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

p,“.15.q. A= =!A,!%"=…, +>="…%L K=>*, “"=!…/A, *=!*=“=A, ("=!,=…2 2)

p=“) 2/, … %K.% ,A/ > C%“2!% …, .CE!/ A=2 !,=>%", A%›…% "/C%>…,2@ " 2=K>,)…%L -%!A (2=K>. 7).

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

o>%“*, *=!*=“/ C ! 3*>= *%L " %C=>3K*3 ! *%A … 3 2“ “% ,…,2@ !3+ “ !3+%A " C!%“2!=…“2" ……/ *=!*=“/ C!, C%- A%?, C%C ! )…/. “% ,…,2 >@…/. “2 !›… L, C!,"=!,"= A/. * C!% %>@…/A (“A. !,“. 15).

o!, !=ƒA ? …,, “2 !›… L " “ ) …,, %>›…/ 2=*› “%K>E-=2@“ “> 3E?, 2! K%"=…, :

41

1)!=““2% …, " “" 23 A › 3 “2 !›… A, %>›…% K/2@ … A … ,=A 2!= , … A … 25 AA, C!, …,›… A !=“C%>%› …,, =!A=23!/O … A … 30 AA, )2% %K “C ),"= 2“ %K/)…% C!, …=ƒ…=) …,, ),“>= C>%“*,. *=!*=“%" " ƒ=",“,A%“2, %2 H,!,…/ C!%+%…= (“A.!,“.13);

2)!=““2% …, " “" 23 A › 3 ! =A, C!, "3.! …%A !=“- C%>%› …,, %>›…% K/2@ … A … ,=A 2!= , … A … 25 AA;

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

25 AA > C!% %>@…%L =!A=23!/ , … A … 15 AAO > .%A32%".

4.4. p=“ 2 C%C ! …%L =! =23!/

C!, =! ,!%"=…,, K= %* " ƒ=…/ , *=!*=“= ,

b2%!%“2 C ……/ , +>="…/ K=>*, A%…%>,2…%+% ! K!,“2%+% C ! *!/2, A%+32 =!A,!%"=2@“ %2 >@…/A, “2 !›… A,, ,ƒ *%2%!/. “ C%A%?@E " ƒ=>@…%L C!%"%>%*, “%K,!=E2“ " ƒ=…/ *=!*=“/. n“2=…%",A“ …= %“%K ……%“2 . !=“) 2= , *%…“2!3,!%- "=…, K=>%*, =!A,!%"=……/. " ƒ=…/A, *=!*=“=A,.

o!, =!A,!%"=…,, K=>%* " ƒ=…/A, *=!*=“=A, " C%C ! )…%A “ ) …,,, *=* C!=",>%, 3“2=…=">,"=E2 " ,>, ) 2/! " 2", .%- A32%" (!,“. 16). d" " 2", .%A32%" “2=" 2 %K/)…% C!, H,!,… K=>*, b ≤ 350 AA , C!, ),“> “2 !›… L " % …%A ! 3 … K%> C 2,. o!, b > 350 AA ,>, C!, ),“> “2 !›… L " % …%A ! 3 K%> C 2, “2=" 2 ) 2/! " 2", .%A32%".

b… *%2%!/. “>3)= . C!, ƒ…=),2 >@…%L H,!,… K=>*,

,K%>@H%A *%>,) “2" “2 !›… L C!% %>@…%L =!A=23!/ “2=" 2 H “2@ ,>, =› "%“ A@ " 2" L .%A32%".

p=ƒ>,)=E2 %2*!/2/ , ƒ=*!/2/ .%A32/. b K=>*=. C! A%- 3+%>@…%+% “ ) …, %K/)…% “2=" 2 ƒ=*!/2/ .%A32/ (!,“. 16,=). d> K=>%* “ "%L…%L =!A=23!%L ƒ=*!/2/ .%A32/ %K ƒ=-

2 >@…/ > C!%2,"% L“2", "/C3),"=…,E “›=2%L =!A=23!/ %2 C!% %>@…%+% ,ƒ+,K=.

b/K!=" 2,C .%A32= ,, 3“2=…%"," ),“>% “! ƒ%" .%A32= " C%- C ! )…%A “ ) …,, K=>*,, "/C%>… E2 !=“) 2 …= L“2", “,>/ Q “ ,“C%>@ƒ%"=…, A ! *%A … = ,L C. 4.1.

