介绍: 2.斜井总体施工方案 2.1选择位置依据 ⑴增加斜井后能确实有效地缩短工期。 ⑵有较好的施工用水、用电等外部环境。 ⑶有较好的施工条件、场地及弃渣用地。 ⑷设置斜井的位置尽量少占用场地,避免拆迁。 ⑸斜井的选线尽量避免房屋建筑,以减少施工干扰。 ⑹经济合理的原则。 基于以上原则,对xx隧道全线进行了详细的勘察、对比,最终决定将斜井进洞位置选择在DK283+700右侧一破旧土房处。但此处埋深较浅,且上部土体均为堆积土,一旦斜井施工,可能会引起周围土体滑坍,威胁周围居民区安全。 2.2 总体方案 斜井施工进洞前有一55米埋深较浅段采用长拉槽开挖,开挖后采用C20砼重力式挡墙支护,挡墙墙高2~6米;同时对暗挖段地表进行注浆加固,然后采用超前管棚进洞。斜井进洞后采用台阶法施工,遵循短开挖、弱爆破、强支护、快封闭、早成环的原则。斜井施工至与正洞交界后,在正洞左侧边墙与横洞交界里程处,以组合焊接一起的3榀I20b钢架作为基础,在此型钢钢架上焊接3榀I20b型钢横梁,为正洞钢架提供落脚平台;同时以圆曲线形式转体进入正洞,同时上坡开挖至正洞拱顶高程,并继续沿相同方向掘进15米(此段设置临时支护,采用拱墙I20b工字钢);形成作业空间后,转向相反方向施工,扩挖临时支护达到正洞标准断面,然后同时向出口施工。 目 录 1.工程概况 .................................................................................................................2 2.总体施工方案...........................................................................................................2 2.1位置选择依据........................................................................................................2 2.2总体方案................................................................................................................2 3.主要参数及工程数量...............................................................................................3 3.1洞身参数................................................................................................................3 3.2支护参数……………………………....................................................................4 3.3主要工程数量………………………....................................................................5 4.施工总体布置...........................................................................................................5 4.1临时工程................................................................................................................5 4.2施工场地布置........................................................................................................6 4.3工期目标................................................................................................................7 4.4人员安排................................................................................................................7 4.5机械设备................................................................................................................8 5施工方法...................................................................................................................8 5.1洞口段施工............................................................................................................8 5.2超前支护................................................................................................................8 5.2.1小导管施工.........................................................................................................9 5.3斜井洞身施工........................................................................................................9 5.3.1斜井排水...........................................................................................................10 5.3.2喷射砼...............................................................................................................10 5.3.3注浆...................................................................................................................10 5.3.4挂钢筋网...........................................................................................................11 5.3.5安I16工字钢.................................................................................................11 5.5斜井转正洞施工..................................................................................................11 5.4仰拱与二衬施工..................................................................................................11 6.监控量测.................................................................................................................12 7.地质超前预报.........................................................................................................12 8.施工安全技术措施.................................................................................................13 9.施工质量技术措施.................................................................................................13 新正阳隧道斜井平面图