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No.14 (1977/09) >

Title :沖縄の鉄筋コンクリート構造物の耐久性 ―現況調査と考察、その5、若狭市営住宅―
Title alternative :Studies on Durability and De terioration of Reinforced Concrete Structures in Okinawa -Investigation of Existing structures, 5. "Wakasa municipal Housing"-
Authors :具志, 幸昌
和仁屋, 晴讙
伊良波, 繁雄
Authors alternative :Gushi, Yukimasa
Waniya, Haruyoshi
Iraha, Shigeo
Issue Date :30-Sep-1977
Abstract :The authors investigated on durability aspect of reinforced concrete structures in "Wakasa" munucipal Housing area. There exsit 4 apartment buildings and 154 independent houses. All of the structures are reinforced concrete structures. 4 apartment houses are located in the coast of Naha Harbor area and the rest are in the behind. Sometimes the sea waves and their sprays directly attack the above houses over the sea banks. All of the concrete of Wakasa munucipal Housing are damaged and deteriorated seriously or in some degree. The reason for the above damage is the corrosion of the steel bars embeded in the concrete of the houses, which is caused by the salt contained in the concrete. The fine aggregate used in the concrete of Wakasa Housing are sea sand and the mixing water was not tap water, so the concrete of Wakasa Houses has contained salt in some degree, but the salt come from the sprays of sea water which permeated into the concrete directly is in the majority part of the salt contained in the concrete of Wakasa Houses. The salt content of Wakasa Houses is as much as 1.91% in the weight of concrete and the average content of samples taken from damaged portions is 0.58%. The salt content of the middle schools of Naha-City is 0.23%. The following items are also clarifred through this investigation. 1. On durability aspect, the qualities of the fine and coarse aggregate in the concrete of Wakasa Houses are not so high, because their specific weights are small and absorption capacities are large. 2. The compressive strength of the concrete core samples is 161kg/cm² on the average which means pretty good strength on strength aspect, but means non-durable concrete beacause of high water-cement ratio estimated from the strength. 3. The most damaged portion of Wakasa Houses is the corridor slabs of the apartment buildings which most sprayed by the sea water. The lower surfaces of the corridor slabs are full of long and wide cracks along the steel bars and broken-down portions of the cover concrete. The beams and columns of the apartment houses are also damaged seriously, especially in the third stories. 4. The eaves of the independent houses are severly deteriorated. The steel bars embeded are exposed and long and wide cracks run everywhere in the lower surfaces of the eaves.
Type Local :紀要論文
ISSN :0387-429X
Publisher :琉球大学理工学部
URI :http://hdl.handle.net/20.500.12000/26914
Citation :琉球大学理工学部紀要. 工学篇 = Bulletin of Science & Engineering Division, University of the Ryukyus. Engineering no.14 p.55 -97
Appears in Collections:No.14 (1977/09)

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