課程名稱︰鋼筋混凝土學
課程性質︰土木工程學系必修
課程教師︰歐昱辰
開課學院：工學院
開課系所︰土木工程學系
考試日期（年月日）︰2018/9/27~2018/10/4
考試時限（分鐘）：壹萬零捌十分鐘
試題 :
作業二(Homework two)
繳交日期(Due date):10/4
(1)扼要回答以下問題：
(a)為何載重組合U=0.9D+1.0E+1.6H中，靜載D載重因數小於1，而非大於1（載重不放大
反而縮小）？
(b)為何載重組合U=0.9D+1.0E+1.6H中，地震力E之載重因數等於1，而非大於1（載重不
放大）？
Answer the following questions concisely:
(a) Why is the load factor of dead load (D) less than 1.0 rather than equal
to or larger than 1.0 (the load is reduced rather than magnified) in the
load combination U=0.9D+1.0E+1.6H?
(b)Why is the load factor of earthquake load (E) equal to 1.0 rather than
larger than 1.0 (the load is not magnified) in the load combination U=0.9D+
1.0E+1.6H?
(2)一矩形梁寬40cm，有效深度60cm，拉力筋為6支D29 (Ab = 6.47cm^2)，混凝土強度fc'
= 280kgf/cm^2，鋼筋降伏強度fy=4200kgf/cm^2，求φMn。
註：
(a)本題合併自97與102年高考題。
(b)假設極限狀態拉力筋降伏，但須檢核是否降伏。
A rectangular beam has a width of 40cm and an effective depth of 60 cm. It
has 6 D29(Ab = 6.47cm^2) longitudinal tension reinforcement. The compressive
strength of concrete fc' = 280kgf/cm^2. The yield strength of reinforcement
fy = 4200kgf/cm^2. Calculate φMn.
Note:
(a)This question is from a past national exam.
(b)Assume tension reinforcement yields at the ultimate condition. Need to
verify this assumption.
(3)於建築物評估時，已知一梁，b = 30cm，d = 50cm，As = 6 根 D25 = 30.4cm^2，
fc' = 140 kgf/cm^2，fy = 4200 kgf/cm^2，求φMn。
註：
(a)本題為103年結構技師考題。
(b)假設極限狀態拉力筋未降伏，但須檢核是否未降伏。
In the performence evaluation of a building, a beam is found to have b = 30
cm, d = 50 cm, As = 6 D25 bars = 30.4cm^2, fc' = 140 kgf/cm^2, and fy = 4200
kgf/cm^2. Calculate φMn.
Note:
(a)This question is from a past national exam.
(b)Assume tension reinforcement does not yield at te ultimate condotion.
Need to verify this assumption.