Железобетонные и каменные конструкции. Монолитное железобетонное ребристое перекрытие с балочными плитами. Учебное пособие

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d> ƒ=?,2/ =!A=23!/ %2 *%!!%ƒ,, , L“2", "/“%*,. 2 A- C !=23! C!, C%›=! !=““2% …, “2 !›… L %2 …=!3›…/. +!=… L%>›…% K/2@ … A … ,=A 2!= =!A=23!/ d , … A … 20 AA.

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p,“.21.q. A= =!A,!%"=…, *%>%……/, !=K%2=E? L …= …2!=>@…% “›=2, (a):

K O " ƒ=…/A, *=!*=“=A,; " O “"=!…/A, *=!*=“=A,

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u%A32/ C! …=ƒ…=) …/ > %KA ,… …, C!% %>@…%L =!A=- 23!/ " %K?,L *=!*=“ , C!, =…, A3 › “2*%“2,, = 2=*› > C! %2"!=? …, "/C3),"=…, “2 !›… L =!A=23!/ "“> “2", ,. C!% %>@…%+% ,ƒ+,K=. h“.% ,ƒ C%“> … +% “%%K!=› …, , !=“- “2% …, A › 3 .%A32=A, " " ƒ=…/.*=!*=“=.C!,…,A=E2 … K%> 15ds !=K%) L =!A=23!/.

e“>, *%>%……= =!A,!3 2“ “"=!…/A, *=!*=“=A,, 2% !=““2% - …, A › 3 C%C ! )…/A, “2 !›… A, %>›…% K/2@ … K%> 20ds. b*%>%……=.!=ƒA !%A “ ) …, K%>@H 40 “A , C!, ),“> “2 !›… L K%>@H ) 2/! . %>›…/ “2=",2@“ %C%>…,2 >@…/ .%A32/ (C%- C ! )…/ “2 !›…,) (“A.!,“.21).

bA “2=.“2/*%" +,K*%L C!% %>@…%L =!A=23!/ K ƒ “"=!*, !=“- “2% …, A › 3 .%A32=A, … %>›…% C! "/H=2@ 10ds.

d,=A 2! .%A32%" " ƒ=…/. *=!*=“%" C!,…,A= 2“ … A …

1 ds C!% %>@…/. “2 !›… L , … A … 6 AA, = " “"=!…/. *=!*=-

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“=. O …=ƒ…=)= 2“ C% …%!A=A " ƒ=",“,A%“2, %2 ,=A 2!= C!%-%>@…%L =!A=23!/ , 3“>%",L “"=!*,. Š%>?,…= ƒ=?,2…%+% “>%> .%A32%" %>›…= K/2@ … A … 15 AA.

p=““A%2!,A %“%K ……%“2, !=“) 2= , *%…“2!3,!%"=…, *%>%……, ,ƒ+%2%"> A/. ,ƒ A%…%>,2…%+% › > ƒ%K 2%…=.

p,“.22.q. A= “%C! › …, =!A=23!/ *%>%……/:

= O “ -3… =A …2%A; K, " O “ *%>%……=A, "/H > ›=? +% .2=›=

o!, ,ƒ+%2%"> …,, *%>%…… ,ƒ A%…%>,2…%+% › > ƒ%K 2%…= C!%-%>@…/ “2 !›…, 3 %“…%"=…, *%>%…… “2/*3E2“ “ "/C3“*=A, ,ƒ -3… =A …2= (!,“.22,=), = "" !.3 O “% “2 !›… A, *%>%…… "/- H > ›=? +% .2=›= (!,“.22,K,").

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5.2. p=“ 2 *% %……/

o! › ) A C!,“23C,2@ * !=“) 23 *%>%……/, … %K.% ,A% ƒ…=2@ %K?3E *%…“2!3*2,"…3E “. A3 ƒ =…, , +% .2=›…%“2@, *%…“2!3* ,E C ! *!/2, , " >,),…/ C%“2% ……%L , "! A ……%L …=+!3ƒ%*, L- “2"3E?,.…= .2=›=..d> ,ƒ+%2%"> …, *%>%…… %K/)…% C!,…,A=E2 *>=““ K 2%…= … …,› b20, " *=) “2" !=K%) L =!A=23!/ ,“C%>@ƒ3E2 “2=>@ *>=““%" `-o ,>, A-III, = > .%A32%" O “2=>@ *>=““= A-I.

