• Journal of the Korea Concrete Institute
• /
• v.18 no.3 s.93
• /
• pp.321-330
• /
• 2006

In order to remodel old aged reinforced concrete buildings, it is often required to extend the residence area of the buildings by increasing the slab area. The slab area is usually extended by attaching a new slab to the existing slab with hinged joint or rigid joint. Transmission of the loads of the attached slabs to the existing slabs depends on the connecting methods, such as hinged or rigid connection. In this research, 8 specimens and 24 RC slabs connected by rigid joints were tested. The new slab was connected to the existing slab by three types of rigid joints using dowel bars and longitudinal tensile bars. Main parameters of the slabs were three types of the rigid joints, anchor length of steel bars(0, 50, 60, 100, and 120mm), development length of steel bars(100, 200, and 300mm), and the spacing of the steel bars(150, 200, 300, and 450mm). The test results indicated that the flexural strength of the RC test slabs having various types of rigid joints was approximately the same to that of the slab without any connections.

• Journal of Trauma and Injury
• /
• v.22 no.1
• /
• pp.51-56
• /
• 2009

Purpose: The purpose of this study was to investigate environmental factors contributing to childhood home slip-down injuries. Methods: Among a total of 2,812 injured children in our Customer Injury Surveillance System (CISS), we performed a prospective study on 262 children with home slip-down injuries who visited the pediatric emergency department of Asan Medical Center between March 2008 and February 2009. We made a frequency analysis on parameters such as activities just before the accident, the presence of any obstacles or lubricant materials, specific home place in the home where the injuries occurred, flooring materials on which the slip-down happened, additional objects hit after slip down, the site and kind of injury, the duration of therapy, and the disposition. Results: Walking was the most common activity just before the injury. Because rooms and bathrooms were most common places in the home for slip down injuries, laminated papers/ vinyl floor coverings and tiles were the most common flooring materials used in the places where the injuries occured. Most commonly, no obstacles caused the children to slip down, but the furniture, stairs, doorsills, wetness, or soapy fluid followed after that. Over half of the children who slipped (58%) also collided with other than the floor itself after the slip-down, most common objects hit were the edges of the furniture, and doorsills, followed by stairways. The head and neck were the most commonly injured sites, and a laceration was the most common kind of injury. Most children needed less than 1 week of therapy, only 4 children (1.53%) admitted. There were no mortalities. Conclusion: The environmental factors contributing to slip-down injuries were the bathroom, laminated papers/vinyl floors, the furniture, stairs, doorsills, and wetness or soapy fluid. Especially, the furniture, stairs, and doorsills can be both primary obstacles and secondary collision objects. For the safety of our children, we must consider these factors on housing, when decorating or remodeling our house.