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p,“.16.p=“C%>%› …, .%A32%" " C%C ! )…%A “ ) …,, K=>*, C!, =!A,!%"=…,, " ƒ=…/A, *=!*=“=A,

e“>,

Q ≤ 0,5 bh0Rbt ,

+ QO A=*“,A=>@…= C%C ! )…= “,>= …= %C%! , 2% !=“) 2 …=

.2%A ƒ=*=…),"= 2“ , C%C ! )…= =!A=23!= “2=",2“ ,ƒ *%…“2!3*- 2,"…/. “%%K!=› …,L.

j=* 3› %2A )=>%“@ !=… , ,=A 2! .%A32%" " " ƒ=…/. *=!- *=“=. ! *%A … 3 2“ C!,…,A=2@ … A … 5AA C!, "/“%2 K=>*,% 800 AA, = " K=>*=. K%>@H L "/“%2/O … A … 8AA.

o!, %2“32“2",, %2+,K%" …= 3)=“2*=. K=>*, "K>,ƒ, %C%! !=““2% …, A › 3 .%A32=A, “> 3 2 C!,…,A=2@ " “%%2" 2“2",, “ !,“. 12.

o!, …=>,),, %2+,K%" A%›…% 3" >,),2@ !=““2% …, A › 3

.%A32=A, …= C!,%C%!…/. 3)=“2*=. % 3/4h, …% … K%> , ) A 500 AA. b% "“ . “>3)= . !=““2% …, A › 3 .%A32=A, … %>›…%

C! "/H=2@ Smax.

e“>, 0,5bh0Rbt < Q, 2% !=“) 2 C%C ! )…%L =!A=23!/ C!%-%>›= 2“ …= 2 . 3)=“2*=. K=>*,, + .2% 3“>%", "/C%>… 2“ . o% “),2= A A=*“,A=>@…/L H=+ .%A32%"

bh2R

S = 0 bt max θ

, " “%%2" 2“2",, “ …%!A=A, …=ƒ…=),A !=““2% …, A › 3 .%A32=A,> C!,%C%!…/. , C!%> 2…/. 3)=“2*%" K=>*, (“A. !,“.12).

b =>@… LH A, ,ƒ *%…“2!3*2,"…/. “%%K!=› …,L ƒ= =E2“,=A 2!%A .%A32%" , ƒ=2 A C% “),2/"=E2

43

qsw = nswasw Rsw ≥ 0,25bRbt,

S1

+ CswO ),“>% “! ƒ%" .%A32=; bO H,!,…= ! K!= K=>*,; asw O C>%?= @ % …%L " 2", .%A32=; RswO !=“) 2…% “%C!%2,"> …,

.%A32=; Rbt O !=“) 2…% “%C!%2,"> …, K 2%…= …= !=“2 › …, , , => %C! > E2

Qbw +Qb +Qsw .

e“>, %*=› 2“ , )2% Qbw > Q, %2%+…32= =!A=23!= C% !=“) 23 … 2! K3 2“ , !=“) 2 …= .2%A ƒ=*=…),"= 2“ .e“>, › .2% 3“>%", … "/C%>… 2“ , 2% %C! > E2 C%C ! )…3E “,>3, *%2%!= %>›…= K/2@ "%“C!,… 2= %2+,K=A,:

" % …%L C>%“*%“2,, %C! > 2“ C% -%!A3>

p,“.17.j !=“) 23 %2%+…32%L =!A=23!/

44

+ α O 3+%> …=*>%…= %2+,K= A/. “2 !›… L * %“, K=>*,, %K/)…% C!,…,A= A/L !="…/A 450.

