In this paper,the application strategy of ultrasonic detection technology in the detection of concrete foundation piles is analyzed using a construction project as an example.It includes a basic overview of the projec...In this paper,the application strategy of ultrasonic detection technology in the detection of concrete foundation piles is analyzed using a construction project as an example.It includes a basic overview of the project,an overview of ultrasonic testing technology in bridge concrete pile foundation testing,and an analysis of its practical application in the concrete pile foundation testing of this project.The objective of this analysis is to provide some reference for the application of ultrasonic testing technology and the improvement of the quality of bridge concrete pile foundation testing.展开更多
In this work, the rheological changes of several crude oil samples exposed to ultrasonic waves for different time intervals in addition to the effect of temperature on viscosity behavior of heavy crude oils were inves...In this work, the rheological changes of several crude oil samples exposed to ultrasonic waves for different time intervals in addition to the effect of temperature on viscosity behavior of heavy crude oils were investigated using a series of steady shear flow and oscillatory tests. The colloidal structural evolutions of flocs in oil samples were illustrated by analysis of the size distribution of flocculated asphaltene particles （confocal microscopy tests）. The rheological investigations indicate that the ultrasonic irradiation dissolved heavy components in crude oil. After ultrasonic treatment, the Kouh-e-Mond crude oil was found to be pseudoplastic. In addition, confocal microscopy confirms that there was an optimum duration for ultrasonic irradiation, at which the viscosity and flocculation rate of asphaltenic crude oils reduced to the minimum values. The optimum was found to be approximately 40 min for the Kouh-e-Mond crude oil. Experimental results illustrate that the ultrasonic irradiation could disaggregate heavy colloid components in crude oil, and breakdown of asphaltene molecules would only occur in a specific time interval of irradiation. Also according to the temperature sweep test, the oil temperature rise caused by ultrasonic irradiation was not the main reason for theological changes of the crude oil and this alteration may be due to physical and chemical phenomena induced by sonication in crude oil.展开更多
Ultrasonic vibration-assisted technology is widely utilized in the performance research and manufacturing process of metallic materials owing to its advantages of introducing highfrequency acoustic systems. However, t...Ultrasonic vibration-assisted technology is widely utilized in the performance research and manufacturing process of metallic materials owing to its advantages of introducing highfrequency acoustic systems. However, the acoustic plasticity constitutive model and potential mechanism, involving Ti3Al intermetallic compounds, have not yet been clarified. Therefore, the Ultrasonic-K-M hybrid acoustic constitutive model of Ti3Al was established by considering the stress superposition, acoustic thermal softening, acoustic softening and acoustic residual hardening effects according to the dislocation density evolution theory and crystal plasticity theory. Meanwhile, the mechanical behavior of ultrasonic vibration-assisted tension(UVAT) and microstructure of ultrasonic vibration-assisted milling(UVAM) for Ti3Al was investigated. Dislocation density to be overcome from initial deformation to failure of Ti3Al was calculated in UVAT and was verified in UVAM. The results indicated that the Ultrasonic-K-M model showed a good agreement with the experimental data. There was an obviously softening phenomenon after introducing the ultrasonic energy field in the Ti3Al whole deformation region, and the degree of softening was positively correlated with amplitude. Furthermore, the maximum reduction ratio in yield strength of Ti3Al was16 % and the maximum reduction value in ultimate tensile strength was 206.91 MPa. The elongation rose first and then fell as amplitude enlarged, but only as the vibration was applied in the whole deformation region, the elongation was always greater than 14.58 %. In addition, The UVAM process significantly reduced the dislocation density increment to be overcome for Ti3Al material removal by 1.37 times, and promoted dislocation motion and cancellation to make twisted dislocations evolve into parallel dislocations. As the amplitude increased to 4 μm, the depth of the disturbed area of the plastic deformation layer increased by a maximum of 2.5 times.展开更多
The measurement of pig backfat thickness(PBFT)has to stand up to challenges with the reliability,accuracy,and convenience.Acquiring PBFT timely and precisely from a finite distance is extremely necessary to improve th...The measurement of pig backfat thickness(PBFT)has to stand up to challenges with the reliability,accuracy,and convenience.Acquiring PBFT timely and precisely from a finite distance is extremely necessary to improve the process of pig production and implement effective management.In an attempt to alleviate these problems,an online handheld terminal was designed with a new method based on ultrasonic technology for measuring PBFT during the process of pig breeding,which can overcome the difficulties encountered in other destructive means.The terminal comprised three main components:a main microcontroller unit(MCU)to measure PBFT,a RFID module to identify each pig and send data(e.g.identity,measurement time and PBFT)to a server via wireless transmission module,and an ultrasonic transducer to drive and receive signals between them.A measurement error within 0-1 mm was acquired through testing three groups of samples.Results indicated that this handheld terminal had a required accuracy and proved that the ultrasonic wave processing method can be deployed in a mobile terminal for PBFT measurement.It also provided a feasible nondestructive alternative to measure PBFT.Associated with information management software platform,this method may ultimately help pig production farmers measure the PBFT accurately and conveniently,and improve the pig production efficiency.展开更多
文摘In this paper,the application strategy of ultrasonic detection technology in the detection of concrete foundation piles is analyzed using a construction project as an example.It includes a basic overview of the project,an overview of ultrasonic testing technology in bridge concrete pile foundation testing,and an analysis of its practical application in the concrete pile foundation testing of this project.The objective of this analysis is to provide some reference for the application of ultrasonic testing technology and the improvement of the quality of bridge concrete pile foundation testing.
