综合管沟钢筋工程施工技术交底.doc

交底内容：
1.  1. 本工程所用的钢筋材料：d≤8为I级钢筋（HPB235）， d≥10为II级钢筋（HRB335）。
2.  2. 钢筋加工：
3.  （1） 进场钢筋必须有质保书或试验报告单，钢筋进场时分批抽样做物理力学试验。
4.  （2） 钢筋加工的形状、尺寸必须符合设计要求。钢筋的表面确保洁净，无损伤，油渍、漆污和铁锈等在使用前清除干净。不使用带有颗粒状或片状老锈的钢筋。
5.  （3） 钢筋必须平直，无局部曲折。调直钢筋时按下列规定执行：
6.       A.  采用冷拉方法调直钢筋时，I级钢筋的冷拉率不宜大于4%；II级钢筋的冷拉率不宜大于l%。
7.       B.  冷拔低碳钢丝在调直机上调直后，其表面不得有明显擦伤，抗拉强度不得低于设计要求。
8.  （4） 钢筋的弯钩或弯折按下列规定执行：
9.       A.  I级钢筋末端需要作180o弯钩，其圆弧弯曲直径D不小于钢筋直径d的2.5倍，平直部分长度不小于钢筋直径d的3倍。
10.       B.  Ⅱ级钢筋末端需作90o或135o弯折时，Ⅱ级钢筋的弯曲直径D不小于钢筋直径d的4倍，平直部分长度按设计要求确定。
11.       C. 箍筋的末端作成弯钩，弯钩形式按设计要求。
3. 钢筋焊接：
（1） 钢筋焊接使用焊条、焊剂的牌号、性能以及接头中使用的钢板和型钢必须符合设计要求和有关规定，本工程设计要求为： I级钢筋采用T42型焊条，Ⅱ级钢筋采用T50型焊条。
（2） 钢筋焊接前，必须根据施工条件进行试焊，合格后方可施焊。焊工必须有焊工考试合格证，并在规定的范围内进行焊接操作。
（3） 焊接成型时，焊接处应无水锈、油渍等，焊接后在焊接处无缺口、裂纹及较大的金属焊瘤，用小锤敲击时，应发出与钢筋同样的清脆声。钢筋端部的扭曲、弯折必须校直或切除。
（4） 轴心受拉和小偏心受拉杆件中的钢筋接头均采用焊接。普通混凝土
Cards on the table contents:
1.1. The steel used in construction materials: d ≤ 8 for the I grade steel (HPB235), d ≥ 10 for the Grade II steel (HRB335).
2.2. Steel processing:
3. (1) must have a quality assurance approach reinforced the book or test report sheet, reinforced sample batches to do when approaching the physical and mechanical tests.
4. (2) steel processing, shape, size must meet the design requirements. Steel surface to ensure clean, no damage, oil, paint, rust, pollution and cleaned before use. Do not use the old rust with a granular or flake reinforced.
5. (3) bar must be straight, no local complications. Straightening iron bar, according to the following provisions:
6. A. Method of using cold-drawn steel straighten when, I reinforced the cold-drawing class rate of not more than 4%; II grade cold drawn steel bar rate should be less than l%.
7. B. cold drawn low carbon steel wire straight up in the straightening machine, the surface may not have significant abrasion, tensile strength of not less than the design requirements.
8. (4) reinforcement of the hook or bent according to the following provisions:
9. A. I need to make 180o Grade Reinforced end hook, the arc bending diameter D is not less than 2.5 times the bar diameter d, the length of straight part of the bar diameter d is not less than 3 times.
10. B. Ⅱ grade steel needed for the end of 90o or 135o when bending, Ⅱ grade steel curved bar diameter D is not less than 4 times the diameter d, flat part of the design requirements determined by the length.
11. C. stirrup end of Zuocheng hook, hook form according to design requirements.
3. Steel welding:
(1) The use of steel welding electrodes, flux of grades, performance, and joints used in steel and steel must meet the design requirements and relevant regulations, the design called for: I grade T42 steel welding rod used, Ⅱ grade steel welding rod with T50 .
(2) steel welding prior to the test conditions according to the construction welding, welding facilities until they have passed. Welders must have a welder certification, and within the provisions of welding operation.
(3) welding molding, welding rust should be water, oil, etc., in the weld after welding without gaps, cracks and large metal welding tumor, when struck with a hammer, should be issued with the same crisp sound reinforcement. End of the twisted steel, bent or cut straight to school.
(4) axial tension and small eccentric piece of steel rod joints are welded. Ordinary concrete