許溝(gou)大橋位于洛三高速公路k49+453.37~k49+946.51,三門峽義馬市近郊(jiao),該橋橋孔布(bu)置自東(dong)向西:9×20m+220m+4×20m,全長493.14m。由中鐵(tie)十一局集(ji)團(tuan)第一工(gong)程有(you)限公司施工(gong)建設。
該橋橋孔布置自東(dong)向(xiang)西(xi):9×20m+220m+4×20m,全長(chang)493.14m。主孔為等(deng)截面懸(xuan)鏈線箱形無鉸拱,截面為三室箱,拱軸系(xi)數m=1.543,凈跨徑(jing)L0=220m,凈矢(shi)高f0=40m,矢(shi)跨比f0/L0=1/5.5。拱上(shang)建(jian)筑為13-17.5m先張預(yu)應力混凝(ning)土空心(xin)板及雙柱式排架立柱,橋面連(lian)續,柱間設橫向(xiang)聯系(xi)。東(dong)西(xi)引橋為20m預(yu)應力混凝(ning)土空心(xin)板梁,橋面連(lian)續,下部為雙柱式墩臺(tai),基礎(chu)為鉆孔灌注(zhu)嵌巖樁。
該橋橋寬為(wei)24m,分上、下行(xing)(xing),單幅橋寬為(wei)12m(11+2×0.5m墻式護欄)。設(she)(she)計荷載為(wei):汽(qi)-超(chao)20,掛-120。主拱(gong)拱(gong)座(zuo)(zuo)為(wei)重(zhong)力(li)式基礎,置于樁基或完整砂巖上。上下行(xing)(xing)之間(jian)設(she)(she)3cm沉降縫,每個拱(gong)座(zuo)(zuo)混凝(ning)土(tu)(tu)量6000m以上,屬(shu)大體(ti)積混凝(ning)土(tu)(tu),采(cai)取基坑(keng)滿注,提高拱(gong)座(zuo)(zuo)背后土(tu)(tu)抗力(li);主拱(gong)拱(gong)箱采(cai)用C50混凝(ning)土(tu)(tu)。上、下行(xing)(xing)拱(gong)圈之間(jian)為(wei)加(jia)強聯(lian)結(jie),設(she)(she)6處聯(lian)結(jie)系。
許溝(gou)大(da)橋位(wei)于洛(luo)三高速公路(lu)k49+453.37~k49+946.51,三門(men)峽義馬市近郊,常窯水庫下(xia)游,跨(kua)越(yue)許溝(gou),溝(gou)中常年無水。溝(gou)槽內地(di)(di)勢(shi)較為(wei)平坦,表(biao)層為(wei)亞砂土(tu),下(xia)層為(wei)卵石(shi)層;兩(liang)岸地(di)(di)質較好,表(biao)層有0~3m的沖積亞砂土(tu)和(he)卵石(shi)層,下(xia)層為(wei)泥質粉砂與粉砂質泥頁(ye)巖互(hu)層。該地(di)(di)區最(zui)大(da)風(feng)力為(wei)20m/s,有霜期為(wei)180~240天。