Proiectarea Si Tehnologia Prelucrarii Lemnului Si a Produselor Finite Din Lemn
Proiectarea Si Calculul Lemnului 1rrr
Transcript of Proiectarea Si Calculul Lemnului 1rrr
-
8/20/2019 Proiectarea Si Calculul Lemnului 1rrr
1/10
-
8/20/2019 Proiectarea Si Calculul Lemnului 1rrr
2/10
-
8/20/2019 Proiectarea Si Calculul Lemnului 1rrr
3/10
-
8/20/2019 Proiectarea Si Calculul Lemnului 1rrr
4/10
INCO"OIERE#INCO"OIERE# SIMPLA SIMPLA
"ERIFICARE DE REZISTENTA#"ERIFICARE DE REZISTENTA# ) R( W
M i ai
net
σ σ ≤=
M @ )3 -3*-)' 3'& () *&*+; @ )3 -3*-)' 3'& () *&*+;
net W @ + ) ')7-)3& 3);@ + ) ')7-)3& 3);
i σ @ ')7-)3& &--.-& & -3*-)'); @ ')7-)3& &--.-& & -3*-)');
i R @ ')7-)3& ) *&*+ & -3*-)'); @ ')7-)3& ) *&*+ & -3*-)');
ATENTIE# &*& )*-+3)& *)& &- &.-& 3+ *-3*-) *+ )*-+3)& -3 *&')ATENTIE# &*& )*-+3)& *)& &- &.-& 3+ *-3*-) *+ )*-+3)& -3 *&')
)3+ -3*-)' )) &-$ ) -%+3) )'-,-*&')& ) )3+ -3*-)' )) &-$ ) -%+3) )'-,-*&')& )
')7-)3& - -3 )*-+3)& *+ &.-'- &-) ')7-)3& - -3 )*-+3)& *+ &.-'- &-)
"ERIFICARE DE RIGIDITATE#"ERIFICARE DE RIGIDITATE# EI
l M f max
2
α =
N'*'N'*' E))3E))3
S&)&& --&S&)&& --&
I3*&'*&'- )I3*&'*&'- )
+3& +'&&+3& +'&&I3*&'*&'- )I3*&'*&'- )
*+'& +'&&*+'& +'&&
11 P&3)) *+')3)P&3)) *+')3) L/250L/250 L/250L/250
22 P&3)) %P&3)) % L/200L/200 L/200L/200
A*%)'-+'-A*%)'-+'-
%&3)$ *&%'-'-; %&3)$ *&%'-'-;
&)')&&; &)')&&;L/200L/200
L/150L/150L/150L/150
L/100L/100
44 D--D-- L/400L/400 L/00L/00
I3 )3)'&$ %) &3& -3*-)') &%&') - ,',)*&')I3 )3)'&$ %) &3& -3*-)') &%&') - ,',)*&') ) R( bI
QS f a
b
bτ τ ≤=
Q @ ,'& &-)&') 3'&&@ ,'& &-)&') 3'&&
(*&*+;(*&*+;
b S @ )3+ &-* .'+ &@ )3+ &-* .'+ &
)*-+3--;)*-+3--;
b @ &-)& )*-+3--; @ &-)& )*-+3--;
b I @ )3 ) -3)'-) .'+@ )3 ) -3)'-) .'+)*-+3);)*-+3);
ATENTIE# )'-,-*&')& ))ATENTIE# )'-,-*&')& ))
3)*)&'& %)3'+ '-37- *+')3)*)&'& %)3'+ '-37- *+')
(/=>5(/=>5
OBLICAOBLICA
"ERIFICARE DE"ERIFICARE DE
REZISTENTA#REZISTENTA#
) R( W
M
W
M i ai
y
y
x
x
σ σ ≤+=
josdreapta
. gr cap M
dreapta
asociat Q
susstanga
. gr cap M
stanga
asociat Q
normatq
durata lunga p
susdreapta
. gr cap M
dreapta
asociat Q
josstanga
. gr cap M stangaasociat
Q
l1
-
8/20/2019 Proiectarea Si Calculul Lemnului 1rrr
5/10
"ERIFICARE DE RIGIDITATE#"ERIFICARE DE RIGIDITATE# adm y x f f f f ≤+= 22
COMPRESIUNE ECENTRICA (DREAPTA SI OBLICA
FORTA AIALA DE COMPRESIUNE (%) %7--) ),'&&;
MOMENT INCO"OIETOR ( x M
; sau ) M si M
y x
e N M M M ld I
calcul ⋅+∆+= +3)#
H S M I
⋅= ;;
I II
M M ⋅=η ;; I II M M M −=∆
cr
ld
N
N −
=
1
1η
$$( )
2
2
f
al convention
cr l
EI N
π = ;;
) R( W
M
W
M
A
N i ai
y
y
x
x
σ σ ≤±±=
Ipoteza III
calcul
x M
calcul
y M
N
Ipoteza I
calcul
x M
N
Ipoteza II
calcul
y M
N
X
Y
H
r
y
t
y y S S S +=
r
x x S S =
ld N
H S M y I
y ⋅=
X
Y
H
ld N
H S M y I
y ⋅=
H S M x I
x ⋅=
r
x
r
x
t
x x S S S S 21 ++=
r
y
r
y
t
y y S S S S 21 ++=
X
Y
r
x
t
x x S S S += r
y y S S =
H S M x I
x ⋅=
ld N
H
I%)7& I I%)7& II I%)7& III
-
8/20/2019 Proiectarea Si Calculul Lemnului 1rrr
6/10
SARPANTESARPANTE
TIPURI CONSTRUCTI"E SI ELEMENTE COMPONENTETIPURI CONSTRUCTI"E SI ELEMENTE COMPONENTE
SARPANTE DIN CAPRIORI# ALCATUIRE# %)')*=- ) *&%'-'- *+ &+ ,&'& -'&3-
'-73&- ) '---7&');
DESC!IDERE# 600 ,&'& -'&3-;
900 *+ -'&3-;