p=“) 2 *%>%……/ "*>E)= 2 " “ K : C% “) 2 “›,A=E? L “,>/

N=N >+N*!; %C! > …, !=ƒA !%" C%C ! )…%+% “ ) …, *%>%……/ (Ab=akxbk) , C>%?= , “ ) …, C!% %>@…%L =!A=23!/ As. b%ƒ…,*=-

E?, " *%>%…… ,ƒ+,K=E?, A%A …2/ C!, › “2*%A “%C! › …,,“ !,+ > A ,ƒ-ƒ= A=>%L › “2*%“2, *%>%…… C% “!="… …,E “ › “2- *%“2@E !,+ > %K/)…% … 3),2/"=E2 , 3“>%"…% C%>=+=E2 l = 0. m=+!3ƒ*= …= *%>%……3 C ! = 2“ %2 +>="…%L K=>*, C ! *!/- 2, !=““A=2!,"= A%+% .2=›= , %2 *%>%……/ "/H > ›=? +% .2=›=. b!=“) 2…3E “,>3 N … %K.% ,A% "*>E)=2@ 2=*› “%K“2" ……/L

" “ *%>%……/.o!, C% “) 2 “%K“2" ……%+% " “= C! "=!,2 >@…/ !=ƒA !/ “ ) …, *%>%……/ “> 3 2 …=ƒ…=)=2@ !="…/A, H,!,… ! K!= +>="…%L K=>*, C>E“ 5#10 “A.

b “%%2" 2“2",, “ …%!A=A, [1, 2] C!, !=“) 2 …2!=>@…% “›=2/. › > ƒ%K 2%……/. .> A …2%" "“ + = %>› … 3),2/"=2@-

ϕs , ϕb O %C! > E2“ ,ƒ 2=K>.8 " ƒ=",“,A%“2, %2 %2…%H …,L N >/N , l0/bk, + N >= NO N*!O !=“) 2…= C!% %>@…= “,>= %2

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>,2 >@…% L“2"3E? L …=+!3ƒ*,; N*!O !=“) 2…= C!% %>@…= “,>= %2 *!=2*%"! A ……% L“2"3E? L …=+!3ƒ*,; l0 O !=“) 2…=>,…= *%>%……/ A…%+%.2=›…/. ƒ =…,L; bk O H,!,…= *%>%……/.

Š = K > , = 8

d> “K%!…/. C ! *!/2,L l0 =m, > A%…%>,2…/. l0 = 0,7m; mO "/“%2= .2=›= (!=““2% …, A › 3 …2!=A, 3ƒ>%").

N > , N*! %C! >,A ,ƒ ƒ=",“,A%“2 L:

N > = A+!.C>.*%>.q“!C.2+p*%>.(*m)

+ A+!.C>.*%>= l+> l"2 O +!3ƒ%"= C>%?= @ C!, C% “) 2 …=+!3ƒ*,,L“2"3E? L …= *%>%……3,

q“! = G+>/ lC> l"2 *m/A2 O “! …,L “%K“2" ……/L " “ 1A2 C ! - *!/2, ,

G+> %C! > A C% -%!A3> (14) O “%“! %2%) ……= “,>= C!, !=“) 2 +>="…%L K=>*, C ! *!/2, ,

l+> O C!%> 2 +>="…%L K=>*,; l"2 O C!%> 2 "2%!%“2 C ……%L K=>- *,; lC> O C!%> 2 C>,2/; C.2 O ),“>% .2=› L " ƒ =…,,, C ! *!/2,L;

p*%>= bk a* m γ›/K γf C.2 (*m) O “%K“2" ……/L " “ *%>%……/; + bk a* = `b OC>%?= @ C%C ! )…%+% “ ) …, *%>%……/;

γ›/K = 25 *m/A3; γf =1,2;

N*! = A+!.C>.*%>.!(C.2O1) (*m),

+ ! # C%> ƒ…= ("! A ……= ) !=“) 2…= …=+!3ƒ*= …= C ! *!/2, (“A.2=K>, 3 11).

54

m=“/? …, *%>%……/ =!A=23!%L %>›…% K/2@ … A … 0,3%, = " +,K*,. *%>%……=. (l0 /h > 10), !=K%2=E?,. " 3“>%", . C!%-%>@…%+% ,ƒ+,K=, O 0,5%; …=,K%>@H …=“/? …, … %>›…% C! "/H=2@ 3%.

nK/)…% C!% …2 =!A,!%"=…, C!,…,A= 2“ " C! >=. μ %= =(0,8#2,0) %.

