Requirements for steel bar binding

　　通常，綁扎鋼筋時須依照以下要求來進行：

　　Usually, the binding of reinforcing bars should be carried out according to the following requirements:

　　（1）鋼筋網片綁扎。鋼筋的交叉點應選用20～22號鐵絲綁扎。對于板和墻的鋼筋網，除接近外圍兩行鋼筋的相交點應悉數扎牢外，中間部分交叉點可距離交替扎牢，但有必要保證受力鋼筋不發作方位偏移；在接近外圍兩行鋼筋的相交點好按十字花扣綁扎；綁扣的方向應根據具體情況交織地改變，以免網片朝一個方向歪扭。對于面積較大的網片，可適當地用鋼筋作斜向拉結加固。雙向受力的鋼筋須將一切相交點悉數扎牢。

　　(1) Reinforcement mesh binding. The crossing point of reinforcing bar should be tied with wire No. 20-22. For the reinforcing steel mesh of slab and wall, besides the intersection point of two rows of steel bars close to the periphery, the intersection point of the middle part can be secured alternately, but it is necessary to ensure that the stressed reinforcing steel bars do not suffer from azimuth deviation; the intersection point of two rows of steel bars close to the periphery should be bound by cross-stitching; the direction of the binding should be changed interlacingly according to the specific situation, so as to avoid the distorted mesh in one direction. For large meshes, reinforcement with steel bars can be properly used as oblique tension reinforcement. All intersecting points shall be firmly secured by two-way loaded steel bars.

　　（2）梁和柱的箍筋。對梁和柱的箍筋應與受力鋼筋堅持筆直；箍筋彎鉤疊合處應沿受力鋼筋方向錯開放置。其中梁的箍筋彎鉤應放在受壓區，在個別情況下，例如接連梁支座處，受壓區在截面下部，要是箍筋彎鉤位于下面，有可能被鋼筋壓“開”，這時，只好將箍筋彎鉤放在受拉區（截面上部，即受力鋼筋那一面），但應特別綁牢，必要時用電弧焊點焊幾處。

　　(2) stirrups of beams and columns. The stirrups of beams and columns should be straight with the stressed steel bars, and the bending hooks of the stirrups should be staggered along the direction of the stressed steel bars. The hoop hook of the beam should be placed in the compression zone. In some cases, such as the support of the connecting beam, the compression zone is at the lower part of the section. If the hoop hook is located below, it may be "opened" by the steel bar. At this time, the hoop hook has to be placed in the tension zone (the upper part of the section, that is, the side of the stressed steel bar), but it should be tied up specially and welded with arc welding points when necessary.

　　（3）柱縱筋彎鉤朝向。綁扎矩形柱的鋼筋時，角部鋼筋的彎鉤平面應與模板面成45（多邊形柱角部鋼筋的彎鉤平面應位于模板內角的平分線上；圓形柱鋼筋的彎鉤平面應與模板切平面筆直，即彎鉤應朝向圓心）；矩形柱和多邊形柱的中間鋼筋(即不在角部的鋼筋)的彎鉤平面應與模板面筆直；當選用刺進式振搗器澆筑截面很小的柱時，彎鉤平面與模板面的夾角不得小于15°。

　　(3) The bending hook of column longitudinal reinforcement is oriented. When binding the steel bar of rectangular column, the hook plane of the corner steel bar should be 45 (the hook plane of the polygonal column corner steel bar should be located on the bisector of the inner corner of the template; the hook plane of the circular column steel bar should be straight with the tangent plane of the template, that is, the hook should be oriented towards the center of the template); the hook plane of the middle steel bar of the rectangular column and the polygonal column (that is, the steel bar not at the corner) should be straight with the template plane. The angle between the bending hook plane and the plate surface shall not be less than 15 degrees when a column with a small cross section is poured by a piercing vibrator.

　　（4）構件交叉點鋼筋處理。在構件交叉點，例如柱與梁、梁與梁以及結構和桁架節點處桿件交匯點，鋼筋縱橫交織，大部分在同一方位上發作碰撞，無法裝置。這種情況有必要在施工前的審圖進程中就予以處理。處理辦法一般是使一個方向的鋼筋設置在規定的方位（按規定取保護層厚度），而另一個方向的鋼筋則去避開它（常以調整保護層厚度來完成）。

　　(4) Reinforcement treatment at the intersection of members. At the intersection points of members, such as the intersection points of columns and beams, beams and beams, and structural and truss joints, steel bars are interwoven vertically and horizontally. Most of them collide in the same direction and cannot be installed. This situation needs to be dealt with in the process of drawing examination before construction. In general, the treatment method is to set the reinforcement in one direction in the prescribed direction (the thickness of the protective layer is taken according to the prescribed), while the reinforcement in the other direction avoids it (usually by adjusting the thickness of the protective layer).

　　（5）鋼筋方位的固定。裝置鋼筋方位準確，施工時應使鋼筋不出現位移，必要時預先設置相應的支架、墊塊或墊筋加以固定。

　　(5) fixing the orientation of reinforcement. The installation has accurate orientation of reinforcing bars. The reinforcing bars should not be displaced during construction. If necessary, corresponding brackets, cushion blocks or cushion bars should be set in advance to fix them.

　　（6）鋼筋保護層。保護層小厚度（從受力鋼筋外皮算起）應符合規定，且不應小于受力鋼筋的直徑。傳統的做法是在現場使用水泥砂漿制作出必定厚度的墊塊。

　　(6) Reinforcement protective layer. The minimum thickness of the protective layer (calculated from the outer skin of the stressed steel bars) shall be in accordance with the regulations and shall not be less than the diameter of the stressed steel bars. The traditional method is to use cement mortar to make pads of certain thickness on site.