Experimental shear-friction tests on dowel type fastener timber

([SHULPHQWDOVKHDUIULFWLRQWHVWVRQGRZHOW\SHIDVWHQHUWLPEHUFRQFUHWHMRLQWV
$OIUHGR'LDV
06F
3K'6WXGHQW
&RLPEUD8QLYHUVLW\'HOIW
8QLYHUVLW\RI7HFKQRORJ\
DOIJGLDV#GHFXFSW
+HOHQD&UX]/1(&3RUWXJDO
6pUJLR/RSHV&RLPEUD
8QLYHUVLW\3RUWXJDO
-:*.XLOHQ'HOIW
8QLYHUVLW\RI7HFKQRORJ\7KH
1HWKHUODQGV
6XPPDU\
7KHHIIHFWLYHQHVVRIWLPEHUFRQFUHWHFRPSRVLWHV\VWHPVLVKLJKO\GHSHQGHQWRQWKHHIILFLHQF\RIWKH
MRLQWV2QHRIWKHPRVWZLGHO\XVHGW\SHRIMRLQWLVWKHGRZHOW\SHIDVWHQHU0DQ\DVSHFWVRILWV
EHKDYLRXUKRZHYHUDUHQRWFRPSOHWHO\XQGHUVWRRG\HWSDUWLFXODUO\VRPHVHFRQGDU\HIIHFWV7KLV
SDSHUSUHVHQWVVRPHH[SHULPHQWDOVKHDUDQGIULFWLRQWHVWVSHUIRUPHGDW'HOIW8QLYHUVLW\RI
7HFKQRORJ\WRVWXG\VRPHRIWKRVHDVSHFWVQDPHO\WKHLQIOXHQFHRIWKHWKUHDGW\SHDQGIULFWLRQ
EHWZHHQWLPEHUDQGFRQFUHWH7KHIDVWHQHUVXVHGRQWKHVKHDUWHVWVKDGGLIIHUHQWFKDUDFWHULVWLFV
QDPHO\WKUHDGVVWHHOJUDGHDQGGLDPHWHUZKLOHWKHIULFWLRQWHVWVSHFLPHQVKDGWKHVDPH
FRQILJXUDWLRQDVWKHVKHDUWHVWVEXWZLWKRXWIDVWHQHUV6SHFLILFPHDVXUHPHQWVZHUHWDNHQLQRUGHUWR
HYDOXDWHWKHLQIOXHQFHRIFODPSLQJDQGIULFWLRQRQWKHVKHDUVWUHQJWKDQGVWLIIQHVVRIWKHMRLQWVIRU
ERWKW\SHVRIWHVWV7KHWHVWVSHFLPHQVFKDUDFWHULVWLFVWKHVHWXSDQGWKHWHVWSURFHGXUHDUH
GHVFULEHGDQGWKHUHVXOWVSUHVHQWHGDQGHYDOXDWHG7KHDQDO\VLVRIWKHVHUHVXOWVKDVVKRZQWKDWWKH
LQIOXHQFHRIWKHWKUHDGW\SHDQGIULFWLRQWLPEHUFRQFUHWHRQWKHEHKDYLRXURIWKLVW\SHRIMRLQWVLVRI
JUHDWLPSRUWDQFH
,QWURGXFWLRQ
2QWKHPHFKDQLFDOEHKDYLRXURIWLPEHUWRFRQFUHWHMRLQWVVRPHVHFRQGDU\HIIHFWVVXFKDVFKDLQ
HIIHFWVRUIULFWLRQEHWZHHQPDWHULDOVKDYHQRWZLGHO\EHHQVWXGLHG.XLSHUVDQG9DQGHU3XW>@KDYH
GHULYHGPRGHOVWRFDOFXODWHWKHFKDLQHIIHFWVLQWLPEHUWRWLPEHUMRLQWVZLWKVOHQGHUGRZHOW\SH
IDVWHQHUVXQGHUGLIIHUHQWFRQGLWLRQV7KRVHPRGHOVDUHEDVHGRQDQDQDO\WLFDOVWXG\DQGGHULYHG