q 3) 2%A “*=ƒ=……%+% "/H , ƒ= = ,A“ !=ƒA !=A, C%C ! )…%+% “ ) …, *%>%……/ (Ab=ak]bk), = 2=*› C! "=!,2 >@…% C!,A A *%.--, , …2 C!% %>@…%+% ,ƒ+,K= ϕ ≈ 0,8÷0,9 , ,ƒ ƒ=",“,A%“2, (31) %C! >,A C>%?= @ C!% %>@…%L =!A=23!/

Nϕ − Rb Ab As = m

Rs

Š C !@, ƒ…= As , Ab, 32%)…,A ,ƒ ƒ=",“,A%“2, (33) *%.--,-, …2 C!% %>@…%+% ,ƒ+,K= ϕ “ 3) 2%A =……/. 2=K>.8 , "/C%>…,A C!%" !*3 C!%)…%“2, C% -%!A3>=A (31) ,>, (32), + μ = As/Ab ; nC! >," %*%…)=2 >@…% !=ƒA !/ C%C ! )…%+% “ ) …, *%- >%……/ , C>%?= @ =!A=23!/, C% K,!=E2 ),“>% , ,=A 2! “2 !›- … L, = 2=*› "/K,!=E2 2,C .%A32%" , !=““2% …, A › 3 …,A,

“ 3) 2%A *%…“2!3*2,"…/. 2! K%"=…,L, ,ƒ>%› ……/. "/H .

5.3. o!% *2,!%"=…, -3…)= …2=

n2 >@…/ A%…%>,2…/ › > ƒ%K 2%……/ -3… =A …2/ >=E2 C,!=A, =>@…%L ,>, “23C …)=2%L -%!A/.

b “23C …)=2/. -3… =A …2=. ),“>% “23C … L C!,…,A= 2“ ,“-

.% ,ƒ %K? L "/“%2/ -3… =A …2= H-. o!, .2%A ! *%A … 3 2“ …=ƒ…=)=2@ “> 3E? ),“>% “23C … L: C!, "/“%2 -3… =A …2= H- ≤ 450 AA O % …3 “23C …@, C!, 450 < H- ≤ 900 AA O " “23- C …,, C!, H- > 900 AA O 2!, “23C …,.

b/“%2= *=› %L “23C …, , %K?= "/“%2= -3… =A …2= C!,- …,A=E2“ *!=2…/A, 150 AA.

p=ƒA !/ “23C … L (ƒ= ,“*>E) …, A …,›… L) %K/)…% …=ƒ…=)=- E2 2=*, )2%K/ ".% ?, 3+>/ 3“23C%" !=“C%>=+=>,“@ …= C>%“*%“2,, C!%" ……%L C% 3+>%A 450 %2 %“…%"=…, *%>%……/ (!,“. 23).

c>3K,…= ƒ=>%› …, -3… =A …2%" H3 )=? "“ +% ,*23 2“ +>3K,…%L C!%A !ƒ=…, .

55

p,“.23.p=“) 2…= “. A= A%…%>,2…%+% -3… =A …2=

b C!%,ƒ"% “2" ……/. ƒ =…, . +>3K,…= ƒ=>%› …, -3… =- A …2%" )=“2% %C! > 2“ %2A 2*%L %“…%"=…, %K%!3 %"=…, .

5.4. p=“ 2 -3…)= …2=

d> ,ƒ+%2%"> …, › > ƒ%K 2%……/. -3… =A …2%" C!,A … E2 %K/)…% K 2%…/ *>=““= b10, b15 , =!A=23!…3E “2=>@ *>=““= `-o. p=“) 2 %2 >@…% “2% ? +% › > ƒ%K 2%……%+% -3… =A …2= C%…2!=>@…3E …=+!3ƒ*3 “%“2%,2 " %C! > …,, !=ƒA !%" C% %H"/ -3… =A …2=, +% "/“%2/ , C>%?= , =!A=23!/. o!, .2%A !=ƒA !/ C% %H"/ -3… =A …2= %C! > E2“ C% 3“,>, A %2 …%!A=2,"…%L …=+!3ƒ*, , ƒ= =……%A3 !=“) 2…%A3 “%C!%2,"> …,E +!3…2= R+! “ 3) 2%A “%K“2" ……%+% " “= -3… =A …2= , " “= +!3…2= …= +% 3“23C=.. b/“%2= › -3… =A …2= , C>%?= @ =!A=23!/ %C! - > E2“ C% 3“,>,E %2 ! =*2,"…%+% ="> …, +!3…2= (%“…%"=…, ) %2 !=“) 2…%L …=+!3ƒ*,, C ! ="= A%L *%>%……%L …= -3… =A …2. Š=* *=* C!, !=“) 2=. %K/)…% …%!A=2,"…% 3“,>, %2 >@…% … 3),2/"=>%“@, 2% +% A%›…% %C! >,2@ > …, A !=“) 2…%+%

ƒ…=) …, N …= 3“! … ……/L *%.--, , …2 …= ›…%“2, C% …=- +!3ƒ* , *%2%!/L A%›…% C!,… 2@ !="…/A γf = 1,15.

