• Structural Engineering and Mechanics
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• v.39 no.4
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• pp.521-539
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• 2011

Jilin highway concrete bridge is located in the center of Jilin City, which is positioned in the middle part in Jilin Province in the east north of China. This bridge crosses the Songhua River and connects the north and the south of Jilin City. The main purpose of damages inspection of the bridge components is to ensure the safety of a bridge and to identify any maintenance, repair, or strengthening which that need to be carried out. The damages that occur in reinforced concrete bridges include different types of cracks, scalling and spalling of concrete, corrosion of steel reinforcement, deformation, excessive deflection, and stain. The main objectives of this study are to inspect the appearance of Jilin highway concrete bridge and describe all the damages in the bridge structural members, and to evaluate the structural performance of the bridge structure under dead and live loads. The tests adopted in this study are: (a) the depth of concrete carbonation test, (b) compressive strength of concrete test, (c) corrosion of steel test, (d) static load test, and (e) dynamic load test. According to the damages inspection of the bridge structure appearance, most components of the bridge are in good conditions with the exception arch waves, spandrel arch, deck pavement of new arch bridge, and corbel of simply supported bridge which suffer from serious damages. Load tests results show that the deflection, strain, and cracks development satisfy the requirements of the standards.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.2 no.1
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• pp.37-44
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• 2009

Prolotherapy, the technology for strengthening lax ligaments, has found increased acceptance in recent years. Prolotherapy involves the injection of the irritant solutions into the weakened or stretched ligaments which are a source of chronic pain. This induces an inflammatory response which mimics the normal repair sequence. Various musculoskeletal disorders of lower extremities such as degenerative arthrtitis, ligament and tendon injuries can be treated with prolotherapy. Prolotherapy is a very good, powerful nonsurgical conservative treatment in various musculoskeletal disorders. Ultrasound exam is very useful to find and confirm the exact location of disorders and check the progress in prolotherapy practices.

• Computers and Concrete
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• v.16 no.3
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• pp.399-414
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• 2015

Nowadays, fiber reinforced polymer (FRP) composites are widely used for rehabilitation, repair and strengthening of reinforced concrete (RC) structures. Also, recent advances in concrete technology have led to the production of high strength concrete, HSC. Such concrete due to its very high compression strength is less ductile; so in seismic areas, ductility is an important factor in design of HSC members (especially FRP strengthened members) under flexure. In this study, the Adaptive Neuro-Fuzzy Inference System (ANFIS) and multiple regression analysis are used to predict the curvature ductility factor of FRP strengthened reinforced HSC (RHSC) beams. Also, the effects of concrete strength, steel reinforcement ratio and externally reinforcement (FRP) stiffness on the complete moment-curvature behavior and the curvature ductility factor of the FRP strengthened RHSC beams are evaluated using the analytical approach. Results indicate that the predictions of ANFIS and multiple regression models for the curvature ductility factor are accurate to within -0.22% and 1.87% error for practical applications respectively. Finally, the effects of height to wide ratio (h/b) of the cross section on the proposed models are investigated.

• Structural Engineering and Mechanics
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• v.30 no.4
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• pp.403-426
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• 2008

Externally bonding fiber reinforced polymer (FRP) sheets with an epoxy resin is an effective technique for strengthening and repairing reinforced concrete (RC) beams under flexural loads. Their resistance to electro-chemical corrosion, high strength-to-weight ratio, larger creep strain, fatigue resistance, and nonmagnetic and nonmetallic properties make carbon fiber reinforced polymer (CFRP) composites a viable alternative to bonding of steel plates in repair and rehabilitation of RC structures. The objective of this investigation is to study the effectiveness of CFRP sheets on ductility and flexural strength of reinforced high strength concrete (HSC) beams. This objective is achieved by conducting the following tasks: (1) flexural four-point testing of reinforced HSC beams strengthened with different amounts of cross-ply of CFRP sheets with different amount of tensile reinforcement up to failure; (2) calculating the effect of different layouts of CFRP sheets on the flexural strength; (3) Evaluating the failure modes; (4) developing an analytical procedure based on compatibility of deformations and equilibrium of forces to calculate the flexural strength of reinforced HSC beams strengthened with CFRP composites; and (5) comparing the analytical calculations with experimental results.

• Physical Therapy Rehabilitation Science
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• v.11 no.3
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• pp.279-284
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• 2022

Objective: This study was conducted to confirm the effect of physiotherapy on the balance and walking in dog with sciatic nerve injury and degenerative arthritis of stifle joints. Design: Single case study Methods: The dog walked abnormally for six months and was administrated in S animal hospital. The dog's right hindlimb was operated for cranial cruciate ligament repair and the dog had been taking a nonsteroidal anti-inflammatory analgesic before being refered. There was severe degenerated osteoarthritis in the right hindlimb. During stance and walking, the right hindlimb was often shown partial weight bearing. The dog's left hindlimb was shown plantigrade stance and walking. The radiograph was shown an intact calcaneal tendon in the left hindlimb. In the neurologic examination, sciatic nerve injury in the left hindlimb was confirmed. The dog was treated using muscle strengthening, proprioceptive exercise, underwater treadmill and Laser therapy two, or three times a week for 3 months. At the 10th and 17th treatment, it was evaluated through stance and gait analyzer system to measure dog's balance and walking. Results: 3 months following physiotherapy, the dog's balance was improved in center of pressure(COP). And peak vertical force(PVF), vertical impulse(VI) was increased in right hindlimb and double stance was decreased. Conclusions: Physiotherapy may have improved the prognosis in this dog with severe osteoarthritis and sciatic nerve injury. This study suggested that animal physiotherapy is a valuable way to improve balance and walking.

