Search

In order to solve the problem in predicting and warning the response of an in-service long piled wharf when a ship berths to it, and to improve the efficiency of monitoring and assessing the structural damage of a long piled wharf, a three -dimensional finite element model of a long piled beam-slab wharf considering pile-soil interaction was established based on an example of a long piled wharf using Midas/GTS NX software. The structural failure mode of a long piled wharf when a ship is berthing was studied and the response surface parameters were determined. The response surface equations for the structural response of a long piled wharf was established. Goodness-of-fit test, F-test and t-test were carried out to verify the accuracy of the equations and the significance of various influencing factors on the response of different structures was also analyzed. Finally, the predicted results of the structural response of a long piled wharf were evaluated through error analysis. The results of the study can be useful for the response prediction of long piled wharf structures. [ABSTRACT FROM AUTHOR]

To investigate the influence of crack depth and position of concrete beams on the driving and receiving effect of piezoelectric ceramics, ABAQUS software was used to simulate the output signals of healthy concrete beam model under different excitation sources. To determine the optimal excitation frequency and optimize the characteristics of piezoelectric sheet of shape, size and thickness, the output signals of healthy concrete beam model and damaged concrete beam models with cracks in different depths and positions were simulated and analyzed. The piezoelectric wave test was carried out to monitor the damaged and healthy concrete beam models. The results show that the output signal strength and wavelet packet energy are decreased with the increasing of crack depth. The closer the distance between penetrating crack and transmitting sensor is, the stronger the signal displayed by the sensor at the receiving end is. On the contrary, the farther the distance is, the larger the signal attenuation becomes. [ABSTRACT FROM AUTHOR]

Damage detection technologies of high-piled wharf piles play an important role in the safe and long -term use progress. To identify and judge the location and degree of pile damage is beneficial for people to repair and reinforce high-piled wharf structures timely. Damage testing technologies of high-piled wharf piles are varied. In this paper, we briefly introduced the traditional pile foundation inspection methods and their limitations at first, and then clarified the methods based on dynamic damage detection and their development. Finally, the damage detection technologies of high-piled wharf piles are summarized and proposed. [ABSTRACT FROM AUTHOR]

Effect of pile-driving on adjacent construction has always been an important subject for engineering researches. According to the possible construction risk of the pile-driving reconstruction project of a wharf in Zhejiang, we analyzed the considering factors of the monitoring scheme, and studied the design vision and the legitimacy. The scheme creatively combines the PPT (Pore water Pressure Translator) and the 3 -way vibration velocity sensor in one hole, which saves the cost and time immensely. We also analyzed the monitoring data, ensured the safety of surrounding buildings. The design and application of this monitoring scheme can serve as reference for relative engineering projects. [ABSTRACT FROM AUTHOR]

In view of the fact that the resistance in front side of the foundation is not considered in the stability calculation of the gravity anchor structure in the current code, it is necessary to combine the model test and finite element analysis, obtain the three-dimensional stability safety factor of the gravity anchor through the strength reduction method, and analyze the influence of soil parameters on the stability of the gravity anchor in combination with the south Suzhou -Wuxi -Changzhou expressway project. The relative importance of each soil parameter is clarified. [ABSTRACT FROM AUTHOR]

BACKGROUND: Preliminary studies have shown that panax notoginseng saponins can promote the repair of osteocyte ultrastructure in a rabbit with alcohol-induced osteonecrosis of the femoral head. OBJECTIVE: To observe the structural changes of osteocytes in a rabbit with steroid-induced osteonecrosis of the femoral head treated with panax notoginseng saponins by transmission electron microscope. METHODS: Ninety 9-10 weeks old healthy male New Zealand rabbits (provided by Laboratory Center of Guangxi University of Chinese Medicine), weighting 3.5-4.0 kg were selected. Rabbit models of steroid-induced osteonecrosis of the femoral head were established by injecting modified horse serum combined with methylprednisolone sodium succinate. Fifteen rabbits died, so the remaining 75 rabbits were divided into three groups (n=25 per group), and then treated with normal saline, cervus and cucumis polypeptide or panax notoginseng saponins, respectively for 5 weeks. The structural changes of osteocytes were observed under transmission electron microscope. RESULTS AND CONCLUSION: In the normal saline group, the number of mature osteocytes was reduced, vascular endothelial cells were damaged, and mitochondria swelling, fuzzy cristae structure, nuclear fragmentation, and lipid droplets were observed. In the cervus and cucumis polypeptide and panax notoginseng saponins groups, there were more mature osteocytes and less vascular endothelial cell damage, swollen mitochondria alleviated with clear structure, and the numbers of mast adocytes and lipid droplets were decreased. The structural changes of osteocytes in the cervus and cucumis polypeptide and panax notoginseng saponins groups were significantly more encouraging than those in the normal saline group (P < 0.05). Our results indicate that show that, panax notoginseng saponins can repair the osteocyte structure of rabbits with steroid-induced osteonecrosis of the femoral head. [ABSTRACT FROM AUTHOR]