56

o!, !=“) 2 -3… =A …2= ="> …, …= +!3…2 C% +% C% %H"%L 3“>%"…% C!,…,A= 2“ !="…%A !…% !=“C! > ……/A.

o>%?= @ C% %H"/ -3… =A …2= %C! > 2“ C% -%!A3>

+ p O !=“) 2…= C!% =">,"=E?= “,>=; H%- O !=K%)= "/“%2=

-3… =A …2=; !“!=2(a* + b* + 2H%-) O “! … =!,-A 2,) “*% A › 3 C !,A 2!%A " !.… +% , …,›… +% %“…%"=…, C,!=A, /;

Rbt O !=“) 2…% “%C!%2,"> …, K 2%…= C!, !=“2 › …,,; k O .A- C,!,) “*,L *%.--, , …2, C!,…,A= A/L > 2 › >/. K 2%…%" !="…/A ,…, .

b >,),…= C!% =">,"=E? L “,>/ p C!,…,A= 2“ !="…%L !=“- ) 2…%L “,> N, L“2"3E? L " “ ) …,, *%>%……/ 3 " !.= -3… =- A …2=, ƒ= "/) 2%A ! =*2,"…%+% ="> …, C% C>%?= , %“…%"=…, C,!=A, / C!% =">,"=…, :

o! "=!,2 >@…3E "/“%23 -3… =A …2= A%›…% %C! >,2@ ,ƒ 3“>%", C!%)…%“2, +% C!%2," “! ƒ= (C!% =">,"=…, ) C% C !,- A 2!3 *%>%……/, *%2%!% ƒ=C,“/"= 2“ " “> 3E? A ", :

57

+ R“! ≈ 2Rbt O C!%)…%“2@ K 2%…= …= “! ƒ.

o% “),2=" C% -%!A3> (36) C!% =">,"=E?3E “,>3 p, A%›…% C!%" !,2@ 3“>%", (35). j=* C!=",>%, %…% 3 %"> 2"%! 2“ C!,

+ Q = b-l1σ+! O !=“) 2…= C%C ! )…= “,>= C% +!=…, “23C …,, "2%!%L “…,ƒ3 (%…= %C! > 2“ *=* > *%…“%>@…%L K=>*, >,…%L

l1, ƒ=+!3› ……%L ! =*2,"…/A ="> …, A +!3…2= (σ+!); b-O H,!,…=

-3… =A …2=; h01O !=K%)= "/“%2= C !"%L “23C …, -3… =A …2=. o%“> C% “2=…%"*, " .2% 3“>%", "/!=› …, > Q C%>3),A

“> 3E?3E -%!A3>3 > %C! > …, A,…,A=>@…%L !=K%) L "/- “%2/ C !"%L (…,›… L) “23C …, -3… =A …2=:

o%>…= "/“%2= …,›… L “23C …, h1= h01+a.o!, .2%A “> 3 2 C%A…,2@, )2% 2%>?,…= ƒ=?,2…%+% “>% = C!, …=>,),, K 2%……%L

C% +%2%"*, C% C% %H"%L -3… =A …2= C!,…,A= 2“ 35 AA, = C!,%2“32“2",,O 70 AA.

5.5. `! ,!%"=…, -3…)= …2=

o>%?= @ “ ) …, !=K%) L =!A=23!/ %C! > 2“ ,ƒ !=“- ) 2= …= ,ƒ+,K *%…“%>@…/. "/“23C%" -3… =A …2= " “ ) …, . IOI (3 +!=…, *%>%……/) , IIOII (3 +!=…, "2%!%+% 3“23C=).

hƒ+,K=E?, A%A …2/ " .2,. “ ) …, . 2=*%"/:

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o>%?= @ “ ) …, =!A=23!/ …= "“E H,!,…3 -3… =A …2= b-

"*=› %A …=C!="> …,, A%›…% …=L2, ,ƒ ƒ=",“,A%“2,, C!,… "

"… L η =0,9:

…%L !=“) 2…%A3 “ ) …,E =!A=23!/ *%>%…… 3 %K! ƒ= -3… =A …2=.

p,“.24.q. A= =!A,!%"=…, A%…%>,2…%+% -3… =A …2=

59