Uhlalutyo ezinemiqadi echweliweyo yemisedare phezu aphambuke. Kuka liphezulu umqadi: ifomula

Beam - elementi kwe- ngentonga leyo egcwele imikhosi isenza kwicala aa Incopho ngentonga. Imisebenzi iinjineli Ngokufuthi kubandakanya imfuneko ukubala aphambuke umqadi phantsi komthwalo. Eli nyathelo lwenziwa ukuze anciphise kuka ubuninzi umqadi.

iintlobo

Ukuza kuthi ga ngoku, ukwakhiwa ingasetyenziswa imiqadi ezenziwe ngezinto ezahlukeneyo. Oku kunokuba yesinyithi okanye umthi. Kwimeko nganye ithetha umqadi eyahlukileyo. Ukubalwa ezinemiqadi echweliweyo yemisedare phezu aphambuke inokuba nomahluko ezivela ngenxa yokungafani kubume izinto ezisetyenzisiweyo.

imisebe yeplanga

zokwakha ngamnye Namhlanje kuthetha a imiqadi ukusetyenziswa ngokubanzi eyenziwe ngomthi. Phantse wonke isakhiwo iqulethe imigangatho ngamaplanga. ingasetyenziswa Imiqadi kweenkuni njengezinto ngokuzala, ukuba zisetyenziswa ngexesha nokuveliswa imigangatho, kwakunye axhase Iizilebhu phakathi imigangatho.

Yinto akukho mfihlakalo ukuba iinkuni, kwakunye beam sentsimbi, idla SAG yesifundo phantsi kweempembelelo imikhosi uxinezeleko. aphambuke Arrow kuxhomekeke ngokwezinto iyasetyenziswa, iimpawu zejiyometri uyilo, umqadi isetyenziswa apho, kunye nohlobo imithwalo.

Kuka avumelekile umqadi lithatyathwe zinto zimbini:

• Ukuthotyelwa aphambuke kunye nemilinganiselo yokwakha.
• Ithuba ukusetyenziswa kwesakhiwo, kuthathelwa ingqalelo aphambuke.

Kwenziwa ngethuba ulwakhiwo amandla nokoma kuvumela baqonde ngcono oko umthwalo ungakwazi ukumelana zokwakha ngexesha lo msebenzi. Kwakhona, ezi zibalo ukuba ukwazi kuya kuba kanye yintoni noshowo izinto deformation kwimeko nganye. Mhlawumbi akukho namnye uya uphikise ukuba izibalo enenkcukacha kwaye nolwazi oluchanileyo - kube yinxalenye imisebenzi iinjineli yoluntu, kodwa onke amaxabiso oluyimfuneko kubalwa ngokusebenzisa inani neefomula kunye izibalo nobuchule ngokuzimeleyo.

Ukuze wenze ubalo oluchanekileyo beam aphambuke, omnye kufuneka ithathele ingqalelo into yokuba ukwakhiwa ingcamango ngqongqo kunye namandla basenokuvana. Ngokusekelwe data ekubaleni lwamandla, ungenza ukuqhubeka ukubala ngakumbi ngumkhinkqi isalamane. Kufuneka kuqatshelwe ukuba ukubalwa beam aphambuke - enye izinto ezibalulekileyo ekubaleni ukuqina.

Nikelani ingqalelo yokuba ezi izibalo ngokwakho kubhetele ukusebenzisa izibalo ebaliwe, Asebenzisa kwisiskim kunokuba elula. Kwakhona Kucetyiswa kratya encinane ngendlela enkulu. Ingakumbi ukuba izinto ezixhalabisayo ukubala yenethiwekhi.

Uhlalutyo ezinemiqadi echweliweyo yemisedare phezu aphambuke. i algorithm

Enyanisweni, lo algorithm apho wenza ubalo efanayo ilula. Ngokomzekelo, cinga ezinye umzobo lula ukubala, ngaloo ndlela lisuswe amanye amagama athile kunye neefomula. Ukuze kubalwe le kuka imiqadi kwi, yenze la manyathelo alandelayo ukwenzela. I algorithm ye ekubaleni zilandelayo:

• Calculation scheme senziwa.
• Kumiselwa iimpawu zejometri ye umqadi.
• Bala bomthwalo kwi element.
• Kwimeko intswelo kuyaqinisekiswa amandla nemithi ukuvumela mzuzu.
• Computes kuka ubuninzi.

