• Journal of the Korean Geotechnical Society
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• v.15 no.2
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• pp.105-127
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• 1999

Application of the soil nailing method is continuously extended in maintaining stable excavations and slopes. Occasionally, however, ground anchor support system may not be used because of space limitations in urban excavation sites nearby the existing structures. In this case, soil nailing system with relatively short length of nails could be efficiently adopted as an alternative method. The general soil nailing support system, however, may result in excessive deformations particularly in an excavation zone of the existing weak subsoils. Pretensioning the soil nails then, could play important roles in reducing deformations mainly in an upper part of the nailed-soil excavation system as well as improving local stability. In the present study, the analytical procedure and design technique are proposed to evaluate maximum pretension force and stability of the pretensioned soil nailing system. Also proposed are techniques to determine the required thickness of a shotcrete facing and to estimate probability of a failure against the punching shear. The predicted results are compared with the limited measurements obtained from the excavation site constructed by using the pretensioned soil nails. Based on the proposed procedure and technique, effects of the radius of a influence circle and dilatancy angle on the thickness of a shotcrete facing, bonded length and safety factors are analyzed. In addition, effects of the reduction of deformations expected by pretensioning of the soil nails are examined in detail throughout an illustrative example and FLAC$^{2D}$ program analysis.s.

• Journal of Korean Foot and Ankle Society
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• v.18 no.3
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• pp.108-114
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• 2014

Purpose: Ligament reattachment technique using a suture anchor appears to show satisfactory functional outcomes and mechanical stability compared with conventional bone tunnel technique. This study was prospectively conducted in order to evaluate functional outcomes of modified Brostrom procedures using the suture bridge technique for chronic ankle instability in athletes. Materials and Methods: Twenty eight athletes under 30 years of age were followed for more than two years after undergoing the modified Brostrom procedure using the suture bridge technique. Functional evaluation consisted of the foot and ankle outcome score (FAOS), foot and ankle ability measure (FAAM) score. Range of motion and time to return to exercise were evaluated using a periodic questionnaire. Talar tilt angle and anterior talar translation were measured through stress radiographs for evaluation of mechanical stability. Results: FAOS improved significantly from preoperative mean 59.4 points to 91.4 points (p<0.001). Daily living and sport activity scores of FAAM improved significantly from preoperative mean 50.5, 32.5 points to 94.8, 87.3 points, respectively (p<0.001). Talar tilt angle and anterior talar translation improved significantly from preoperative mean $16.8^{\circ}$, 13.5 mm to $4.2^{\circ}$, 4.1 mm at final follow-up (p<0.001). Times to return to exercise were as follows: mean 10.2 weeks in jogging, 15.4 weeks in spurt running, 13.1 weeks in jumping, 11.5 weeks in walking on uneven ground, 9.1 weeks in standing on one leg, 7.2 weeks in tip-toeing gait, 8.4 weeks in squatting, and 10.6 weeks in descending stairs. Conclusion: Modified Brostrom procedure using the suture bridge technique showed satisfactory functional outcomes for chronic ankle instability in athletes. Optimal indication and cost-effectiveness of the suture bridge technique will be studied in the future.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.25 no.2
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• pp.75-81
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• 1989

In this paper, the authors describe on the field experiment of the newly designed actual stow net, standing on the result of the model experiment to examine the performance of the conventional net and the newly designed net, presented in two previous reports of this series. Concurrently the additional experiment to find out the possibility of changing of operating system from the side to the stern was carried out. 1. Fundamental shape of the experimented net was 20 times aslarge asthe newly designed model net. Performance of the net was detected by using two ultrasonic echo sounders: one was set downward at the top-most spreader of the shearing device to detect the opening height of the device from the sea bed, and the other sidewise at the starboard top-most spreader to detect the top-most opening width of the devices. Opening height of the newly designed net showed about 3m smaller than the conventional net at slow current of 0.6m/sec and less but it overcome 1m at speedy current of 0.8m/sec and more. Opening width of the newly designed net was 1.4 times as large as that of the conventional net, ant the front projection area of the newly designed net mouth was estimated as 1.3~1.6 times as large as that of the conventional net. 2. The experiment on the stern operating system was tightly limited by the structure of the ship employed in the experiment, which was a stern trawler of 2275 GT. The ship confronted by the wind with main anchor, while the net was put over the stern slipway and the hauling line of shearing device was operated through the top rollers of gallows. The experiment was very suggestive in the view point to mechanize the operating system, and so to decrease the man power except the following question. The of bow-stern line of ship, and that of net is much different.