Ukuhlaziywa lwemishayo phezu kuka. Kuka esiphezulu ugongolo: ifomula

Beam - elementi ubunjiniyela senduku okuyinto zithwesiwe amabutho senze isiqondiso perpendicular induku. Imisebenzi onjiniyela ngokuvamile kuhilela isidingo ukubala kuka ugongolo ngaphansi komthwalo. Lesi senzo wenziwa ukuze anciphise kuka esiphezulu ugongolo.

izinhlobo

Kuze kube manje, ukwakhiwa ingasetshenziswa imishayo ezenziwe ngezinto ezahlukene. Lokhu kungaba noma ukhuni. Icala elinye nelinye kusho ugodo ezahlukene. Ukubala lwemishayo phezu kuka angase abe umehluko ukuthi kuphakama ngesisekelo umehluko isakhiwo futhi izinto zokwakha.

imishayo yokhuni

ukwakhiwa ngabanye wanamuhla kusho ukusetshenziswa imishayo okwandile ezenziwe ngokhuni. Cishe wonke wokwakha iqukethe izibuya okhuni. Imishayo izinkuni ingasetshenziswa njengoba izakhi ukuzala, bajwayele ngesikhathi womshini iphansi, kanye isekela i slabs phakathi izibuya.

Kuyinto imfihlo ukuthi ukhuni, kanye steel ugongolo, ivame ukuba ehle bedle amabutho ukucindezeleka. kuka Umcibisholo kuxhomeke kulokho impahla isetshenziswa, lo weJiyomethri design izici, lapho isigxobo isetshenziswa, kanye nesimo imithwalo.

Kumiswa kuka avumelekile ugongolo is kusukela izici ezimbili:

• Ukuhambisana kuka kanye namagugu kuvunyelwe.
• Kungenzeka ukusebenzisa isakhiwo, kucatshangelwa kuka.

Olwenziwe usakhiwa amandla futhi rigidity uvumele okungcono ngikwazise lokho umthwalo zingamelana isakhiwo ngesikhathi ukusebenza. Futhi, lezi izibalo uvumele ukwazi kahle ukuthi kuyoba kwesakhiwo izakhi ukusonteka esimweni ngasinye. Mhlawumbe akekho azophikisana neqiniso lokuthi izibalo enemininingwane kakhulu futhi kunembile - iyingxenye imisebenzi onjiniyela civil, kodwa wonke amagugu kudingekile ingabalwa usebenzisa eziningi amafomula izibalo amakhono ngokuzimela.

Ukuze wenze ukubala efanele ugongolo kuka, umuntu kumelwe futhi acabangele yokuthi ukwakhiwa umqondo rigidity namandla bangamathe nolimi. Ngokusekelwe idatha kusuka sibalo amandla, ungakwazi uqhubekele phambili ukubala ukuqina isihlobo. Kufanele kuqashelwe ukuthi ukubala ugongolo kuka - esinye sezici ebalulekile ukubala le ukuqina.

Nakani yokuthi lezi izibalo wena kungcono ukusebenzisa izibalo oluhlanganisiwe, asebenzise isikimu kunalokho elula. Iphinde Kunconywa nesilinganiso encane ngendlela enkulu. Ikakhulukazi uma izakhi ukukhathazeka ukubala yenethiwekhi.

Ukuhlaziywa lwemishayo phezu kuka. algorithm

Eqinisweni, i-algorithm ngawo wenza ukubala efanayo ulula. Njengoba isibonelo, cabangela imininingwane ehilelekile umdwebo lula ukucabanga, ngaleyo ndlela sokukhipha amatemu ethize kanye namafomula. Ukuze abale kuka imishayo ku, enze izinyathelo ezilandelayo ukuze. I-algorithm sibalo okulandelayo:

• Ukubalwa isikimu senziwa.
• Ezimisele izici yejeyomethri ugongolo.
• Bala umthwalo esiphezulu kwi-elementi.
• Uma kwenzeka isidingo kuyaqinisekiswa amandla lezigodo eguqa okwamanje.
• Ubalisisa kuka esiphezulu.

Njengoba ubona, zonke izinyathelo kukhona kahle elula futhi ingenzeka.

Ukulungiselela ukubala isikimu imishayo

Ukuze wenze uhlelo ukubala, akudingi ulwazi oluningi. Kuyinto ngokwanele ukwazi ubukhulu kanye ukuma Ingxenye evundlile isici, span phakathi ezisekelweni indlela esindayo. Span kuyinto ibanga phakathi izisekelo ezimbili. Ngokwesibonelo, zisebenzisa ugongolo njengoba nemigoqo asekelayo kuyendlulela ukuzalela ezindongeni zendlu, phakathi kwabo 4 m, ukubaluleka span kuyoba ulingana 4 m.

