钢结构作为一种承重结构体系 ,由于具有自重 轻、强度高、塑性韧性好 、抗震性能优越 、工业装配化 程度高、施工工期短、综合经济效益显著、结构体系 灵活、造型美观等诸多优点 ,因而被越来越广泛地应 用于工业厂房、城市轨道 (地铁 ) 车辆段库房 、大型 商场超市等大跨度或超大跨度的各类建筑中 。与其 施工工艺相对应 ,需要为这些建筑建造大型钢筋混 凝土基础或设备基础 ,埋设钢结构 (柱 )与钢筋混凝 土基础联结的结构螺栓。由于钢结构基础大 (上部 多呈四棱台形 ) ,螺栓悬空设置不易固定 ,钢结构安 装质量要求高 ,因此联结螺栓的埋设精度成为钢结 构安装施工的关键技术 。

As a kind of load-bearing structure, steel structure has been widely used in industrial buildings because of its advantages of light weight, high strength, good plasticity, good seismic performance, high degree of industrial assembly, short construction time, remarkable comprehensive economic benefit, flexible structure system and beautiful shape. Urban rail transit (MTR), vehicle depot storehouse, large shopping malls, supermarkets and other large span or super long span buildings. It is necessary to build large reinforced concrete foundation or equipment foundation for the construction of these buildings. The installation quality of the steel structure is higher than that of the steel structure, which is the key technology for the construction of the steel structure, because the steel structure is not easy to fix and the installation quality of the steel structure is high.

 

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1  工艺原理

1 technology principle

 

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利用独立的支架系统和定型模具为预埋螺栓定 位 ,经使用经纬仪或全站仪精确调整、校对后 ,一次 性完成混凝土承台浇注 ,从而达到预埋位置的准确 无误。该工艺流程的特点是 :

By using the independent support system and the set mold for the pre buried bolt positioning, the precise adjustment of the theodolite or the total station instrument is used to finish the concrete cap at one time, thus the accuracy of the pre buried position is achieved. The process is characterized by:

( 1 )由于采用定型模具钢板固定预埋螺栓 , 使 螺栓组内的螺栓相对位置保持准确 。

(1) because the fixed die steel plate is used to fix the embedded bolts, the relative position of bolts in the bolt group is kept accurate.

( 2 ) 利用独立的支架系统和定型模具预埋螺 栓 ,螺栓具有微调性 ,施工操作精度高 ,整体偏差小 。

(2) the use of independent scaffolding system and stereotype mold embedded bolts, bolts with fine tuning, high precision construction operation, the overall deviation is small.

( 3 )充分利用搭设脚手架常用的 Φ 48 mm 钢管 脚手杆和扣件周转材料 ,通用性强 ,费用低 ,可大量节省工程投入。

(3) make full use of the commonly used mm 48 steel tubes, scaffolds and fastener turnover materials, which are commonly used in scaffolding. They are versatile and low in cost and can save a lot of investment in projects.

( 4 )施工工艺简便快捷 ,操作人员容易掌握。

(4) the construction process is simple and quick, and the operator is easy to master.

钢结构预埋螺栓的工艺流程图如图 1 所示 。

The flow chart of embedded bolts for steel structure is shown in Fig. 1.

 

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图 1 工艺流程图

Figure 1 process flow chart

 

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2  施工操作要点

2 main points of construction operation

 

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2. 1  施工准备

2.1 construction preparation

2. 1. 1  地脚螺栓的加工 地脚螺栓应按设计要求加工定制和进场验收, 必须具备相应的材质证明和检验报告 。

2. the processing bolts of the 1.1 bolts should be machined and accepted according to the design requirements.

2. 1. 2  定型模具的设计加工

Design and processing of 2. 1.2 moulds

( 1 )根据预埋地脚螺栓与混凝土基础轴线的相 对位置 ,并考虑模具的组装要求 ,确定模具钢板的平面尺寸 ,刻出模具钢板的纵横轴线十字线 ,然后按模具轴线确定预埋螺栓的相对位置 ,钻孔 。模具的钻 孔位置、孔径要与钢结构柱的螺栓孔位、孔径完全吻合 ,钢板厚度宜 ≮4 mm。

(1) according to the relative position of the pre buried anchor bolt and the axis of the concrete foundation, and considering the assembly requirements of the die, the plane size of the die plate is determined, the cross line of the vertical and horizontal axis of the die plate is carved, and then the relative position of the buried bolt is determined according to the axis of the die. The location and diameter of the drill hole must be exactly the same as the bolt hole position and diameter of the steel structure column, and the thickness of the steel plate should be 4 mm.

( 2 )模具钢板加工好以后可以在现场组装 , 轿 杆采用长度 2. 0 m 的短脚手杆 ,立筋采用 Φ 18 mm 螺纹钢或 Φ 20 mm 钢管 ,立筋高度应高出预埋螺栓5～10 cm ,以方便使用钢尺校对轴线。

(2) when the mould plate is processed well, it can be assembled at the site. The bar adopts the short foot handpole with the length of 2 m, and the vertical bar adopts the 18 mm screw steel or the diameter of the steel pipe, and the height of the erect bar should be higher than the buried bolt 5~10 cm, so that the axis can be proofed by the steel ruler.