FRQVLGHULQJGLIIHUHQWDVVXPSWLRQVWKDWPLJKWQRWEHUHDOLVWLFLQSUDFWLFDOFRQGLWLRQVRUIRUWLPEHUWR
FRQFUHWHMRLQWV7KHHTXDWLRQVSURSRVHGLQWKHUHYLVHGYHUVLRQIURP(&>@WRFDOFXODWHWKHORDG
FDSDFLW\RIWLPEHUWRWLPEHUMRLQWVKDYHDQLQGHSHQGHQWFRQWULEXWLRQWRFRQVLGHUWKHSXOORXW
VWUHQJWK,WDOORZVWKDWSDUWWREHXSWRRIWKHSXOORXWFDSDFLW\RIWKHIDVWHQHU6LQFHWKH
HTXDWLRQVIRUWLPEHUWRFRQFUHWHMRLQWVDUHEDVHGRQWLPEHUWRWLPEHUMRLQWVWKRVHPRGHOVDOVRDSSO\
IRUWLPEHUWRFRQFUHWH8VXDOO\WKHH[SHULPHQWDOUHVXOWVH[FHHGWKHYDOXHVHVWLPDWHGXVLQJWKH
PRGHOVZKDWFDQEHFDXVHGE\WKHHUURULQWURGXFHGE\QHJOHFWLQJVRPHVHFRQGDU\HIIHFWV,QRUGHUWR
HYDOXDWHWKHLPSRUWDQFHRIWKHVHSKHQRPHQDRQWKHPHFKDQLFDOEHKDYLRXURIWLPEHUWRFRQFUHWH
MRLQWVDQH[SHULPHQWDOUHVHDUFKZDVVWDUWHGLQ'HOIW8QLYHUVLW\RI7HFKQRORJ\7ZRGLIIHUHQWW\SHV
RIWHVWVZHUHSHUIRUPHGVKHDUWHVWVDQGIULFWLRQWHVWV7KHVKHDUWHVWVVXSSO\LQIRUPDWLRQDERXWWKH
PHFKDQLFDOEHKDYLRXURIWKHMRLQWVZKLOHWKHIULFWLRQWHVWVDUHXVHIXOWRHVWLPDWHWKHLPSRUWDQFHRI
IULFWLRQZKHQWLPEHUFRQFUHWHMRLQWVDUHORDGHGLQVKHDU8VLQJWKHVHUHVXOWVLWLVSRVVLEOHWRHYDOXDWH
WKHLQIOXHQFHRIFKDLQHIIHFWVDQGWLPEHUFRQFUHWHIULFWLRQRQWKHPHFKDQLFDOEHKDYLRXURIWKHMRLQWV
6KHDUWHVWV
7HVWVSHFLPHQVDQGWHVWVHWXS
7KHVKHDUWHVWVSHFLPHQVZHUHV\PPHWULFDOZLWKRQHFHQWUDOFRQFUHWHPHPEHUDQGWZRWLPEHUVLGH
PHPEHUVDOZD\VZLWKWKHVDPHVL]HV)LJXUH7KHSDUWRIWKHIDVWHQHULQVLGHWKHFRQFUHWHZDV
DOZD\VSODFHGLQVLGHDVPDOOSODVWLFWXEHRIPPWKLFNQHVVDQGDOHQJWKRIPP,QRUGHUWRDYRLG
DQ\PRYHPHQWRIZDWHUIURPWKHFRQFUHWHWRWKHWLPEHUDQGPLQLPL]HWKHIULFWLRQEHWZHHQERWK
PDWHULDOVDSODVWLFVKHHWZDVDOZD\VSODFHGEHWZHHQWKHWLPEHUDQGFRQFUHWH7KHWLPEHUXVHGZDV
JOXHGODPLQDWHGVSUXFHZLWKDPHDQGHQVLW\RINJP7KHFRQFUHWHKDGDYHUDJHFRPSUHVVLRQ
VWUHQJWKRI03D
/
'LVSODFHPHQW