文摘In this work, the rheological changes of several crude oil samples exposed to ultrasonic waves for different time intervals in addition to the effect of temperature on viscosity behavior of heavy crude oils were investigated using a series of steady shear flow and oscillatory tests. The colloidal structural evolutions of flocs in oil samples were illustrated by analysis of the size distribution of flocculated asphaltene particles （confocal microscopy tests）. The rheological investigations indicate that the ultrasonic irradiation dissolved heavy components in crude oil. After ultrasonic treatment, the Kouh-e-Mond crude oil was found to be pseudoplastic. In addition, confocal microscopy confirms that there was an optimum duration for ultrasonic irradiation, at which the viscosity and flocculation rate of asphaltenic crude oils reduced to the minimum values. The optimum was found to be approximately 40 min for the Kouh-e-Mond crude oil. Experimental results illustrate that the ultrasonic irradiation could disaggregate heavy colloid components in crude oil, and breakdown of asphaltene molecules would only occur in a specific time interval of irradiation. Also according to the temperature sweep test, the oil temperature rise caused by ultrasonic irradiation was not the main reason for theological changes of the crude oil and this alteration may be due to physical and chemical phenomena induced by sonication in crude oil.
基金supported by the National Natural Science Foundation of China(Nos.51875179 and 52275419).
文摘Ultrasonic vibration-assisted technology is widely utilized in the performance research and manufacturing process of metallic materials owing to its advantages of introducing highfrequency acoustic systems. However, the acoustic plasticity constitutive model and potential mechanism, involving Ti3Al intermetallic compounds, have not yet been clarified. Therefore, the Ultrasonic-K-M hybrid acoustic constitutive model of Ti3Al was established by considering the stress superposition, acoustic thermal softening, acoustic softening and acoustic residual hardening effects according to the dislocation density evolution theory and crystal plasticity theory. Meanwhile, the mechanical behavior of ultrasonic vibration-assisted tension(UVAT) and microstructure of ultrasonic vibration-assisted milling(UVAM) for Ti3Al was investigated. Dislocation density to be overcome from initial deformation to failure of Ti3Al was calculated in UVAT and was verified in UVAM. The results indicated that the Ultrasonic-K-M model showed a good agreement with the experimental data. There was an obviously softening phenomenon after introducing the ultrasonic energy field in the Ti3Al whole deformation region, and the degree of softening was positively correlated with amplitude. Furthermore, the maximum reduction ratio in yield strength of Ti3Al was16 % and the maximum reduction value in ultimate tensile strength was 206.91 MPa. The elongation rose first and then fell as amplitude enlarged, but only as the vibration was applied in the whole deformation region, the elongation was always greater than 14.58 %. In addition, The UVAM process significantly reduced the dislocation density increment to be overcome for Ti3Al material removal by 1.37 times, and promoted dislocation motion and cancellation to make twisted dislocations evolve into parallel dislocations. As the amplitude increased to 4 μm, the depth of the disturbed area of the plastic deformation layer increased by a maximum of 2.5 times.
基金supported by Project of Science Operating Expenses from Ministry of Education of China(Grant No.2017PT19)Chinese Universities Scientific Fund(Grant No.2017XD003).
文摘The measurement of pig backfat thickness(PBFT)has to stand up to challenges with the reliability,accuracy,and convenience.Acquiring PBFT timely and precisely from a finite distance is extremely necessary to improve the process of pig production and implement effective management.In an attempt to alleviate these problems,an online handheld terminal was designed with a new method based on ultrasonic technology for measuring PBFT during the process of pig breeding,which can overcome the difficulties encountered in other destructive means.The terminal comprised three main components:a main microcontroller unit(MCU)to measure PBFT,a RFID module to identify each pig and send data(e.g.identity,measurement time and PBFT)to a server via wireless transmission module,and an ultrasonic transducer to drive and receive signals between them.A measurement error within 0-1 mm was acquired through testing three groups of samples.Results indicated that this handheld terminal had a required accuracy and proved that the ultrasonic wave processing method can be deployed in a mobile terminal for PBFT measurement.It also provided a feasible nondestructive alternative to measure PBFT.Associated with information management software platform,this method may ultimately help pig production farmers measure the PBFT accurately and conveniently,and improve the pig production efficiency.
