混凝土结构中册习题答案
第11章
11．1 解：1、求支座截面出现塑性铰时的均布荷载q1
首先计算支座截面极限抗弯承载力MuA：
2
C20混凝土查得fc=mm, 316 As=603mm
2
x?Asfy?1fcb?603?300?94mm??bh09.6?200A
1 B x94MuA?Asfy(h0?)?603?300(465?)?75.6KNm22按弹性分析：MA?MuA12MuA12?75.6ql2?, q???25.2kNm 12l262?q1?25.2kN/m
2、计算跨中极限抗弯承载力Mu1：2
16 As=402mm
2
x?63?402?300??63mm, Mu1?402?300?465???52.3kNm
2?9.6?200?总弯矩M总?MuA?Mu1?75.6?52.3?127.9kNm 由M总
8M总8?127.9pul2???28.4kN/m 得 pu?228l63、若均布荷载同为pu,按弹性计算的支座弯矩
MAe?22M总??127.9?85.3kNm 33MAe?MAu85.3?75.6??0.114
MAe85.32
2
则调幅系数??
11．2 解：As1=AsA=644mm/m， fy=210N/mm, h0=120-20=100mm
644?210?14.1mm??bh09.6?100014Mu?644?210(100?)?12.58kNm/m
2x?M总?2Mu?25.2kNm/m
A
,
8/10@100
8/10@100 B
pu?8M总2ln?1?8?25.22?12.6kN/m 24?1B 11．3 解：塑性铰线位置如图所示。
1(l?a) ?32l?a 4l?a 2a a l
取出一块梯形板块为隔离体，对铰支座AB取力矩平衡：
A
??l?a?21?l?a??l?a??l?a??m?(l?a)?pu????a?????
224???2?3????l?a?2a?l?a??l?a?l?a??l?a?m?pu???p??apu?l?2a?????u8?8?324??24
24m?pu??l?2a??l?a?
第12章
12．1 解：
y3?10.45?0.0756影响线 0.45?4.4y2??0.80861.6y4??0.2676y1?y1 y2
y3
y4
?yi?1?0.075?0.808?0.267?2.1518?9.8?10?9.8?115?22.2kN2P22.2?min?Dmax??222.5?43kNPmax115Dmax?0.9Pmax?yi?0.9?2.15?115?0.9?247.25?222.5kNPmin?Dmin
水平荷载系数??0.12
1?0.12?3.94?10??9.8?4.098kN4
4.098Tmax,k??222.5?7.93kN115Tk?12．2 解：
1计算柱顶水平集中力Wk：柱顶标高处?z○
?1.0, 檐口处?z?1.07
Wk?W1k?W2k???0.8?0.5??2.1??0.5?0.6??1.2??1.07?0.45?6??1.3?2.1?0.12??1.07?0.45?6?7.54kN2 q1k??s?zw0B?0.8?1.0?0.45?6?2.16kN/m ○
q2k??0.5?1.0?0.45?6??1.35kN/m
Wk 3 剪力分配系数计算： ○
2.13?0.14814.387.2nB??0.369
19.510.5?8.4???0.2;10.5nA?q1k q2k
A B
C0A?3C0B?1?1?0.23??1??0.148?
3??2.96因只需相对值，故略去109?1?1?0.23??1??0.369??3?2.8681?0.008?5.757???
H3H3H31?uA????;EcI2C0AEc?14.38?2.868Ec41.24?uB?H1H1???;Ec19.5?2.96Ec57.7233
EE11??c3?41.24?57.72??98.96c3 ?uA?uBHH
?A?41.2457.72?0.417， ?B??0.583 98.9698.96B
4 计算约束反力RA、R： ○
C11A
??1??3?1?0.24??1???0.148??3.028????0.362??1??98.968?1?0.23??1???0.148?????1??3?1?0.24??1???0.369??3.008????0.3718.11??1??8?1?0.23??1???0.369???
C11B
RA?q1HC11A?2.16?10.5?0.362?8.21kN???RB?q2HC11B?1.35?10.5?0.371?5.26kN???
?R?8.21?5.26?13.47kN
5 剪力计算： ○
?A??R?Wk??0.417??13.47?7.54??0.417?21.01?8.76kN?B??R?Wk??0.583??13.47?7.54??0.583?21.01?12.25kNA柱顶剪力 VA= () B柱顶剪力 VB= ()
6 弯矩图： ○
MA底?
MB底
11q1H2?VAH??2.16?10.52?0.55?10.5?124.85kNm22
1??1.35?10.5?7?10.5?147.8kNm2MA=
MB=