)URQWDQGEDFN
/
'
7LPEHU
/RDG&HOO
7LPEHU
'
&RQFUHWH
/
'
'
PP
)LJ7HVWVHWXSFRQILJXUDWLRQDQGWHVWVHWXS
)LJ6SHFLDOIDVWHQHUDSSOLHGRQWKHWLPEHU
HOHPHQW
$OOWKHIDVWHQHUVZHUHLQVHUWHGLQKROHVZLWKDSUHGULOOHGGLDPHWHUHTXDOWRWKHVKDQNGLDPHWHURIWKH
IDVWHQHU7KUHHGLIIHUHQWIDVWHQHUVZHUHWHVWHGEDQGEMRLQWVZKLFKZHUHPDGHZLWKFRQFUHWH
UHLQIRUFHPHQWEDUVIURPWKHVWUHQJWKFODVV600DQG0ZKLFKZHUHODJVFUHZV6WHHO
JUDGHILQDOO\WKHWKLUGFRQQHFWRUZDVGHYHORSHGHVSHFLDOO\IRUWKLVSURMHFWDQGZDVPDGHIURP
VWHHOEROWVPDFKLQHGWRLQFUHDVHWKHWKUHDGVSDFLQJDQGWKLFNQHVV7KH
REMHFWLYHZDVWKHPD[LPL]DWLRQRIWKHSXOORXWVWUHQJWKRIWKHIDVWHQHU$OOIDVWHQHUVKDGDOHQJWKRI
PPLQWKHFRQFUHWHDQGPPLQWKHWLPEHUVHH7DEOH7KHORDGZDVDSSOLHGWRDOOWKH
VSHFLPHQVDWDFRQVWDQWUDWHXQWLOWKHPD[LPXPORDGZDVDFKLHYHG'XULQJWKHWHVWVWKHVSHFLPHQV
ZHUHSODFHGRYHUF\OLQGHUVDQGIRUWKDWUHDVRQRQO\YHU\VPDOOKRUL]RQWDOORDGFRXOGEHPRELOL]HG
RQWKHP
Force (kN)
7HVW5HVXOWV
7KHW\SHRIIDLOXUHREVHUYHGZDVVLPLODUIRUDOOWKHWHVWVDQGLWZDVFDXVHGE\WHQVLRQFUDFNVLQWKH
FRQFUHWHPHPEHU$VDFRQVHTXHQFHIRUPRVWRIWKHWHVWVSHFLPHQVWKHPD[LPXPORDGYDOXHV
REWDLQHGZHUHVPDOOHUWKDQFRXOGEHH[SHFWHG7KDWSKHQRPHQRQKDGLQIOXHQFHLQWKHUHVXOWV
REWDLQHGGLUHFWO\LQWKHFDVHRIWKHORDGFDSDFLW\DQGLQGLUHFWO\LQWKHVOLSPRGXOXVGXHWRWKH
HVWLPDWLRQRIWKH)HVWEDVHGRQWKH)PD[LQDFFRUGDQFHZLWK(11HYHUWKHOHVVWKHUHVXOWV
SUHVHQWHGRQ7DEOHLQGLFDWHWKDWWKHMRLQWVZLWKWKHODUJHUWKUHDGVVKRZEHWWHUPHFKDQLFDO
SHUIRUPDQFH7KHHIIHFWVKRXOGEHHYHQPRUHHYLGHQWLIWKHIDLOXUHZDVGXHWRHPEHGGLQJLQWLPEHU
ODUJHUVOLSLQVWHDGRIFUDFNVLQFRQFUHWH
,QWKHFDVHRI0DQG0
100
WHVWVPD[LPXPGLVSODFHPHQWV
90
RIDQGPPFRXOGEH
80
DFKLHYHGZKLOHIRUWKHRWKHU
E
70
MRLQWW\SHVWKHPD[LPXP
60
GLVSODFHPHQWVDUHRQO\IURP
E
WRPP7KHORDGFDUU\LQJ
50
FDSDFLW\GRHVQRWGLIIHUYHU\
40
