1、自(zi)墩頂向兩側分段(duan)(duan)懸臂施工(gong)(gong)這是大跨(kua)徑橋梁掛藍施工(gong)(gong)常用(yong)(yong)的辦(ban)法，現將它運用(yong)(yong)到(dao)移(yi)動(dong)模(mo)架(jia)上(shang)來(lai)。其原理是利用(yong)(yong)連續梁自(zi)重(zhong)(zhong)彎(wan)(wan)(wan)(wan)矩(ju)有兩個(ge)反彎(wan)(wan)(wan)(wan)截(jie)面的特點，第一(yi)次先施工(gong)(gong)墩頂約(yue)0.5L負彎(wan)(wan)(wan)(wan)矩(ju)段(duan)(duan)（A塊），要(yao)求其自(zi)重(zhong)(zhong)產生(sheng)的彎(wan)(wan)(wan)(wan)矩(ju)小于移(yi)動(dong)模(mo)架(jia)容許(xu)彎(wan)(wan)(wan)(wan)矩(ju)，當(dang)A段(duan)(duan)箱梁澆注(zhu)完成(cheng)達到(dao)設(she)計強度并張拉預應力(li)束后(hou)，A塊從移(yi)動(dong)模(mo)架(jia)上(shang)脫(tuo)開(kai)，其自(zi)重(zhong)(zhong)所產生(sheng)的彎(wan)(wan)(wan)(wan)矩(ju)可(ke)由梁段(duan)(duan)自(zi)身所承(cheng)擔(dan)，其重(zhong)(zhong)量通過支座轉移(yi)到(dao)墩柱上(shang)。第二次模(mo)架(jia)不移(yi)動(dong)而僅僅滑(hua)動(dong)模(mo)板澆注(zhu)跨(kua)中（0.5L）正彎(wan)(wan)(wan)(wan)矩(ju)段(duan)(duan)（B塊），此時移(yi)動(dong)模(mo)架(jia)僅需承(cheng)擔(dan)正彎(wan)(wan)(wan)(wan)矩(ju)段(duan)(duan)（B塊）的重(zhong)(zhong)量。很明顯分二次澆注(zhu)與一(yi)次澆注(zhu)相比較，梁體對支架(jia)彎(wan)(wan)(wan)(wan)矩(ju)減少四倍，大大減少移(yi)動(dong)模(mo)架(jia)材料用(yong)(yong)量。

2、本工(gong)(gong)法采用的移動模架(jia)結構簡單，技術(shu)易(yi)于掌握，可(ke)實施(shi)流水作業；貝(bei)雷(lei)(lei)架(jia)通(tong)(tong)用性很強，屬(shu)施(shi)工(gong)(gong)單位常(chang)備器材。當不同(tong)的箱梁混凝土(tu)重量、箱梁頂板和底(di)板寬度(du)及跨度(du)變(bian)化時，通(tong)(tong)過調(diao)整(zheng)貝(bei)雷(lei)(lei)架(jia)的配置(zhi)片數等(deng)即(ji)可(ke)用于施(shi)工(gong)(gong)。