( 3 )如果混凝土基础顶部为短柱形 , 可以考虑 在钢板中心挖孔 ,以方便混凝土浇注。

(3) if the top of the concrete foundation is short column, we can consider digging holes in the center of the steel plate to facilitate the pouring of concrete.

2. 1. 3  测量精度的控制

2. 1.3 control precision control

根据工程设计定位坐标及高程 ,加密测设轴线 和高程控制网 ,方便对不同部位的精确测量。

According to the positioning coordinates and elevation of engineering design, the axis and elevation control net are encrypted to facilitate accurate measurement of different parts.

2. 2  施工顺序

2.2 construction sequence

根据钢结构柱的平面布置 ,先从角柱或边柱开 始 ,沿纵轴方向固定预埋螺栓 。如果为多跨度钢结构,应以中间跨纵轴向两侧纵轴流水施工 ,以减小测量和施工误差 ,提高整体安装精度。

According to the plane layout of steel column, starting from the corner column or side pillar, the embedded bolts are fixed along the longitudinal axis. If the multi span steel structure is constructed, it should be constructed in the longitudinal axis of both sides of the longitudinal axis to reduce the error of measurement and construction and improve the overall installation accuracy.

2. 3  独立支架系统的安装

Installation of 2.3 independent support system

钢结构混凝土基础的设计尺寸较大 ,最大宽度 为 3. 8 m ,上部常设计为四棱台形状 ,支模高度远低于地脚螺栓的预埋高度 ,再者钢模或木模都具有一定的柔性 ,达不到预埋螺栓的精度要求 ,因此 ,工程 采用一套独立的支架系统。支架的安装要点如下 :

The design size of the steel structure concrete foundation is larger, the maximum width is 3.8 m, the upper part is often designed as four prism, and the height of the support is much lower than the pre buried height of the anchor bolt. . The installation points of the bracket are as follows:

( 1 )沿纵轴在基础轴线两侧 0. 75 m 左右 (应保证在地梁外侧 ) 拉线 , 沿拉线在基础承台垫层两侧 和基础承台之间设置立杆 ,间距 2. 0～2. 5 m。

(1) along the longitudinal axis of the basic axis, 0.75 m (should be guaranteed at the outside of the ground beam).

( 2 )立杆应打入地基土 30～50 cm (根据土质软 硬程度而定 ) ,高度高出纵向水平杆约 20 mm。纵向 水平杆必须保证水平设置 ,高度应保证预埋螺栓顶

(2) the vertical bar should be inserted into the foundation soil 30~50 cm (according to the degree of soil hardness and hardness), and the height is higher than the vertical horizontal bar about 20 mm. The vertical horizontal bar must be set horizontally, and the height should ensure the embedded bolt top.

符合设计高度并留有上下调整移动的空间。

Meet the height of design and leave room for adjustment.

( 3 )一般的基础承台施工宽度均大于 2. 0 m ,可 将基础两侧立杆和上部水平杆用斜拉杆连接 ,形成 门字形架 ;斜拉杆与水平杆的节点间距 1. 5 m 左右 , 保证水平杆不产生挠度变形。

(3) the construction width of the common base platform is more than 2 m, and the horizontal bar and the upper horizontal bar can be connected with the inclined rod to form a portal frame, and the distance between the joint and the horizontal bar is 1.5 m, so that the horizontal bar does not produce deflection.

( 4 )在斜拉杆与水平杆节点处向两侧架设斜支 撑 (支撑打入地基土深度约 30 cm ) ,然后在支撑附 近安装横向拉杆 ,并在基础上部由水平杆和横向拉 杆组成井字架 ,形成一空间几何不变体 ,确保架体的 刚度和稳定 (见图 2 ) 。

(4) the slanted support is placed on both sides of the inclined rod and the horizontal bar (the depth of supporting the foundation soil is about 30 cm), and then the transverse rod is installed near the support, and the horizontal bar and the transverse rod are formed on the upper part of the foundation to form a space geometric invariant body, which ensures the stiffness and stability of the frame.

 

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图 2 独立支架系统安装示意图

Schematic diagram for installation of 2 independent support system

2. 4  定型模具的就位调整

The position adjustment of 2.4 fixed mold

( 1 )用经纬仪或全站仪在支架系统的井字架上 测设纵横向轴线点 ,拉线形成十字轴线 ,然后把定型 模具轿杆架于井字架水平杆上 ,使模具钢板上的十 字刻线与井字架轴线拉线对正 ,用脚手扣件将轿杆 与水平杆联接 (暂不用扣紧 ,以备调整 ) 。

(1) using the theodolite or the total station to measure the vertical and horizontal axis points on the well character frame of the support system, the drawing line forms the cross axis, and then the stereotype die bar is placed on the horizontal bar of the well character frame, so that the cross line and the well character frame on the die plate are connected to the vertical line, and the sedan bar is connected with the horizontal bar with the foot hand fastener. Be ready to adjust.

( 2 )定型模具就位后 ,拧松轿杆上扣件 ,用小线 坠从井字架的轴线拉线往模具钢板上投点 ,轻轻敲 击轿杆 ,让定型模具前后左右微小移动 ,利用井字架 上的轴线拉线对其进行精确调整

With a small wire rod falling from the axis line of the well word frame to the die plate, it gently knocks the rod to move the mold to the left and right sides of the mold, and adjusts it accurately with the axis line on the well character frame.