無(wu)梁拱屋面被(bei)廣泛用(yong)于工業廠房、倉儲(chu)庫(ku)房、無(wu)梁拱體(ti)育場館、集貿(mao)市場、車庫(ku)機庫(ku)等(deng)，它無(wu)梁無(wu)擦、空間高(gao)大(da)開闊，可以(yi)隨意分割組合，使用(yong)方便，自重輕、剛性強(qiang)、彈性好、抗震等(deng)特點。
無梁拱(gong),拱(gong)形屋(wu)面還具(ju)有承壓(ya)效(xiao)果(guo)，拱(gong)所承受的荷載(zai)(zai)不同(tong)，其壓(ya)力曲線的線形也不相同(tong)，一般按恒(heng)載(zai)(zai)下壓(ya)力曲線確定;在活載(zai)(zai)作(zuo)用(yong)下，拱(gong)內力可能產生彎(wan)(wan)矩(ju)，這(zhe)時鉸(jiao)的設置就會影響拱(gong)內彎(wan)(wan)矩(ju)的分(fen)布狀況。與剛架相仿，只有地基良好(hao)或兩(liang)側拱(gong)肢處有穩定邊(bian)跨結構時才采(cai)用(yong)無鉸(jiao)拱(gong)，這(zhe)種(zhong)拱(gong)很少用(yong)于房屋(wu)建(jian)筑(zhu)。雙鉸(jiao)拱(gong)應(ying)用(yong)較多，為適應(ying)軟弱地基上支座沉降(jiang)差及(ji)拱(gong)拉(la)桿(gan)變形，采(cai)用(yong)靜定結構的三鉸(jiao)拱(gong)。
拱(gong)(gong)(gong)(gong)(gong)以曲桿抗衡并傳遞外力(li)(li)(li)給(gei)支(zhi)座，故(gu)鉸支(zhi)座不僅(jin)承受(shou)豎向力(li)(li)(li)，并有相(xiang)當大的(de)(de)(de)水(shui)平向外的(de)(de)(de)拱(gong)(gong)(gong)(gong)(gong)腳推(tui)力(li)(li)(li)，其合力(li)(li)(li)就位(wei)于拱(gong)(gong)(gong)(gong)(gong)軸曲線(xian)在(zai)支(zhi)座點(dian)的(de)(de)(de)切(qie)線(xian)方向上。拱(gong)(gong)(gong)(gong)(gong)腳有推(tui)力(li)(li)(li)是(shi)其主要力(li)(li)(li)學特征之(zhi)一(yi)，矢高f越(yue)(yue)小，推(tui)力(li)(li)(li)越(yue)(yue)大。一(yi)次超靜定的(de)(de)(de)雙鉸拱(gong)(gong)(gong)(gong)(gong)，金屬屋(wu)面支(zhi)座的(de)(de)(de)垂直或水(shui)平位(wei)移均(jun)會引起內力(li)(li)(li)變(bian)化，對支(zhi)座在(zai)推(tui)力(li)(li)(li)作用下無變(bian)位(wei)的(de)(de)(de)要求(qiu)就更嚴格(ge)。由此可見，為(wei)了(le)使拱(gong)(gong)(gong)(gong)(gong)保持正常(chang)工作，務必確保其支(zhi)座能承受(shou)住推(tui)力(li)(li)(li)而不位(wei)移，故(gu)拱(gong)(gong)(gong)(gong)(gong)腳推(tui)力(li)(li)(li)的(de)(de)(de)結構(gou)處(chu)理，是(shi)拱(gong)(gong)(gong)(gong)(gong)結構(gou)設計的(de)(de)(de)中心問題(ti)。
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