許溝大(da)橋(qiao)位于洛三高速公(gong)路k49+453.37~k49+946.51,三門峽義馬(ma)市(shi)近(jin)郊,該(gai)橋(qiao)橋(qiao)孔布置自東向(xiang)西(xi):9×20m+220m+4×20m,全長493.14m。由中(zhong)鐵十一(yi)局集團(tuan)第(di)一(yi)工程有限公(gong)司施(shi)工建設。
該橋(qiao)(qiao)(qiao)橋(qiao)(qiao)(qiao)孔布置自東(dong)向(xiang)西:9×20m+220m+4×20m,全(quan)長493.14m。主(zhu)孔為等截面懸鏈線箱(xiang)形無鉸拱(gong),截面為三(san)室箱(xiang),拱(gong)軸系數(shu)m=1.543,凈跨徑(jing)L0=220m,凈矢高f0=40m,矢跨比f0/L0=1/5.5。拱(gong)上(shang)建筑(zhu)為13-17.5m先張預應力混(hun)凝(ning)土空心板及雙(shuang)柱(zhu)式排架(jia)立柱(zhu),橋(qiao)(qiao)(qiao)面連續(xu),柱(zhu)間設橫向(xiang)聯系。東(dong)西引橋(qiao)(qiao)(qiao)為20m預應力混(hun)凝(ning)土空心板梁(liang),橋(qiao)(qiao)(qiao)面連續(xu),下部為雙(shuang)柱(zhu)式墩臺,基(ji)礎為鉆孔灌注(zhu)嵌巖樁(zhuang)。
該橋橋寬為24m,分上(shang)(shang)、下行,單幅橋寬為12m(11+2×0.5m墻式(shi)護欄)。設計荷載為:汽(qi)-超20,掛-120。主(zhu)拱(gong)拱(gong)座為重力式(shi)基礎,置于樁基或(huo)完整砂巖(yan)上(shang)(shang)。上(shang)(shang)下行之間(jian)設3cm沉降(jiang)縫,每個拱(gong)座混(hun)凝土(tu)量(liang)6000m以上(shang)(shang),屬(shu)大體(ti)積混(hun)凝土(tu),采(cai)(cai)取(qu)基坑滿注,提高拱(gong)座背后土(tu)抗力;主(zhu)拱(gong)拱(gong)箱采(cai)(cai)用C50混(hun)凝土(tu)。上(shang)(shang)、下行拱(gong)圈之間(jian)為加強聯結,設6處聯結系。
許(xu)溝(gou)(gou)大橋(qiao)位于洛三(san)(san)高(gao)速公(gong)路(lu)k49+453.37~k49+946.51,三(san)(san)門峽(xia)義馬市近(jin)郊(jiao),常(chang)窯水庫下(xia)游(you),跨越(yue)許(xu)溝(gou)(gou),溝(gou)(gou)中常(chang)年無水。溝(gou)(gou)槽(cao)內地(di)勢較為平(ping)坦,表層(ceng)(ceng)(ceng)為亞砂(sha)土(tu),下(xia)層(ceng)(ceng)(ceng)為卵石層(ceng)(ceng)(ceng);兩岸(an)地(di)質(zhi)較好,表層(ceng)(ceng)(ceng)有0~3m的(de)沖積亞砂(sha)土(tu)和卵石層(ceng)(ceng)(ceng),下(xia)層(ceng)(ceng)(ceng)為泥質(zhi)粉(fen)砂(sha)與粉(fen)砂(sha)質(zhi)泥頁巖互層(ceng)(ceng)(ceng)。該地(di)區(qu)最大風力(li)為20m/s,有霜期為180~240天(tian)。