[{"data":1,"prerenderedAt":61},["ShallowReactive",2],{"q-111180-arch_structure-5":3},{"question":4,"neighbors":26,"sameNumber":45,"prev":34,"next":37},{"id":5,"classKey":6,"session":7,"year":8,"subject":9,"number":10,"groupStem":11,"ownStem":12,"stem":12,"options":13,"answer":18,"answerKind":20,"answerS":11,"answerNote":11,"images":21,"explanation":22,"withheld":11,"deepChars":23,"freq":24,"indexable":25},"arch-111180-801-0102-005","architect","111180",111,"建築結構",5,null,"關於薄殼結構，下列敘述何者正確？",{"A":14,"B":15,"C":16,"D":17},"所有薄殼均可展開","圓筒狀薄殼之切面曲率可以為零","雙曲拋物面薄殼無法以直線構成","圓球薄殼之緯度纖維均受壓應力",[19],"B","single",[],"本題考點：薄殼結構的幾何性質——曲面的兩個主曲率、可展與不可展曲面、雙曲拋物面的直紋特性，以及圓球薄殼在垂直載重下經線方向與緯線方向的內力分佈。\n【正解理由】《建築物混凝土結構設計規範》第 12.2.3 節把薄殼界定為由厚度遠小於他向尺度之曲型薄版或摺版組成的三維空間結構，其承載行為取決於幾何形狀、受支撐狀況及作用載重性質，並列出圓頂、圓柱形殼、雙曲線的拋物線形殼等一般型式。判斷各型式的性質要回到曲面幾何：曲面上任一點有兩個互相垂直的主方向，各有一個主曲率。圓筒狀薄殼沿圓周方向是圓弧，有曲率；沿筒軸（母線）方向是直線，這個方向的切面曲率為零，所以它是「單曲面」。選項說圓筒狀薄殼之切面曲率可以為零，指的正是沿母線方向的切面，敘述正確，故選 B。\n【逐項排除】\n(A) 錯誤。能不經拉伸、撕裂就攤平成平面的「可展曲面」，只有一個主方向曲率為零的單曲面，例如圓筒、圓錐。圓頂（球面）兩個主曲率同號，雙曲拋物面兩個主曲率異號，兩者都是雙曲面，無法展開。應改為「圓筒、圓錐等單曲面薄殼可展開，圓頂、雙曲拋物面等雙曲面薄殼不可展開」。\n(B) 正確。圓柱形殼沿母線方向為直線，該方向切面曲率為零，只在圓周方向有曲率，屬單曲面；這也是它可以展開、可用直線母線構成的原因。\n(C) 錯誤。雙曲拋物面是「雙重直紋曲面」：通過曲面上任一點，都有兩條完全落在曲面上的直線。因此它雖然是雙曲面，卻能用兩組直線排列出來，模板可以用直條木料或直線排列的鋼筋組成，這正是它施工上的優勢。應改為「雙曲拋物面薄殼可以直線構成」。\n(D) 錯誤。圓球薄殼承受自重等垂直載重時，經線（子午線）方向的薄膜力全為壓力；緯線（環向）方向則不然：靠近頂部的緯度圈被往內擠而受壓，越往下方殼面越有向外撐開的趨勢，越過某一界限角之後緯線方向轉為受拉。因此並非所有緯度纖維都受壓，應改為「經線方向受壓，緯線方向上部受壓、下部受拉」。圓頂底部的環向拉力與邊界力，常由《建築物混凝土結構設計規範》第 12.2.6 節所稱加強薄殼並傳遞邊界力的邊梁等輔助構材承擔。\n【記憶點】圓筒單曲可展、球面與雙曲拋物面不可展；雙曲拋物面由兩組直線織成；圓頂經線全壓、緯線上壓下拉。",794,1,true,[27,30,33,36,39,42],{"number":28,"session":7,"stem":29},2,"有關高樓建築結構系統之特性，下列敘述何者正確？",{"number":31,"session":7,"stem":32},3,"下列混凝土抗壓強度：甲、3000 psi，乙、280 kgf\u002Fcm2，丙、30 MP…",{"number":34,"session":7,"stem":35},4,"關於結構設計時之靜載重 D 與活載重 L，下列敘述何者錯誤？",{"number":37,"session":7,"stem":38},6,"關於薄膜、纜索、與拱結構系統之敘述，下列何者錯誤？",{"number":40,"session":7,"stem":41},7,"下圖為一鋼結構的梁柱接頭所使用鋼材之拉力試驗結果，於 C 點發生材料斷裂，下列敘述何…",{"number":43,"session":7,"stem":44},8,"有關一般混凝土材料的敘述，下列何者正確？",[46,49,52,55,58],{"number":10,"session":47,"stem":48},"114180","關於圓球薄殼結構，下列敘述何者錯誤？",{"number":10,"session":50,"stem":51},"113190","關於纜索結構（cable structures）的敘述，下列何者錯誤？",{"number":10,"session":53,"stem":54},"112190","關於材料波松比 ν（Poisson's ratio），下列何者錯誤？",{"number":10,"session":56,"stem":57},"110180","關於隔震結構及制振結構之敘述，下列何者錯誤？",{"number":10,"session":59,"stem":60},"109180","有關建築物基本振動週期之敘述，下列何者錯誤？",1791863201882]