Research On Damaged RC Beam Repaired With Intelligent Shape Memory Alloy Based On Arduino UNO

Most of the traditional civil design,construction and post-repair and reinforcement require human on-site participation,which has problems such as prolonged construction period,low efficiency and safety guarantee.With the advent of the era of intelligence,emerging technologies such as smart materials and computer technology are used to empower the traditional infrastructure industry to achieve intelligent design,construction,repair and reinforcement of structures.In order to achieve the application of intelligence in civil engineering,this paper uses the shape memory effect of the new intelligent material shape memory alloy to explore and design its supporting intelligent control hardware and software facilities,and is committed to intelligent reinforcement of reinforced concrete beams,and repair of reinforced concrete beams after damage.The main research work of this paper is as follows:(1)In this paper,the related material properties of CFRP,epoxy resin and SMA wire were studied.The experiment is divided into two parts: Part I: the material properties test of the material required for compounding with SMA wire,mainly the uniaxial tensile test of CFRP sheet and the uniaxial tensile test of epoxy resin bone rod,respectively obtained their uniaxial tensile strength and elastic modulus;Part II: Research on basic thermodynamic properties of SMA wire,including: a)uniaxial tensile experiments of SMA wire in martensite phase,b)SMA wire experiments on the relationship between the temperature of the SMA wire and the energization current,c)the recovery stress experiment that the SMA wire can produce under different pre-strains,and d)the effect of the cyclic heating and cooling of the SMA wire on the recovery force that the SMA wire can produce experiment.The experiment obtained the corresponding relationship between the temperature and the current of the SMA wire;according to the recovery performance test,the recovery stress-temperature relationship of the SMA wire was obtained;and the recovery force can be stabilized by repeated heating and cooling training of SMA wire.(2)Based on the research on the material properties of SMA wire,this paper explores and designs an intelligent control device for SMA wire from the perspective of software and hardware.For hardware research and development,this experiment uses the Arduino UNO intelligent development board as the intelligent control terminal,designs and manufactures the strain sensor module and the relay module,and supplies them with the required power supplies.Finally,use the breadboard and wires to connect all the hardware and SMA wires The hardware is connected to form a complete loop intelligent control system;for software research and development,this paper mainly compiles the program logic with the Arduino IDE software matched with the Arduino UNO intelligent development board,and assists in the secondary development with Python and Jupyter Notebook to realize the real-time visualization and realtime storage of data.The logic of the entire control program is written in C language and Python language,based on the characteristics of SMA’s heating to generate restoring force,and combined with the PWM principle to intelligently control the output voltage.The software is checked,and finally the function of intelligent output current of SMA wire can be realized according to the external conditions.(3)In this paper,the SMA wire and FRP are compounded and attached to the bottom of the reinforced concrete beam,and the intelligent control device developed by the research and development is connected,and then the load is applied to the reinforced concrete beam to explore the realization effect of the device in the actual reinforced concrete beam loading experiment.Observe the changes of beam bearing displacement,loading point displacement,mid span displacement,mid span strain and crack width of the beam.The experiment found that the intelligent control device developed in this paper can repair the beam for many times,and the repair ability of SMA wire will not be significantly reduced after the beam is damaged for many times.There is no human participation in the whole process of beam restoration,thus achieving true intelligence.