p=“) 2 %2%+…32/. “2 !›… L C!%,ƒ"% ,2“ " %C%!…/. “ ) …, . , " “ ) …, ., C!%.% ?,. ) ! ƒ …,›…, 2%)*, %2+,K%" (!,“. 17). q%%2" 2“2" ……% .2%A3 !=“) 23 " >,),…= C%C ! )…%L “,>/ Qs. inc %>›…= C!,…,A=2@“ !="…%L !=ƒ…%“2, " >,),… C%C ! )…%L

“,>/ 3 +!=…, %C%!/ , Qbw > %2+,K%" C !"%L C>%“*%“2, (“2 !›…, 1), = > %2+,K%" *=› %L ,ƒ C%“> 3E?,. C>%“*%“2 L (“2 !›…, 2 , 3)O !=ƒ…%“2, " >,),… C%C ! )…/. “,> 3 …,›…,. 2%) * C! / 3?,. (K%> K>,ƒ*,. * %C%! ) C>%“*%“2 L %2+,K%" , Qbw.

4.5. `! ,!%"=…, K= %* " ƒ=…/ , *=!*=“= ,

b ƒ=…/L *=!*=“ “%“2%,2 ,ƒ !=K%),. C!% %>@…/. “2 !›… L (C! A/. , %2%+…32/.), .%A32%" , A%…2=›…/. “2 !›… L. u%A32/

“>3)= ., *%+ = C% !=“) 23 %…, … 2! K3E2“ . l%…2=›…/ “2 !›…, “>3›=2 > C!,*! C> …, * …,A .%A32%" , > “%ƒ =…, *=!*=“=.

b ! ƒ3>@2=2 C%>3)= 2“ , )2% .2= =!A=23!= % …%"! A ……% "%“- C!,…,A= 2 %2!, =2 >@…/ %C%!…/ A%A …2/ (+%!,ƒ%…2=>@…/L 3)=“2%*) , C%C ! )…/ “,>/ (…=*>%……/L 3)=“2%* “2 !›… ). e“>, C>%?= , %2%+…32/. ,ƒ “A ›…/. C!%> 2%" “2 !›… L > "%“C!,- 2, %C%!…/. A%A …2%" %*=› 2“ … %“2=2%)…%, 2% " .2%A “>3)= …= %C%!%L “2=" 2 %C%>…,2 >@…/ “2 !›…, (“A. !,“. 18, “2 !›…, 6). e“>, › C>%?= @ C! A/. , %2%+…32/. ,ƒ "3. “%“ …,. C!%- > 2%" “2 !›… L %*=› 2“ K%>@H 2! K3 A%L C% !=“) 23, 2% )=“2@ %2%+…32/. “2 !›… L, !=“C%>%› ……/. K>,› * “ ! ,… C!%> 2=, … …3›…% 2 …32@ % %C%!/, = A%›…% ƒ=*%…),2@ ,. … K%>@H,A

45

+%!,ƒ%…2=>@…/A 3)=“2*%A >,…%L 20ds " !=“2 …32%L ƒ%… , 10ds " “›=2%L ƒ%… (“A.!,“.18, “2 !›…, 3).

p,“.18.q. A= =!A,!%"=…, +>="…%L K=>*, " ƒ=…/A, *=!*=“=A,

n2%+…32/ ,ƒ C!%> 2%" , %C%>…,2 >@…% C%“2="> ……/ …= %C%!=A, C! A/ “2 !›…, C% A ! 3A …@H …, %2!, =2 >@…/. A%A …2%" A%+32 K/2@ %K%!"=…/. o!, .2%A %K!/" %>› … %2“2%- 2@ %2 “ ) …, , " *%2%!%A “2 !› …@ C% !=“) 23 … 2! K3 2“ , …= !=““2% …, … A … W ( >,…= =…* !%"*,) , "% "“ *%A “>3)= … A … 20ds. g…=) …, W %C! > 2“ C% -%!A3>

+ QO C%C ! )…= “,>= " 2%)* 2 %! 2,) “*%+% %K!/"=;

46

As inc Rsw sin α O C%C ! )…= “,>=, "%“C!,…,A= A= %2+,K=A, " 2%A

› A “2 .

t%!A3>= (28) C%>3) …= ,ƒ 3“>%", C!%)…%“2, K=>*, C% *%- “%A3 “ ) …,E.

