and so on.The 19 th National Congress of the Communist Party of China proposed that the development of prefabricated construction is a new direction of China’s construction industry reform and an important driver of the transformation and upgrading of the construction industry.In this new situation,the development of prefabricated buildings in China is not plain sailing.The high construction cost is the key factor restricting the development of prefabricated buildings in China.The reduction of construction cost is inseparable from scientific and reasonable cost control and cost prediction.Therefore,in order to implement the development goal of transformation and upgrading of the construction industry,starting with the key factors affecting the cost of prefabricated buildings,this paper establishes the cost prediction model of prefabricated buildings,and puts forward the corresponding cost control suggestions.By combing the literature of prefabricated buildings at home and abroad,considering the principle of index selection and the characteristics of prefabricated buildings,this paper identifies 18 factors affecting the cost of prefabricated buildings from four aspects: project characteristics,production design,component transportation and assembly construction.Then the Analytic Hierarchy Process（AHP）and Entropy Weight Method（EWM）are used to comprehensively weight the cost influencing factors,and 16 main factors are selected,so as to construct the prefabricated construction cost prediction index system;After analyzing and comparing the common prediction models,Back Propagation Neural Network（BPNN）with strong generalization ability and high precision is selected as the prediction model,and Quantum Particle Swarm Optimization（QPSO）is introduced to determine the best structure of BPNN,and the prediction model based on QPSO-BP neural network is established;Finally,the applicability of the model is verified by the historical data of prefabricated construction engineering,and BPNN and PSO-BP neural network are constructed for comparative analysis to verify the superiority of QPSO-BP model.The results show that QPSO-BP cost prediction model has faster convergence speed and higher prediction accuracy.Its prediction accuracy is as high as99.21% and the average prediction error rate is only 2.19%.It is a more applicable assembled construction cost prediction model.Finally,based on the research results,the following cost control suggestions are put forward from the production design dimension,component transportation dimension and assembly construction dimension of prefabricated buildings: on the premise of ensuring the quality of prefabricated buildings,the prefabrication rate of buildings should be reasonably improved and the large-scale effect should be accelerated.Standardizing the design standards of components and reducing the degree of component alienation.Promote the informatization development of architectural design and deepen the application of BIM Technology in the design stage;In order to reduce the transportation cost of components,the component factory nearest to the construction site shall be selected for cooperation,and the road conditions for component transportation shall be explored in advance.When loading components,the vehicle loading space shall be reasonably used to improve the transportation efficiency.The components shall be stacked and installed in strict accordance with the construction design sequence to reduce the storage cost of components;Strengthen the training of workers,improve the construction specialization level of workers,strengthen the coordination between departments,improve the incentive mechanism for workers,and mobilize the enthusiasm of workers.Carry out scientific construction planning and select cost-effective mechanical equipment to ensure the reasonable layout of construction machinery.Figure [8] table [16] reference [88]... |