Kubalwa kuka ugodo zokhuni ezincane, aqala ezibhekwa nje asekelwe izakhi eklanywe ngokuhlakanipha ngayo. Endabeni imishayo phansi sokubalwa ethathwa umthwalo wesifunda kwasakazwa ngokulinganayo. It ezikhonjiswe le q uphawu. Uma umthwalo egcinwe igxile ezintweni zemvelo, ukuthi ethathwa kanzulu umthwalo wesifunda, okhonjiswe F. ubukhulu lo mthwalo ilingane isisindo, okuzokwenza acindezele isakhiwo.

mzuzu inertia

izici e-Jomethri, ngokuthi mzuzu inertia, kubalulekile izibalo phezu kuka ugongolo. Ifomula ikuvumela ukubala lesi silinganiso, sikunikeza ke waba.

Lapho kubalwa mzuzu inertia kuyadingeka ukuba banake yokuthi ubukhulu lesi sici kuxhomeke kulokho orientation kwalesi sakhi isikhala. Ngakho kukhona lobudlelwano phakathi okwamanje inertia lokunyathelisa nenani kuka. I ezincane ukubaluleka mzuzu inertia, aba maningi ukubaluleka kuka futhi okuphambene nalokho. Lokhu kwencika Kulula kakhulu ukulandelela practice. Wonke umuntu uyazi ukuthi ibhodi, babeka onqenqemeni, flexes kancane kakhulu kunalokho ibhodi efanayo, okuyinto ngendlela evamile.

Ukubala mzuzu inertia okwesikhathi bukhanye unxande kwesigaba isiphambano ifomula:

J = b * h ^ 3/12 lapho:

b - ububanzi Sectional;

h - ukuphakama kwesigaba uvumelanise.

Bala esiphezulu umthwalo ezingeni

Icacisa umthwalo esiphezulu ku ilungu kwesakhiwo ekhiqizwa ikhumbula ezicini eziningana namamethrikhi. Ngokuvamile lapho kubalwa ezingeni umthwalo kucatshangelwa isisindo 1 imitha imishayo, isisindo 1 square imitha ophahleni, ophahleni umthwalo kanye nesimo okwesikhashana umthwalo kusukela izindonga 1 square imitha ophahleni. Futhi uyakucabangela ibanga phakathi imishayo kukalwa ngamamitha. Ngokwesibonelo, ekubaleni umthwalo esiphezulu ku ugodo lokhuni ukuthatha kumanani esilinganiso, owawuthi isisindo ukugqagqana kg 60 / m², zesikhashana ophahleni mthwalo 250 kg / m², ngodonga uyocabangela 75 kg / m². Isisindo ugongolo silula ukubala, ukwazi umthamo yayo kanye kwabantu. Ucabange ukuthi wasebenzisa lokhuni ugongolo kwesigaba 0,15h0,2 m. Kulokhu, isisindo sayo kuyoba 18 kg / egijima imitha. Futhi isibonelo, awathathe ibanga phakathi kokuncishiswa yokuntwela 600 mm. Kulokhu isilinganiso obudingekayo 0.6 kithi.

Ngenxa yalokho kokubala Isisindo esikhulu sithola umphumela elandelayo: q = (60 + 250 + 75) * 0,6 + 18 = 249 kg / m.

Lapho ukubaluleka etholwe, kungenzeka ukuhambisa sibalo kuka esiphezulu.

Kubalwa ukubaluleka kuka esiphezulu

Lapho sibona ugongolo, ifomula ubonisa zonke izakhi ezidingekayo. Kumele kukhunjulwe ukuthi ifomula osetshenziselwa ukubala, angase abe nombono ethé ukuhluka kancane, uma ukubala Kwenziwa yezinhlobo ezahlukene imithwalo, okuzokwenza sinomthelela ugongolo.

Okokuqala sikunikeza ifomula esetshenziswa ukubala kuka esiphezulu imishayo yokhuni nge umthwalo basakaza.

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

Qaphela ukuthi kule formula, E - owenziwa njalo, ebizwa ngokuthi wemfihlo nokunwebeka material. Zibe yizinkuni, lesi sibalo 100 000 kg / m².

Eqhubeka idatha yethu ukubala wasebenzisa isibonelo, sithola ukuthi, ngokuba yokuntwela ukhuni, esigabeni kabani ISIPHAMBANO m 0,15h0,2 nobude 4 m, inani kuka esiphezulu lapho sesimeni umthwalo basakaza ilingana 0.83 cm.

Sicela wazi ukuthi uma ekhiqizwa kuka ukucabanga ikhumbula circuit nge umthwalo kanzulu, ifomula kuthatha ifomu elandelayo:

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

F - amandla kwengcindezi ugodo.

Futhi banake yokuthi ukubaluleka kwengosi kuba wemfihlo okunwebeka lisetshenziswe izibalo ingahluka izinhlobo ezahlukene izinkuni. Wathonywa hhayi kuphela uhlobo ukhuni, kodwa futhi uhlobo lwemithi. Ngakho-ke, wonke ugongolo izinkuni, laminated yokwakha yaseGrisi imithi izingodo round kuyodingeka moduli ezahlukene kuyaqina, kanye namanani yingakho ezahlukene kuka esiphezulu.