nK!/" “2 !›… L , A “2= %2+,K%" " %K? A “>3)= %>›…/ …=ƒ…=)=2@“ " “%%2" 2“2",, “ .CE!=A, ,ƒ+,K=E?,. A%A …2%" , C%C ! )…/. “,>. d> .2%+% …= =!A=23!…%A ) !2 › K=>*, “2!%,2“ .CE!= A=2 !,=>%", C! “2="> E?= “%K%L .CE!3 A%- A …2%" Ms, *%2%!/ A%› 2 "%“C!,… 2@ K=>*= C!, ,A E? A“ *%>,) “2" =!A=23!/.

d> C%“2!% …, .CE!/ A=2 !,=>%" A%›…% C%>@ƒ%"=2@“ “> 3E?,A, -%!A3>=A,:

=) …= 3)=“2*=. C%>%›,2 >@…/. A%A …2%"

+ η O 2=K>,)…/L *%.--, , …2, %C! > A/L C% -=*2,) - “*%A3 C!% …23 =!A,!%"=…, μ %. o!,K>,› ……% A%›…% C!,- … 2@ η = 0,85.

o!, C%“2!% …,, .CE!/ A=2 !,=>%" “),2=E2, )2% %2+,K= A/L “2 !› …@ ,“*>E)= 2“ ,ƒ !=K%2/ C%“2 C ……%, = %K!/"= A/LO " 2%)* 2 %! 2,) “*%+% %K!/"=, 2. . …= !=““2% …,, … A … W , … A … 20ds %2 -=*2,) “*%+% A “2= %K!/"= (!,“. 19).

Š=*,A %K!=ƒ%A, " K=>* C%“2% ……%+% “ ) …, .CE!= A=2 - !,=>%" K3 2 “%“2% 2@ ,ƒ +%!,ƒ%…2=>@…/. >,…,L, " !2,*=>@…/. 3“23C%" (" A “2=. %K!/"= “2 !›… L) , …=*>%……/. >,…,L (" A “2=. %2+,K= “2 !›… L).

`!A=23!3 “> 3 2 !=“C%>=+=2@ C% "%ƒA%›…%“2, !="…%A !- …% C% H,!,… “ ) …, K=>*, " % ,…, = ,…%+ = , " "= ! =. q> 3 2 ,ƒK +=2@ H=.A=2…%+% !=“C%>%› …, “2 !›… L " !.- … +% ! = %2…%“,2 >@…% …,›… +%, 2=* *=* C!, .2%A 2!3 …%“2,+…32@ 2?=2 >@…%+% ƒ=C%>… …, K 2%……%L “A “@E ƒ=ƒ%!%" A › 3 “2 !›… A,.

47

p,“.19.o%“2!% … .CE!/ A=2 !,=>%" K=>*,, =!A,!%"=……%L " ƒ=…/A, *=!*=“=A,

o!, !=“C%>%› …,, *%“/. (%2%+…32/.) “2 !›… L … %K.% ,A% “%K>E =2@ “> 3E?, *%…“2!3*2,"…/ 2! K%"=…, :

1) C !"/L %2+,K 3 “"%K% …%L %C%!/ %>› … …=),…=2@“ …=>@H 50 AA %2 +!=…, %C%!/ (!,“. 20,=), = 3 C!%A ›32%)…/.

%C%! … !=ƒ! ƒ…/. K=>%* … =>@H Smax (!,“. 20,K). h…%+ = > "/C%>… …, C%“> … +% 3“>%", C!,.% ,2“ “2=",2@ %C%>…,-

2 >@…/ *%“/ “2 !›…,;

