| In order to use short-fiber mixed concrete for RC excessive displacement stopper、 static loading tests on cantilever beams were conducted with short-fiber (polyvinyl alcohol (PVA))、volume mixing ratio Vf and the stirrup ratio pw as variables. Here、 their values were set as 0-0.25% and 0-1%、 respectively.[*]The results obtained from this study can be summarized as follows. The shear-load carrying capacity of RC cantilever beams is improved by mixing in PVA short fiber、 which restrains the opening of diagonal cracks. With a fiber volume mixing ratio of Vf =1%、 improvement due to the bridging effect of short fiber on the shear-load carrying capacity of RC can be expected、 as is the case with a stirrup ratio of pw=0.25%. The shear-load carrying capacity of RC cantilever beams can be estimated by means of a formula using the residual tensile strength of short-fiber mixed concrete with a certain safety margin.From the results of this test、 it was confirmed that the number of stirrups can be reduced by using short-fiber mixed concrete for RC excessive displacement stoppers. Accordingly、 it is considered possible to avoid structural changes to steel brackets、 and improve the economic efficiency and workability of RC excessive displacement stoppers. [*][*]鉄筋コンクリート移動制限装置への短繊維コンクリートを適用するため，PVA短繊維混入率Vfとスターラップ鉄筋比をそれぞれ0-１%，0-0.25%と変化させた片持ちRC梁に静的載荷試験を行った．その結果，短繊維体積混入率が1% の場合，短繊維の架橋効果によってせん断補強筋0.25%と同等な効果が期待できる．RC梁のせん断耐荷性は，短繊維混入コンクリートの残存引張強度を用いた式によって安全側に評価されることがわかった．また，短繊維を用いることでスターラップの鉄筋数を減らすことが出来て、鉄筋の過密配置が防止でき，RC構造の適用範囲が拡大することが出来ることがわかった． |
