Study On Rapid Construction Technology Of Bridge Using 3D Printing Concrete

At present,the additive manufacturing 3D-print-concrete(3DPC)construction technology is developing rapidly,and it has fully proved its advantage of labour-saving,time-saving,and rapid erection.The 3D-print rapid-erection technology is very potential in bridge prefabrication.At present,90% of highway bridges with a span less than 50 metres have used highly standardized prefabricated girders,and the girder construction period is usually up to 60 days.If 3DPC technology can be applied in the process of prefabrication,there will be benefit of formwork-free,labour-saving,less construction period,and the site using cycle will be greatly reduced,and there will be economic benefits in large scale.The project which this thesis based on,Shanghai wisdom bay Bridge,is a masonry arch bridge built with 3D printing pieces,with a span of 14.4meters,and it can be served as a preliminary study of 3D printing rapid construction technology.This thesis combined the 3D printed concrete material characteristics to study the key technologies of the bridge’s modular design and fabricated construction,and combined with scale experiments,health monitoring,and numerical analysis.Methods The mechanical behavior of the bridge was studied.Combining the cutting-edge new technology of 3D printing with modular design and assembly construction for rapid bridge construction has great research significance and necessity.In the next ten years,3D printing technology will have unprecedented development.As the cost of technology development decreases,this construction method managed by computer programs will be more widely used to promote the digitalization,industrialization and modularization of construction projects And unmanned development.This article is an exploratory study of this new technology,and has achieved certain results,and has a guiding role for similar engineering and technical research.Based on the 3D printed concrete material property test,the differences between the 3D printed concrete and the molded concrete in the failure mode are summarized.The experimental results show that the3 D printed concrete material properties are close to mortar and the elastic modulus is low;The compressive strength is relatively close to the transverse compressive strength.It can be regarded as an isotropic material during calculation.The 3D printed concrete extrusion width has little effect on the material strength.The 3D printed concrete has no obvious volume nonlinear effect.It is printed in a humid environment.The mechanical index of concrete is better than that of concrete materials printed in dry environment.A series of 3D printed concrete bridge modular design and assembly construction techniques are summarized through the demonstration project of the Smart Bay.The technology mainly includes the three important links of modular design: splitting,connecting node design,lifting and connection step planning.The bridge is split into standardized parts that can be mass-produced,so that it can be batch-completed in the factory using a 3D printer.A three-dimensional model is created for each module,and the walking path of the 3D printed robotic arm is designed.A computer program is used to Controls the prefabrication of each module.After the concrete is equipped and the equipment is commissioned,all the factory prefabrication work is completely completed by 3D printing machinery and equipment.In the prefabrication production process,the embedded parts of the connection nodes are built in the prefabricated parts,so that the on-site lifting and splicing work can be carried out in an orderly and coherent manner.In the application of 3D printed pedestrian bridges in Smart Bay,this technology fully reflects the advanced nature of rapid construction of bridges,de-manufacturing,and simplified construction management.It fully realizes the industrialization of construction projects and the digitization of construction projects.It is widely used in bridge engineering.