Njengoko ubona, onke amanyathelo baxomoloza ezilula yaye kuyenzeka.

Ukulungiselela sokubala scheme imiqadi

Ukuze wenze inkqubo ukubala, akunamsebenzi kufuna ulwazi kakhulu. Akwanelanga ukuba ukwazi ubukhulu kunye nokumila icandelo umnqamlezo element, ngangomolulo phakathi exhasa kunye nendlela lokuzala. Span ngumgama phakathi lisekela ezimbini. Umzekelo, usebenzisa umqadi njengoko imivalo axhasayo ziyadibana ngenxa ethwele iindonga zendlu, lowo 4 m phakathi, ixabiso ubude iya kulingana-4 m.

Kuhlaziywa kuka umqadi ube mnye ngomthi, ukuba zigqalwa nje inkxaso imiba yoyilo. Kwimeko imiqadi floor ekubaleni i iyathathwa umthwalo wesekethe abelwa ngokulinganayo. It luchazwa lo q isimboli. Ukuba umthwalo ebanjwe ezisembindini kwindalo, ukuba buyasuswa wesekethe umthwalo kanzulu, zibonakaliswe F. Ubukhulu lo mthwalo uyalingana ubunzima, nto leyo eza kubeka uxinzelelo phezu isakhiwo.

mzuzu inertia

iimpawu zejiyometri, ebizwa kwixesha inertia, kubalulekile kule izibalo phezu kuka umqadi. Ifomula ikuvumela ukuba ukubala eli xabiso, siya kulinika kancinane.

Xa kubalwa kwixesha inertia kuyimfuneko ukunikela ingqalelo into yokuba ubukhulu balo msebenzi kuxhomekeke koko orientation sakhi emajukujukwini. Ngenxa yoko kukho lobudlelwano phakathi mzuzu inertia kunye nobungakanani aphambuke. I encinane ixabiso mzuzu inertia, kokukhona ixabiso aphambuke and vice versa. Oku kuxhomekeka Kulula kakhulu ukuba track practice. Wonke umntu uyazi ukuba ibhodi, wabeka buthelezi, flexes ngaphantsi kakhulu nebhodi efanayo, leyo kwindawo eqhelekileyo.

Ukubala lo mzuzu inertia ukuba azive olubuxande kwicala esiphambanweni ifomula:

J = b * h ^ 3/12 apho:

b - ububanzi yecandelo;

h - ukuphakama icandelo umqadi.

Bala izinga bomthwalo

Ukumisela umthwalo ubuninzi kwi ilungu noshowo zavelisa kuthathelwe ingqalelo inani lezinto kunye zokubhala. Ngokuqhelekileyo xa kubalwa inqanaba umthwalo i kuthathelwa ingqalelo ubunzima 1 imitha imiqadi, ubunzima 1 square yophahla imitha, umthwalo uphahla kunye nohlobo okwethutyana umthwalo ukusuka iindonga kwi-1 square yophahla semitha. Kwakhona ithatha ingqalelo umgama phakathi Imiqadi ulinganiswa eemitha. Umzekelo, ukubala bomthwalo kwi ngomthi ukuthatha amaxabiso avareji, njengoko apho ubunzima ukudibana yi-60 kg / m², umthwalo uphahla sethutyana 250 kg / m², izahlulelo wayeza nobunzima 75 kg / m². Ubunzima umqadi ilula kakhulu ukubala, esazi umthamo wayo kunye mninzi. Ucinge ukuba kusetyenziswa umqadi icandelo 0,15h0,2 ngomthi m. Kulo mzekelo, ubunzima bayo bekuya kuba-18 kg / imitha esebenzayo. Kwakhona umzekelo cingela umgama phakathi ngemiqadi ukungqubana 600 mm. Kulo mzekelo umlinganiselo efunekayo 0.6 kuthi.