PXFKIURPHDFKRWKHUH[FHSW
30
IRUWKHW\SH2QH
20
LPSRUWDQWSDUDPHWHUWR
10
HYDOXDWHWKHLPSRUWDQFHRI
0 0 0
FKDLQHIIHFWVLVWKHLQFUHDVHLQ
0
Slip 14
(mm)
0
2
4
6
8
10
12
16
WKHORDGDIWHUWKH\LHOGLQJRQ
WZRRIWKHWHVWVZLWKKLJKHU
)LJ/RDGVOLSFXUYHVRIWKHVKHDUWHVWV
YDOXHVRIPD[LPXPVOLS0
DQG0
7KHYDOXHVIRXQGRQWKRVHFDVHVDUHKLJKWKHLQFUHDVHRIWKHORDGDIWHUWKH\LHOGLQJZDVDURXQG
DQGRIWKHXOWLPDWHORDGUHVSHFWLYHO\7KLVPHDQVWKDWPRVWRIWKHORDGFDSDFLW\LVGXHWR
SKHQRPHQDWKDWRFFXUDIWHUWKH\LHOGLQJ&RPSDULVRQRIWKHVHUHVXOWVZLWKRWKHUUHVXOWVIURPWHVWV
SHUIRUPHGZLWKVPRRWKIDVWHQHUVVKRZVWKDWWKHORDGLQFUHDVHVDIWHU\LHOGLQJLVDOPRVWGRXEOHGLQ
WKLVFDVH>@7KHKRUL]RQWDOGLVSODFHPHQWEHWZHHQWKHWLPEHUVLGHPHPEHUVZHUHVLPLODUIRUDOOWKH
WHVWVSHUIRUPHG7KH\LQFUHDVHGDOZD\VLQWKHERWWRPDQGGHFUHDVHGDOPRVWDOZD\VLQWKHWRSWKLV
HIIHFWZDVKRZHYHUPXFKFOHDUHULQWKHVSHFLPHQVZLWKWKHODUJHUWKUHDGV2QWKRVHWKH
PHDVXUHPHQWVVKRZQRWRQO\WKDWWKHFRQWDFWDUHDZDVODUJHUEXWDOVRWKDWWKHGHIRUPDWLRQVDWWKDW
DUHDZHUHKLJKHU
7DEOH-RLQWFRQILJXUDWLRQVDQGWHVWVUHVXOWV
)DVWHQHUW\SH
E
E
0
0
0
6WHHO
'LDPHWHU 'LDPHWHU
6KDQNPP 1RPPP
6
6
1žRI
IDVWHQHUV
VKHDUSODQH
)PD[
NVHU
PD[VOLS
)ULFWLRQ7HVWV
7HVWGHVFULSWLRQ
7KHFKDUDFWHULVWLFVRIWKHIULFWLRQWHVWVSHFLPHQVZHUHWKHVDPHIURPWKHVKHDUWHVWVSHFLPHQV
)LJXUHEXWQRIDVWHQHUVZHUHXVHGRQO\DSODVWLFVKHHWZDVEHWZHHQWKHPDWHULDOV7ZR
KRUL]RQWDOIRUFHVZLWKWKHVDPHYDOXHZHUHSXWRQWKHVSHFLPHQDVLQGLFDWHGLQ)LJXUH)RUFH
OHYHOVRIN1ZHUHDSSOLHGE\HDFKORDGFHOO7KHFRQFUHWHPLGGOHPHPEHUZDV
WKHQSXVKHGRXWLQRUGHUWRHVWDEOLVKWKHIULFWLRQFRHIILFLHQWDWHDFKORDGOHYHO$WHDFKWHVWDQHZ
SODVWLFVKHHWZDVSODFHG7KHILQLVKLQJRIWKHVXUIDFHVZDVYHU\VPRRWKHLWKHUIRUFRQFUHWHRUWLPEHU
EHFDXVHWKHWLPEHUZDVSODQHGDQGWKHFRQFUHWHPHPEHUZDVFDVWDJDLQVWDSODVWLFVKHHWLQRUGHUWR
