[{"data":1,"prerenderedAt":61},["ShallowReactive",2],{"q-110180-arch_construction-11":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-110180-801-0103-011","architect","110180",110,"建築構造與施工",11,null,"木材在進行含水率測試時，常用絕乾法進行。絕乾法為將試片置於烘箱中乾燥至恆量之過程。若有一試片乾燥前質量（m1）為 500 g，乾燥後之質量（m0）為 450 g，試問本結構用木材之含水率為何？",{"A":14,"B":15,"C":16,"D":17},"9%","10%","11%","12%",[19],"C","single",[],"本題考點：木材含水率的定義與絕乾法（烘乾法）的計算；關鍵在於含水率的分母是「絕乾重」（m0），不是烘乾前的重量（m1）。\n【正解理由】絕乾法是把試片放進烘箱烘到恆重，此時試片內的水分視為全部排出，剩下的就是木材實質本身的重量，也就是絕乾重 m0。木材含水率定義為「所含水分重量占絕乾重的百分比」，公式為：含水率 =（m1 − m0）／ m0 × 100%。先求水分重量：m1 − m0 = 500 g − 450 g = 50 g；再除以絕乾重：50 g ／ 450 g × 100% ≈ 11.11%，四捨五入取整為 11%，與選項 (C) 相符。之所以拿絕乾重當分母，是因為絕乾重是同一塊木材不論乾濕都不會改變的基準量；拿會隨水分增減而變動的 m1 當分母，算出來的百分比就失去比較的意義。故選 C。\n【逐項排除】\n(A) 9%：不符合。正確的含水率約為 11.11%，9% 比正確值偏低，數值不符；要改成以水分重 50 g 除以絕乾重 450 g，才得到正確的 11%。\n(B) 10%：不符合。這個數值是把分母誤用為烘乾前的重量 m1 所得：50 g ／ 500 g × 100% = 10%，算出來的是「濕基含水率」（水分占含水木材總重的比例），而題目問的木材含水率以絕乾重為分母。分母一錯，結果就比正確值偏低；改成分母用 m0 = 450 g，結果才是 11%。\n(C) 11%：符合。水分重 50 g 除以絕乾重 450 g，乘以 100% 得 11.11%，取整為 11%，正是絕乾法下木材含水率的定義值。\n(D) 12%：不符合。正確值約 11.11%，12% 比正確值偏高，取整後也不會得到 12%；分子應為 m1 − m0 = 50 g、分母應為 m0 = 450 g，結果只能是 11%。\n【記憶點】木材含水率一律「水重除以絕乾重」：分母用烘乾後的 m0，用 m1 當分母就會掉進 10% 的陷阱。",905,1,true,[27,30,33,36,39,42],{"number":28,"session":7,"stem":29},8,"關於鋼材的性質敘述，下列何者正確？",{"number":31,"session":7,"stem":32},9,"目前塗料在建築及室內使用日漸廣泛，關於塗料敘述下列何者錯誤？",{"number":34,"session":7,"stem":35},10,"某鋁窗依據 CNS3092「鋁合金製窗」規定進行如下圖之試驗規劃，試問該鋁窗所進行的…",{"number":37,"session":7,"stem":38},12,"低輻射鍍膜玻璃或稱 Low-E 玻璃，其放射率（輻射率）ε 值須達到 CNS1583…",{"number":40,"session":7,"stem":41},13,"關於外牆磁磚的敘述，下列何者正確？",{"number":43,"session":7,"stem":44},14,"下列何者不是混凝土表面（不與模板接觸面）在完成澆置及修飾後可選用之養護方法？",[46,49,52,55,58],{"number":10,"session":47,"stem":48},"114180","下列有關混凝土材料之敘述何項正確？",{"number":10,"session":50,"stem":51},"113190","下列有關紅磚之敘述何項正確？",{"number":10,"session":53,"stem":54},"112190","依據建築物無障礙設施設計規範，無障礙停車位，下車區之線條應為何種顏色？",{"number":10,"session":56,"stem":57},"111180","某基地欲設計一建築物，下列規模何者不符合建築物磚構造設計及施工規範之規定？",{"number":10,"session":59,"stem":60},"109180","有關混凝土摻料之規定，下列敘述何者錯誤？",1791863204018]