STABILITATEA GENERALA# *3'&&3+-'- 3;
SARPANTE PE SCAUNE# ALCATUIRE# )))3) )'-*&) (%%-;
)))3) '-73&)3-+ (%&3);
)))3) -3*-3&) (*&%'-'-;
)))3) '-73&) ) '---7&') '&3
)))3) -3*-3&) ) '---7&') '&3
STABILITATEA GENERALA# *3'& 3
-
8/20/2019 Proiectarea Si Calculul Lemnului 1rrr
7/10
!"I#N $N %$&%'&$(I)N
*)) spe+,al ,tems
'ser reu,rements - I") 2/118/ $N "($" 12/0085
sta,l,t4 and strengt 6rel,a,l,t4 +on,gurat,ons;
,re saet4; seal,ng;
HI#)(!9I%! !:'I!9!N(";
$I (!9!$('!;
$%)'"(I% !:'I!9!N(";
e +ur>,l,near nature;
*$NIN#? te s,z,ng ,s done ,n te +ond,t,on o res,stan+e;
- %ompressor 6parallel ,ersB;
+ompress,>e ea>,or;⇔- $d>erse ,mpa+t o dee+ts and @eaCen,ng ,s lo@er tan or
stret+,ng plast,+ t,mer
*$NIN#? te s,z,ng ,s done ,n general u+Cl,ng;
- =end,ng?
- ",mpl,4,ng assumpt,ons? D HooCe la@ =ernoull, 4potes,s;
- "tat,+ end,ng s+eme @,tout sear;
te e,gt o te +ross se+t,on;σ- ,str,ut,on o stresses
- %'"HIN# 6+ompress,on perpend,+ular to gra,nB;
sσ
- Aor Ep deormat,ons are elast,+ and are lo@ 6@ell-ea>ed +ell @allsB;σ
sσ- Aor F p deormat,ons are permanent and a>e ,g >alues 6destru+t,on o +ell @allsB;σ
-
8/20/2019 Proiectarea Si Calculul Lemnului 1rrr
8/10
sσ- Aor FF p gro@,ng stra,ns 6tamp,ng +ell @allsB;σ
pσ*$NIN#? te supports are not allo@ed ,n te reuests tat eG+eed
- "H!$?
t trans>erse sear strengt;τ- p parallel sear strengt;τ- perp perpend,+ular tens,le sear strengt;τ-
%$&%'&$(I)N spe+,al ,tems
*)) se+t,onal "I9&!
aG,al?θ N( normal,zed aG,al or+e 6+omput,ngB; Year +ross-se+t,onal area loosen;
at perm,ss,le tens,le strengt along te ,ers;σ t des,gn strengt o tens,on along te ,ers;
aG,al +ompress,on?θ %oe,+,ent o u+Cl,ng;
%r,t,+al u+Cl,ng strengt;
9odulus o elast,+,t4 o te mater,al;
9oment o ,nert,a o te se+t,on 6d,spers,on eG.>alor,B;
(e lengt o te u+Cl,ng o te ar 6per ear,ngB;
ad,us o g4rat,on;
"lenderness ,s uant,,ed 4 6slenderness rat,oB;
(o ota,n;
(o ota,n
Nr.+rt. Name element slenderness +oe,+,ent maG,mum adm,ss,le
%onstru+t,on de,n,t,>e temporar4 u,ld,ngs
1. trusses and ar+es
- Aeet d,agonal mull,ons and support
- )ter ,tems150
175
175
200
2. ma,n p,llar
120 se+ondar4 poles
150 150
175
3. =ra+,ng 200 200
end,ng?θ
-
8/20/2019 Proiectarea Si Calculul Lemnului 1rrr
9/10
- ",mple
#ross se+t,on stat,+ moment;
*,dt o se+t,on;
#ross moment o ,nert,a se+t,on;
$ttent,on?
%onstru+t,on t4pes and parts
-
8/20/2019 Proiectarea Si Calculul Lemnului 1rrr
10/10
"naCe deer - %ompos,t,on? pa,rs o raters @,t or @,tout t,e rods
or,zontal re,nor+,ng;
- )!NIN#? .00m @,tout t,e rods;
.00m @,t t4rants;
- )>erall sta,l,t4? long ra+,ng .;
Arame@orC on +a,rs - %ompos,t,on? >ert,+al elements 6propsB;
-&)N#I('! or,zontal elements.
6r,edB;
,n+l,ned elements 6ratersB;
trans or,zontal re,nor+,ng elements.
(rans>,t ,n+l,ned re,nor+,ng elements.
- )>erall sta,l,t4? %ontra>e. D (rans>,t long.
- (4pes? epend,ng on open,ng te pos,t,on element >ert,+al stru+tural 6@alls or ramesB;
oo truss element +omputat,ons
%H$#IN# #)'
- $""'9(I)N I? permanent load D sno@ load;
- $""'9(I)N II? permanent load D @,nd loads 6pressureB D
,n+ar+area o sno@;D- $""'9(I)N III? permanent load D +on+entrated load 61000NB;
- $""'9(I)N I