Ngenxa yoko yokubala bomthwalo sinokuyifumana isiphumo kulandelayo: q = (60 + 250 + 75) * 0.6 + 18 = 249 kg / m.

Xa ixabiso bakufumana, kunokwenzeka ukuba bafudukele ekubalweni aphambuke ubuninzi.

Nasekubaleni ixabiso le aphambuke eliphezulu

Xa abale umqadi, ifomula lubonisa zonke izinto eziyimfuneko. Kufuneka kukhunjulwe ukuba ifomula esetyenziswa ekubaleni, ukuze abe nembono eyahlukileyo kancinane, ukuba ubalo lwenziwa kwiintlobo ezahlukeneyo kwemithwalo, nto leyo eya kuba nefuthe umqadi.

Okokuqala sikunika Ifomula esetyenzisiweyo ukubala kuka ubuninzi imiqadi ngomthi kunye umthwalo ezisasaziweyo.

f = -5 * q * l ^ 4/384 * E * J.

Qaphela ukuba kule formula, E - oqhubekayo, ebizwa ngokuba modulus kwilastiki lo mbandela. Ibe ziinkuni, eli nani 100 000 kg / m².

Ukuqhubeka ngedatha yethu yokubala esetyenzisiweyo umzekelo, siya ukufika kwelo, ukuze imiqadi iinkuni, candelo lomnqamlezo m 0,15h0,2 ubude-4 m, isixa aphambuke eliphezulu xa siphantsi umthwalo asasazwa ilingana 0.83 cm.

Nceda uqaphele ukuba xa kuveliswa ukubalwa aphambuke kuthathelwa ingqalelo beesekethe umthwalo kanzulu, ifomula kuthatha uhlobo kulandelayo:

f = -F * l ^ 3/48 * E * J, apho:

F - amandla xi amaplanga.

Kwakhona sinikele ingqalelo into yokuba ixabiso modulus of luthambe ezisetyenziswa izibalo inokwahluka kwiintlobo ezahlukeneyo kweenkuni. Azachaphazela kuphela uhlobo kweenkuni, kodwa ke uhlobo amaplanga. Ngoko ke, yonke umqadi iinkuni, elaminethiweyo ngokwenene imithi iinkuni ngeenxa zonke ziya kuba moduli ezahlukeneyo luthambe, kunye neenqobo apha ezahlukeneyo aphambuke ubuninzi.

Uyakwazi asukele iinjongo ezahlukeneyo, ukwenza ukubalwa imiqadi kwi aphambuke. Ukuba ufuna ukwazi imida deformation lweziqalelo zezakhiwo, ngoko ekupheleni ekubaleni kuka iintolo, ungakwazi uyeke. Ukuba usukelo lwakho - ukuseka izinga lokuthotyelwa wafumana izalathi si zokunikwa kweekhowudi yokwakha, kufuneka azinakulinganiswa data, leyo babekwa amaxwebhu ezizodwa ezikumila emisiweyo.

I-msebe

Nceda uqaphele ukuba kwezixhaso I-beam zisetyenziswa alufane ngenxa isimo sabo. Kodwa musa ukulibala ukuba into enjalo uyilo unako ukumelana umthwalo omkhulu kakhulu indawo okanye isitishi, anokuba enye ukuya I-akhanya.

Ukubalwa aphambuke H-beam omiyo ukwenza kwimeko apho uza ukulusebenzisa njengento design enamandla.

