管涵沟槽开挖、回填技术交底.doc

交底内容：
本工程管涵位于K0+288里程处，为钢筋混凝土管。
一、沟槽土方开挖：
1.  沟槽开挖前的准备工作：
(1).  根据设计图纸的设计要求进行测量放线，定出中心桩、槽边线。
(2).  先查明段地下管线及其它地下构筑物情况，会同有关部门作出妥善处理，确保施工安全
(3).  沟槽开挖前应做好沟槽外四周的排水工作，保证场外地表水不流入沟槽。
(4).  按工程监测要求，开挖前先布置各种类型的观测点，并测定初始资料。
(5).  准备好所有的机械设备及场内外运输道路，以利土方开挖工作连续快速完成。
2.  沟槽开挖方法：
(1).  土方开挖采用自然放坡开挖，放坡系数为1：0.5，喷射10cm厚素混凝土硬化坡面。
(2).  开挖方式以机械开挖为主，人工开挖进行配合。土方采用分段分层开挖的方式进行，开挖深度3.0m以内的采用挖掘机一次开挖至距沟槽底20.0cm，开挖深度超过3.0m的，采用挖掘机分两次开挖至距沟槽底20.0cm，挖出的土方用自卸运土车运至指定余泥堆场。
沟槽基底标高以上20cm的土层，采用人工开挖、清理、平整，以免扰动基底
Cards on the table contents:
The project culvert at K0 +288 Mileage for reinforced concrete pipe.
1, trench soil excavation:
1. Trench excavation preparatory work before:
(1). According to the design drawings of the design requirements for measuring and setting out, set the Pile, groove edges.
(2). First identify the section of underground pipelines and other underground structures in the situation, together with relevant departments to provide appropriate treatment to ensure the construction safety
(3). Trench excavation should be prepared prior to the drainage trench around the outside work to ensure that surface water does not flow outside the trench.
(4). According to project monitoring requirements, layout of various types of excavation prior to the observation point, and the determination of the initial data.
(5). Ready for all the mechanical equipment and OTC road transport to facilitate the rapid completion of a continuous earth excavation work.
2. Trench excavation methods:
(1). Earthwork excavation by natural sloping excavation, up slope coefficient of 1:0.5, jet 10cm thick plain concrete hardening slope.
(2). Excavation by mechanical excavation of the main excavated to meet. Sub-layer earth by way of excavation, the excavation depth of less than 3.0m with an excavator from the trench excavation to the end of 20.0cm, excavation deeper than 3.0m, the use of excavators digging in two to from the trench bottom 20.0cm, earthwork excavated earth with dump trucks to the named Yuni yard.
Elevation above basal trench 20cm of soil, using artificial excavation, clearing, leveling, to avoid disturbance basement