Ungakwazi siphishekela imigomo ehlukile, okwenza ukubala imishayo e kuka. Uma ufuna ukwazi ukulinganiselwa ukusonteka of timphawu tesakhiwo, ke ekupheleni ukubala kuka umcibisholo, ungayeka. Uma umgomo wakho - ukusungula ababambisana nemithetho wathola izinkomba kwezokwakha, kumele ayeqhathanisa ngedatha, okuyinto ezibekwe imibhalo ekhethekile bemvelo normative.

I-ugongolo

Sicela uqaphele ukuthi girders mina-ugongolo asetshenziselwa kancane njalo ngenxa isimo sabo. Kodwa futhi ungakhohlwa ukuthi isici design onjalo zingamelana umthwalo okukhulu kunalokho endaweni noma isiteshi, okungaba esikhundleni mina-ugongolo.

Ukubalwa kuka H-ugongolo imele ukwenza kwenzeka ukuthi uyangena ukuyisebenzisa njengoba umklamo isici esinamandla.

Sicela uqaphele ukuthi akuzona zonke izinhlobo we girders mina-ugongolo ungakwazi ukubala kuka. Nokho, kwezinye izimo, bavunyelwe ukubala kuka H-ugongolo? Kuzo zonke izimo ezinjalo 6, okuyinto zivumelana eziyisithupha izinhlobo mina-imishayo. Lezi zinhlobo zimi kanje:

• Thayipha olulodwa-span bukhanye umthwalo nombala basakaza.
• Console Ngesandla Esiqinile esishunyekiwe ngakolunye uhlangothi nombala basakaza umthwalo.
• Ugongolo komunye span-console ngesandla esisodwa, okuyinto lisetshenziswa umthwalo nombala basakaza.
• uvumelanise Single ngohlobo lomnyango lokubizwa ngebutho kanzulu.
• Single-span nje asekelwe bukhanye amabutho amabili kanzulu.
• Console nge Ukuvalwa eqinile force kanzulu.

metal imishayo

Ukubala of kuka esiphezulu okufanayo, kungakhathaliseki ukuthi ugongolo steel noma i-elementi elinama ezahlukene. Into esemqoka - khumbula lezo zindinganiso ukuthi zisho okuthile ngokuqondile futhi unomphela, efana isibonelo wemfihlo we kuyaqina. Lapho besebenza zensimbi imishayo, kubalulekile ukukhumbula ukuthi zingenziwa ngensimbi noma i Mina-ugongolo. uvumelanise kuka metal ezenziwe ngensimbi, ibalwa uma ucabangela ukuthi lo E njalo kulokhu 2 × 105Mpa. Zonke ezinye izinto, ezifana mzuzu inertia, zibalwa ngokwendlela algorithm kuchaziwe ngenhla.

Ukubala of kuka esiphezulu ugodo nge izisekelo ezimbili

Njengoba isibonelo, cabanga isikimu lapho ugongolo ku izisekelo ezimbili, futhi nalokho sisetshenziswa ngempoqo kanzulu at iphuzu ezingafanele. Kuze okwamanje yokusebenzisa ugodo amandla emgceni locondzile, kodwa ngaphansi kwethonya amabutho ishintshile ukubukeka kwayo futhi ngenxa yobunzima baba ijika.

Ake sithi XY indiza yiyona indiza wesimethri ugongolo ku izisekelo ezimbili. Zonke imithwalo esebenza ugongolo kule indiza. Kulokhu, iqiniso liwukuthi ijika etholwe ngenxa yebutho, uyophinde abe kulesi indiza. Lokhu ijika libizwa emgqeni nokunwebeka ugodo noma umugqa ugongolo kuka. Algebraically ukuxazulula ulayini nokunwebeka ugodo abale kuka ugongolo, ifomula zazo eqondiswa imishayo nge izisekelo ezimbili, kanje.

Kuka ngesikhathi z ibanga kusuka kwesokunxele ukwesekwa imishayo for 0 ≤ z ≤ a

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

Kuka ugongolo ku izisekelo ezimbili ngesikhathi z ibanga kusuka ukwesekwa kwesokunxele okwesikhathi ≤ z ≤l

f (z) = (- P * a ² * b ²⁾ / (6E * J * l ) * ( 2 * (LZ) / b + ( LZ) / a- (LZ) ³ / a + b ^2), lapho F - isicelo amandla, E - wemfihlo nokunwebeka indaba, J - umzuzwana Axial of inertia.

Endabeni ugodo amabili isekela mzuzu inertia ibalwa kanje:

J = b ₁ h ₁ ^3/12 lapho b ₁ futhi h ₁ - ububanzi nobude esigabeni cross ugongolo esetshenziswa, ngokulandelana.

isiphetho

Ekuphetheni, kumele kuphetfwe ukuthi samstoyatelno ukubala kuka esiphezulu ugongolo ezahlukene ulula. Njengoba kuboniswe kulesi sihloko, into esemqoka - ukwazi ezinye izici encike zezinto ezibonakalayo nezingokomoya weJiyomethri izici, futhi ukwenza izibalo on amafomula eziningana lapho ipharamitha ngamunye has incazelo yalo futhi ingathathwa angaqondi ukuthi kungani.