• KNOM Review
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• v.23 no.1
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• pp.18-25
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• 2020

Recently, a research on a smart factory was developed from a concept of factory automation(FA) to the formation of collecting and analyzing data. This trend is accelerated as the development of communication technology(5G) and IoT devices are developed in various ways according to the field situation. In addition, digital transformation has been actively conducted in the strengthening corporate competitiveness, and various optimization studies are being conducted through process re-adjustment by combining data received from various IoT equipment and automated facilities. Therefore, in this paper, we propose a system architecture and its related components in diagnosing and repairing facility failure using a prediction system which is one of the related researches.

• Structural Engineering and Mechanics
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• v.87 no.6
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• pp.517-527
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• 2023

The severe deterioration of structures has led to extensive research on the development of structural repair techniques using composite materials. Consequently, previous researchers have devised various analytical methods to predict the interface performance of bonded repairs. However, these analytical solutions are highly complex mathematically and necessitate numerous calculations with a large number of iterations to obtain the output parameters. In this paper, an artificial neural network prediction models is used to calculate the interfacial stress distribution in RC beams strengthened with FRP sheet. The R2value for the training data is evaluated as 0.99, and for the testing data, it is 0.92. Closed-form solutions are derived for RC beams strengthened with composite sheets simply supported at both ends and verified through direct comparisons with existing results. A comparative study of peak interfacial shear and normal stresses with the literature gives the usefulness and effectiveness of ANN proposed. A parametrical study is carried out to show the effects of some design variables, e.g., thickness of adhesive layer and FRP sheet.

• Earthquakes and Structures
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• v.25 no.6
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• pp.443-454
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• 2023

Steel shear walls are used to strengthen steel and concrete structures. One such system is Partial Attached Steel Shear Walls (PASSW), which are only connected to frame beams. This system offers both structural and architectural advantages. This study first calibrated the numerical model of RC frames with and without PASSW using an experimental sample. The seismic performance of the RC frame was evaluated by 30 non-linear static analyses, which considered stiffness, ductility, lateral strength, and energy dissipation, to investigate the effect of PASSW width and column axial load. Based on numerical results and a curve fitting technique, a lateral stiffness equation was developed for frames equipped with PASSW. The effect of the shear wall location on the concrete frame was evaluated through eight analyses. Nonlinear dynamic analysis was performed to investigate the effect of the shear wall on maximum frame displacement using three earthquake records. The results revealed that if PASSW is designed with appropriate stiffness, it can increase the energy dissipation and ductility of the frame by 2 and 1.2 times, respectively. The stiffness and strength of the frame are greatly influenced by PASSW, while axial force has the most significant negative impact on energy dissipation. Furthermore, the location of PASSW does not affect the frame's behavior, and it is possible to have large openings in the frame bay.

• Journal of Korean Orthopaedic Sports Medicine
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• v.1 no.1
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• pp.79-88
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• 2002

Purpose: In this prospective, randomized study, we compared the results of early motion versus conventional immobilization after the arthroscopic Bankart repair. Materilal and Methods : We performed an arthroscopic Bankart repair using suture anchors in 62 patients with traumatic anterior shoulder instability and randomized them into two groups; Group 1 (n=28; mean age, 28 years) underwent three-week of immobilization and conventional rehabilitation program, while Group 2 (n=34; mean age, 29 years) underwent an accelerated rehabilitation program with staged range of motion and strengthening exercises starting from the immediate postoperative day. Selected patients were non-athletes with a classic Bankart lesion and a robust labrum. Analysis of outcome included pain scores (6-week and follow-up: 31(9 months), range of motion, return to activity, recurrence, patients’ satisfaction with each program, and shoulder scores (ASES, UCLA, and Rowe). Results : The recurrent rate was not different between the two groups (2 anterior apprehension from each group) (p=0.842). Patients with accelerated rehabilitation resumed functional range-of-motion faster and returned earlier to the functional level of activity (p<0.05). Accelerated rehabilitation decreased postoperative pain and more patients were satisfied with this program (p<0.05). No differences were found between the two groups at the follow-up with regards to the shoulder scores, return to activity, pain score, and the range-of-motion. Conclusions : Early mobilization after arthroscopic Bankart repair does not increase the recurrence rate in selected patients. Although the final outcomes are similar in both groups, the accelerated rehabilitation program promotes functional recovery and reduces postoperative pain, which enables patients an early institution of desired activities.

• Journal of the Korea Concrete Institute
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• v.18 no.3 s.93
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• pp.431-438
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• 2006

The determination of the depth of deteriorated concrete is one of the main problems in the structural assessment of concrete structures that have been subjected to a fire. This information is particularly important in order to optimize the future operations of repair/strengthening, or in decision-making concerning a possible demolition. The purpose of this study is to propose evaluation technique of damaged depth of concrete exposed at high temperature. In order to evaluate damaged depth of core picked at member under fire, the 24 specimens have been made with variables of concrete strength(20 MPa, 40 MPa, 60 MPa) and heating exposure condition in 600 and 800 for 2 hours. Color change analysis and water absorption after heating have been measured and split tensile stress test was performed to ka the residual compressive strength against the depth of specimen. The results show that the deeper of the depth from heating face, water absorption ratio is smaller and residual stress ratio is larger and the color of heated face is changed to red color. Using this technique at damage evaluation of fired structure, We evaluate damaged depth of member under fire and determine the reasonable strengthening range.