外文翻譯---試驗(yàn)研究鋼筋混凝土柱改造方法-文庫吧資料
2025-05-22 08:44本頁面
【正文】 d PCS. All specimenswere tested under axial pression loading only. Applied load and displacement weremeasured for all specimens throughout testing until failure. Additionally, response of theloaded specimens was observed and documented throughout the testing. Behavior of thenewly introduced PCS reinforcement was pared with traditionally used retrofitapplications already currently utilized in the structural engineering industry. Advantagesand disadvantages of each retrofit measure were identified. Additionally, model conceptswere presented for the response of concrete jacket retrofitted columns based on the workof Mander et al. (1988) and Cai (1987). Project Summary Seventeen circular columns were constructed and tested to failure in pression. First,similar reinforced concrete base columns were constructed with spiral transverse reinforcement. All base specimens had the same dimensions, transverse, and longitudinaleinforcement. The base specimens were then retrofitted with the different retrofitmethods previously discussed. One specimen, referred to as the base specimen, wastested without any retrofit applied. Three specimens were retrofitted with a spiral rebarreinforced concrete jacket. Two specimens were reinforced with a welded wire fabricreinforced concrete jacket. Three specimens were retrofitted with FRP wraps and twomore specimens were retrofitted with steel jackets. In addition, six specimens wereretrofitted with a PCS reinforced concrete jacket, including two different thicknesses ofPCS. Nine specimens had the entire cross section of the base column and retrofit area simulated a retrofit condition when the applied load is distributed across the entirecross section. Five specimens had the cross section of only the base column loaded,which simulated a condition when the load is only applied to the original member. Threeother specimens had increased lateral reinforcement spacing with similar transversereinforcement strength per spacing. These specimens also had the entire retrofit and basecolumn crosssection loaded. RETROFIT OF EXISTING STRUCTURES Many structures have historically been constructed using reinforced concrete. Typicalordinary concrete consists of four constituents: gravel, sand, water, and concrete has some type of reinforcement, typically steel, bined withconcrete to produce a stronger system than plain concrete. Concrete is strong in pression but weak in tension. Tensile forces cause concrete to crack and eventuallyfail in a brittle manner at stresses significantly lower than the pression strength ofconcrete. Steel, or another type of reinforcement material, can be used to pensate forthe weak tensile strength of concrete. This system is referred to as reinforced concrete. As reinforced concrete ages, a variety of detrimental effects can occur. These includespalling, flaking, or cracking of the concrete, and subsequent corrosion of the reinforcingsteel. These occurrences can significantly affect the strength of structural displaying these adverse affects may be rehabilitated using an appropriateretrofit method. Retrofitting is typically done for two reasons: rehabilitation or strengthening. As previously discussed, rehabilitation is fixing the structural deficiencies of a damaged structure or structural member. This may be necessary for aging members that no longerdisplay the strength of the original design. Strengthening increases the loadcarryingcapacity of a structural member (Ersoy et al. 1993). This may be necessary if thesupported load is altered through the life of the structural member, or if current designstandards have more stringent reinforcement requirements. Addition
畢業(yè)設(shè)計(jì)相關(guān)推薦
鄂ICP備17016276號(hào)-1