VLPXODWHH[DFWO\ZKDWKDSSHQHGLQWKHVKHDUWHVWV7KHWZRKRUL]RQWDOORDGVZHUHDSSOLHGLQVPDOO
VWHSVRQWKHXSSHUDQGERWWRPVLGHLQDZD\WKDWWKHORDGLQFUHDVHGVORZO\DQGZLWKDVLPLODUUDWHRQ
WRSDQGERWWRP$IWHUWKHLQWHQGHGKRUL]RQWDOORDGZDVFRPSOHWHO\DSSOLHGWKHVSHFLPHQZDVORDGHG
LQYHUWLFDOGLUHFWLRQVLPLODUO\DVLQWKHVKHDUWHVWV7KHORDGZDVDSSOLHGDWDFRQVWDQWUDWHXQWLOWKHUH
ZDVDQLQFUHDVHRIWKHVOLSZLWKDVPDOOFKDQJHLQWKHORDGLQSUDFWLFHWKDWKDSSHQHGIRUDVOLS
VPDOOHUWKDQPP
7KHORDGFHOOV/DQG/JDYHWKHYDOXHRIWKHKRUL]RQWDOIRUFHVLQWKHERWWRPDQGLQWKHWRSRIWKH
WHVWVSHFLPHQ7KHORDGFHOO/DQGWKHGLVSODFHPHQWJDJH'PHDVXUHGWKHYHUWLFDOIRUFHDQG
GLVSODFHPHQWZKLFKZHUHODWHUXVHGWRFDOFXODWHWKHVWDWLFIULFWLRQIRUFH7KHKRUL]RQWDO
GLVSODFHPHQWVPHDVXUHGRQ'WR'ZHUHXVHGWRFKHFNWKHPRYHPHQWLQWKHLQWHUIDFHRIERWK
PDWHULDOVDQGDIWHUZDUGVHVWDEOLVKDUHODWLRQEHWZHHQWKHVHUHVXOWVDQGWKHVKHDUWHVWVZLWKWKHGRZHO
W\SHIDVWHQHUV)LJXUH
5HVXOWVIURPWKHIULFWLRQWHVWV
7KHORDGVOLSEHKDYLRXUIRUWKHGLIIHUHQWORDGOHYHOVZDVTXLWHVLPLODUDOOWKHWHVWVVKRZHGWKHVDPH
HODVWLFEHKDYLRXUXQWLOWKHVOLSVWDUWHGWREHQRWLFHGDIWHUWKDWWKHEHKDYLRXURIWKHIULFWLRQZDV
DOPRVWSHUIHFWO\SODVWLFDVFDQEHVHHQRQ)LJXUH7KHYDOXHVIURPWKHIULFWLRQIRUFHVDQG
FRHIILFLHQWVZHUHFDOFXODWHGIURPWKHYDOXHVPHDVXUHGDWWKDWSRLQWDQGDUHSUHVHQWHGRQ7DEOH
7KHDYHUDJHYDOXHRIWKHIULFWLRQWLPEHUFRQFUHWHZDVIRXQGWREHZLWKDPD[LPXPYDOXHRI
DQGDPLQLPXPRI1RLQIOXHQFHZDVIRXQGIURPWKHQRUPDOIRUFHRQWKHYDOXHRIWKH
FRHIILFLHQWRIIULFWLRQ7KHVHUHVXOWVWRJHWKHUZLWKWKHYDOXHVRIWKHKRUL]RQWDOUHODWLYHPRYHPHQW
PHDVXUHGLQWKHVKHDUWHVWVLQGLFDWHWKDWWKHIULFWLRQWLPEHUFRQFUHWHPD\KDYHLPSRUWDQFH
VSHFLDOO\ZLWKMRLQWVZLWKWKUHDGVRQWKRVHFDVHVWKHFRQWDFWVXUIDFHGXULQJWKHWHVWLVELJJHUDQGWKH
IULFWLRQIRUFHVDUHKLJKHU
(kN)
Vertical force vs displacement
25
7DEOH)ULFWLRQWHVWUHVXOWV