2) !=““2% …, A › 3 …,›…,A *%… %A C !"%+% %2+,K= , …=- )=>%A "2%!%+% (" 2 . “>3)= ., *%+ = %2+,K/ 2! K3E2“ C% !=“) 23) 2=*› … %>›…% C! "/H=2@ Smax;

p,“.20.p=“C%>%› …, %2+,K%" C% >,… K=>*,: = O *!=L… %C%!=; K O C!%A ›32%)…= %C%!=

48

3) %2+,K= A/ “2 !›…, ! *%A … 3 2“ !=“C%>=+=2@ …= !=““2%- …,, … A … 2ds %2 K%*%"/. +!=… L (ds O ,=A 2! %2+,K= A/. “2 !›… L). n2+,K=2@ “2 !›…,, !=“C%>%› ……/ … C%“! “2" ……%

3K%*%"/. +!=… L K=>*,, … ! *%A … 3 2“ ;

4)%2+,K= A/ “2 !›…, ! *%A … 3 2“ !=“C%>=+=2@ “,AA - 2!,)…% %2…%“,2 >@…% C!% %>@…%L %“, K=>*,.

o!, "/“%2 K=>*, K%> 700 AA 3 K%*%"/. +!=… L %>›…= K/2@ C! 3“A%2! …= *%…“2!3*2,"…= A%…2=›…= =!A=23!= ,=- A 2!%A … A … 10 AA (“A. !,“. 16). r“2=…%"*= .2,. “2 !›… L %K3“>%"> …= "%ƒA%›…%“2@E "%ƒ…,*…%" …, !=“2 +,"=E?,. 3“,- >,L %2 *!3) …, , = 2=*› > 3A …@H …, !=“*!/2, 2! ?,…. j!%A 2%+%, .2, “2 !›…, C!, =E2 K%>@H3E › “2*%“2@ "“ A3 =!A=23!…%A3 *=!*=“3.

49

5. opnejŠhpnb`mhe jnknmm h trmd`lemŠnb

5.1.n“…%"…/ *%…“2!3*2,"…/ 2! K%"=…, * C!% *2,!%"=…,A *% %……,

!=K%2=A?,. …= …2!= ?…% “›=2,

j%>%……/ C! …=ƒ…=) …/ > C% !›=…, › > ƒ%K 2%……%+% C ! *!/2, . a3 3), › “2*% “" ƒ=……/A, “ +>="…/A, K=>*=A,, %…, -=*2,) “*, C! “2="> E2 “%K%L “2%L*, !=A…%L *%…“2!3*-,,. o%.2%A3 " …,. " %K? A “>3)= "%ƒ…,*=E2 “›,A=E?, 3“,>, , ,ƒ+,K=E?, A%A …2/ , C%C ! )…/ “,>/. n …=*% C!, !="…/. C!%> 2=. +>="…/. K=>%* ,>, C!%> 2=., … ƒ…=),2 >@- …% %2>,)=E?,.“ !3+ %2 !3+=, “! …, *%>%……/ ! K!,“2%+% C ! *!/2, , *=* C!=",>%, ,“C/2/"=E2 … ƒ…=),2 >@…/L ,ƒ+,K , ,. C!=*2,) “*, A%›…% “),2=2@ …2!=>@…% “›=2/A,. `!A,- !%"=…, › > ƒ%K 2%……%L *%>%……/ %“3? “2"> 2“ “2 !›… "%L C!% %>@…%L =!A=23!%L , .%A32=A, (C%C ! )…%L =!A=23!%L). o%- C ! )…% “ ) …, …2!=>@…% “›=2/. › > ƒ%K 2%……/. *%>%…… ,A 2 %K/)…% -%!A3 *"= !=2=. p=ƒA !/ “ ) …,L *%>%…… “> 3 2 C!,…,A=2@ *!=2…/A 5 “A. l,…,A=>@…/ !=ƒA !/ C%C ! )…%+% “ ) …, *%>%…… ,ƒ A%…%>,2…%+% › > ƒ%K 2%…= 300]300 AA.

`!A,!%"=…, *%>%…… C!%,ƒ"% ,2“ “"=!…/A ,>, " ƒ=…/A, C!%“2!=…“2" ……/A, *=!*=“=A, (!,“. 21). d,=A 2! C!% %>@…%L =!A=23!/ C!,…,A= 2“ !="…/A 16#32 AA. k,H@ > %“%K% A%?- …/. *%>%…… C!,A … E2“ K%>@H, ,=A 2!/.

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

50