Nceda uqaphele kwakhona ukuba zonke iindidi kwezixhaso I-beam nga ukubala aphambuke. Noko ke, kwezinye iimeko, bavunyelwe ukuba babale aphambuke H-phahla? Kuzo zonke iimeko ezinjengezi 6, leyo kunxibelelana iintlobo ezintandathu echweliweyo. Ezi ntlobo zezi zilandelayo:

• Chwetheza beam single-ubude kunye umthwalo ngokufanayo ezisasaziweyo.
• Console ziqinile efakelweyo kwelinye icala asasazwa ngokufanayo umthwalo.
• Nomqadi ubude ukuya console ngesandla mnye, olusetyenziswa umthwalo ngokufanayo ezisasaziweyo.
• beam eyodwa uhlobo njengehenjisi wokunikela nomkhosi wamandla.
• Single-span inkxaso nje obengenakuvuya nemikhosi ezimbini kanzulu.
• Console kunye nokuvalwa ngqongqo kunye namandla wamandla.

imiqadi metal

Ukubalwa kuka liphezulu enye, nokuba yinto umqadi ube mnye sentsimbi okanye elementi ngento eyahlukileyo. Eyona nto ibalulekileyo - khumbula ezo amaxabiso ukuba ethile kunye nokusisigxina, ezifana umzekelo modulus of luthambe. Xa usebenza ngemiqadi yesinyithi, kubalulekile ukukhumbula ukuba zibe zenziwe ngesinyithi okanye I-msebe. beam aphambuke metal ezenziwe ngentsimbi, ibalwa ucinga ukuba E rhoqo kule meko 2 × 105Mpa. Zonke ezinye izinto, ezifana mzuzu inertia, zibalwa ngokungqinelana ubuchule ezichazwe ngasentla.

Ukubalwa kuka ubuninzi umqadi ube ne lisekela ezimbini

Ngokomzekelo, cinga ulungiselelo apho umqadi phezu exhasa ezimbini, kunye noko lusetyenziswa amandla wamandla endaweni kwincopho ngokwesigqibo esicalanye. De kube mzuzu zokusebenzisa umqadi mandla umgca othe ngqo, kodwa ke phantsi kwempembelelo imikhosi uye watshintsha bembonakalo yayo ngenxa yobunzima waba igophe.

Masithi ukuba XY moya moya yolingano ye umqadi kwi lisekela ezimbini. Yonke imithwalo omele umqadi kulo moya. Kulo mzekelo, inyaniso kukuba kwigophe afunyenwe ngenxa bomkhosi, kuya kubakho kulo moya. Le kwigophe kuthiwa umgca elastic lwe umqadi ube mnye okanye umgca umqadi aphambuke. Algebraically ukusombulula i kumgca elastic ye umqadi ube mnye aze abale kuka umqadi, ifomula leyo zigxunyekwe imiqadi kunye lisekela ezimbini, ngolu hlobo lulandelayo.

Le aphambuke kwindawo z umgama ukusuka yemiqadi inkxaso ngasekhohlo 0 ≤ z ≤ a

F (z) = (P * a ² * b ²⁾ / (6E * J * l ) * ( 2 * z / a + z / BZ ³ / a ² * b)

Kuka umqadi kwi lisekela amabini z Umgama ukusuka inkxaso ngasekhohlo ukuba ≤l ≤ z

f (z) = (- P * a ² * b ²⁾ / (6E * J * l ) * ( 2 * (lz) / b + ( lz) / i- (lz) ³ / a + b ^2), apho F - basebenzisa amandla, E - modulus eneplastikhi umbandela, J - mzuzu yezihlunu of inertia.

Kwimeko umqadi ube ne ezimbini ixhasa mzuzu inertia ibalwa ngolu hlobo lulandelayo:

J = b ₁ h ₁ ^3/12 apho b ₁ h ₁ - nobubanzi, ukuphakama kwicandelo umnqamlezo umqadi esetyenzisiweyo, ngokulandelelana.

isiphelo

Xa ndiqukumbela, kunokwenziwa isigqibo sokuba samstoyatelno ubale aphambuke iphezulu msebe iintlobo ezahlukeneyo ilula. Njengoko kubonisiwe kweli nqaku, into engundoqo - ukwazi ezinye iimpawu ezixhomekeke eziphathekayo zejometri iimpawu, yaye benze izibalo kwi ifomula eziliqela apho parameter nganye ingcaciso yayo kwaye ethatyathwe ndawo.