20
+RUIRUFH
N1
15
×
×
×
×
×
×
×
×
×
×
10
5
0
0
0,5
1
1,5
2
2,5
(mm) 3
)LJ9HUWLFDOORDGYHUVXVGHIRUPDWLRQIRUIULFWLRQWHVWV
)ULFWLRQ
)RUFH &RHIILFLHQW
N1
$YHUDJH
&RQFOXVLRQV
7KHPHFKDQLFDOEHKDYLRXURIWLPEHUWRFRQFUHWHMRLQWVLVLQIOXHQFHGE\WKHW\SHRIWKUHDG)DVWHQHUV
ZLWKHQODUJHGWKUHDGVVHHPWRUHVXOWLQMRLQWVZLWKKLJKHUYDOXHVRIORDGFDSDFLW\DQGVOLSPRGXOXV
7KHLQFUHDVHLQWKHORDGFDUU\LQJFDSDFLW\DIWHU\LHOGLQJFDPHLQOLQHZLWKWKDWEHFDXVHWKH\DUH
PXFKKLJKHUIRUIDVWHQHUVZLWKWKUHDGWKDQIRUIDVWHQHUVZLWKRXWLW
7KHPHDVXUHPHQWVRIWKHKRUL]RQWDOGLVWDQFHEHWZHHQWLPEHUVLGHPHPEHULQGLFDWHWKDWWKHUHLV
FRQWDFWEHWZHHQWLPEHUDQGFRQFUHWHGXULQJWKHVKHDUWHVWVZKLFKLQFUHDVHVZLWKWKHSXOORXW
FDSDFLW\RIWKHIDVWHQHU)ULFWLRQEHWZHHQWLPEHUDQGFRQFUHWHRQWKHVHVSHFLILFFRQGLWLRQVWKURXJK
SODVWLFVKHHWKDVVKRZQWREHDQHODVWLFSODVWLFSKHQRPHQRQ7KHFRHIILFLHQWRIIULFWLRQZDVIRXQG
WREH7KHYDOXHVRIIULFWLRQWRJHWKHUZLWKKRUL]RQWDOGLVSODFHPHQWVPHDVXUHGLQWKHVKHDUWHVWV
VHHPWRLQGLFDWHWKDWWKHIULFWLRQWLPEHUFRQFUHWHKDVDQLQIOXHQFHRQWKHORDGFDUU\LQJFDSDFLW\DQG
WKDWWKHLQIOXHQFHLVKLJKHUIRUIDVWHQHUVZLWKODUJHUWKUHDGGLDPHWHUV
&RQVLGHULQJWKHVHHIIHFWVRQWKHFDOFXODWLRQPRGHOVZLOOOHDGWREHWWHUVLPXODWLRQVRIWKHUHDO
EHKDYLRXUDQGWRFORVHUDSSUR[LPDWLRQIURPWKHUHVXOWVREWDLQHGLQWKHH[SHULPHQWVIRUVWLIIQHVVEXW
VSHFLDOO\IRUORDGFDSDFLW\
$FNQRZOHGJHPHQWV
7KHDXWKRUVZRXOGOLNHWRWKDQN0U+\ONH.DWVPDIRUWKHSUHSDUDWLRQRIWKHWHVWVHWXSDQGWKH
GHYHORSPHQWRIWKHVSHFLDOVFUHZ
5HIHUHQFHV
>@ .XLSHUV-YDQGHU3XW7$&0%HWUDFKXQJHQ]XP%UXFKPHFKDQLVPXVYRQ
1DJHOYHUELQGXQJHQ,QJHQLHUKRO]EDXLQ)RUVKXQJXQG3UD[LV%UXGHUYHUODJ.DUOVUXKHSS
>@
&(1³SU(1'HVLJQRIWLPEHUVWUXFWXUHV3DUW´)LQDO'UDIW
>@
'LDV$YDQGH.XLOHQ-:&UX]+0HFKDQLFDOSURSHUWLHVRIWLPEHUFRQFUHWH
MRLQWVPDGHZLWKVWHHOGRZHOVWK&,%:&RORUDGR