论文 混凝土裂缝

论文 混凝土裂缝 现浇混凝土施工裂缝成因及防范的分析 (浅谈现浇混凝土的裂缝) 现浇混凝土的裂缝是众多新老施工人员都遇到过且处理较为麻烦的问题，如若采取的措施没有针对性、方法不恰当，所产生的后果不仅裂缝处理不了，而且引起的负面影响相当大。混凝土毕竟是一种人为的和成品，从材料的选择、施工工艺的完善性、施工管理的严密性、混凝土体积的大小、地基不均匀沉降等等各种因素综合影响，致使钢筋混凝土形成大小不一的裂缝。如何对现浇混凝土裂缝进行必要的、可行的预防措施及正确、准确的处理方法，以下是本人通过参阅各种资料结合多年的实际施工经验对现浇混凝土裂缝进行的总结: 一、现浇混凝土裂缝的认识 现浇混凝土产生裂缝是不可不免的，但裂缝产生的危害程度可以通过有效的补救措施来减小甚至消灭。通过查阅各种资料得知国内一般对于混凝土结构裂缝大于0.2?作为必须处理的有害裂缝，而国外对裂缝的规定不完全一致，但大致相同，最严格的允许裂缝宽度为0.1?，但由于各国技术要求不尽相同，混凝土所处环境相对理想，钢筋混凝土裂缝可放宽至0.4?。在众多混凝土形式中预应力混凝土裂缝的控制尤为严格，预应力混凝土通过裂缝对钢筋进行腐蚀，有可能产生脆性断裂，预兆性小裂缝扩展速度快、破坏性大，裂缝深度h?0.1H表面裂缝;0.1H,h,0.5H浅层裂缝;0.5H?h,1.0H纵身裂缝;h=H贯穿裂缝。应当尽量避免贯穿性及纵深裂缝，如果出现此裂缝应当采取化学灌浆处理来保证强度，也就是说贯穿裂缝抗拉强度必and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 须超过混凝土抗拉强度。一般按混凝土裂缝形成时间分为早期裂缝:出现在一个月之内;中期裂缝约在6各月之内;以后的裂缝属于后期裂缝，最长时间的裂缝可发生在3年以后。 二、现浇混凝土裂缝的成因 现浇混凝土裂缝形成后首先要对裂缝的宽度、位置、形成时间、结构环境等进行详细的分析，确定裂缝是否已经稳定，然后再编制针对性的处理 方案 气瓶 现场处置方案 .pdf气瓶 现场处置方案 .doc见习基地管理方案.doc关于群访事件的化解方案建筑工地扬尘治理专项方案下载 并严格按方案执行。 1、因水泥水化热升为快混凝土内外温差产生的裂缝 这种裂缝一般多发生于大体积混凝土施工中，混凝土浇筑2-3天后裂缝最为明显，主要原因是施工中未严格控制水泥含量及水泥品种，没有考虑外界气温高等环境温度条件，对混凝土早期强度升高快，水化热释放量高，未采取有效的降温措施，导致混凝土内部热胀量过大而表面温度相对低，热胀量相对较低，而产生裂缝，如果控制不力形成贯缝则会影响混凝土整体强度，甚至混凝土无法满足设计要求，需要补强或报废处理。 2、现浇混凝土自身干缩及沘水而产生的裂缝 这种裂缝主要产生于砼水灰比过大在硬化过程中表面温度变化大的情况。 (1)混凝土沘水的影响:施工中混凝土振捣不密实。致使混凝土内部水分的逸出会受到大骨料的阻滞 在骨料四周形成暂时无法蒸发的水囊，随时间的延长，水份慢慢蒸发、干燥使其相应部位形成深部微裂缝，微裂缝存在于水泥浆及骨料的结合面上。即通常所说的“结合and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 缝”结合缝也可以由水泥浆的收缩产生。在混凝土硬化过程中，温度变化大。在混凝土内部产生拉应力，也可产生温度胀缩裂缝。 (2)混凝土中水泥硬化干缩的影响:水泥浆在硬化过程中，水份的蒸发使混凝土产生塑性收缩，由水泥及砂的混合物在强度上升的过程中不断收缩，而粗骨料会限制此种收缩，导致在结合面上产生微裂缝，同时混凝土中水份的不断蒸发，空隙水中毛细管表面张力产生变化，使毛细管出现裂缝，混凝土中掺假外加剂的碱骨料反应产生内部应力膨胀裂缝，混凝土浇筑过程中振捣不足或振捣过密，时间过长使混凝土产生离析和沘水现象，在混凝土表面形成水泥含量较多的水泥浆层，表面水份损失过快，易形成收缩裂缝;混凝土配合比不良，胶—骨料过大和砂率过大，混凝土本身缺少抵抗温度，干缩变形的骨架作用也易造成混凝土裂缝。 (3)混凝土中水份逸出的影响:混凝土的干缩主要是由混凝土中的变化产生的，当混凝土长期在水中硬化时会产生微小的膨胀;当混凝土在空气中硬化时混凝土的水份会逐渐逸出蒸发，使混凝土中的胶凝体逐渐干燥而产生收缩，从而引起混凝土中的干缩裂缝。混凝土用水量的大小十决定干缩大小的最主要的因素，混凝土的水灰比越大，干缩率越大，即在水灰比相同的条件下，水泥浆含量越大混凝土的干缩越严重。 (4)混凝土施工工艺及环境的影响:混凝土的养护不当也是造成现浇混凝土裂缝的主要原因，过早的养护会影响混凝土的胶结能力，过迟的养护混凝土表面游离水蒸发过快，水泥缺少必要的水化水而产生3 and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 急剧的体积收缩，英气裂缝;施工中混凝土未达到规定强度过早拆模，模板支撑方法不当、模板刚度不够、拆模时强行敲打。混凝土浇筑时上层钢筋产生沉降，绝大部分出现在浇筑混凝土之后1,2小时左右，裂缝沿着钢筋方向出现，若当时用抹子抹平，一般可以弥补;骨料未清洗洁净，含土量大而多，会产生不规则的网状裂缝;施工缝处得浮浆处理不当而出现裂缝;木模板未浇透水，模板吸水膨胀将梁、柱、板角拉裂;预制构件翻转模板施工时，受震动过大或因施工面的砂子没有铺平，在构件成型过程中或受剧烈震动产生纵向或横向裂缝;有的工程在混凝土未达到终凝时间就上荷载，施工中不注意钢筋的保护，钢筋的位移，后浇带未按设计规范要求施工也都是造成混凝土产生裂缝的因素;混凝土本身是一种具有热胀冷缩性质的材料，在混凝土初凝阶段会产生水化热，使混凝土的温度升高，当温度降低时便会收缩，种种收缩达到一定程度或受到一定约束，如混凝土内部和表面温差较大，特便是气温骤降，混凝土内产生膨胀，外部收缩造成其内外变形的不一致，混凝土就会开裂，因此有些工程施工时为了避免出现此类情况将大体积混凝土的浇筑时间该在夜间进行，特别是水利工程中的混凝土在浇筑时还采用循环水、冷冻混凝土骨料搅拌、分块浇筑等方法来避免出现过大的混凝土内外温度差。 三、现浇混凝土裂缝防范措施 从以上现浇混凝土裂缝的成因来看，混凝土形成裂缝是多方面的，复杂的因素，因此对于不同的地域、不同的工程性质、不同的工程环境等混凝土结构，其裂缝的防治应采取多种角度、多方面的措施，and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 使之避免产生裂缝或使裂缝发生几率及危害降到最低点。 1、在工程前期设计阶段就应适当考虑裂缝出现的可能性，选用适当的原材料配置混凝土使尽可能的减少收缩。对于大体积混凝土应采用水化热低的矿渣水泥、粉煤灰水泥。掺加适宜的外加剂，如添加减水防裂剂，改善水泥浆的稠度，提高混凝土的抗拉强度。精细骨料的选择，采用适宜的砂率。注意混凝土在硬化过程中因温度湿度的变化而产生收缩，尽量减少混凝土收缩时遇到的约束。例如在适应结构要求的情况下，以适当间距预留胀缩缝或施工缝。同时注意相邻构件因混凝土收缩互相引起约束作用。正确地选择结构和截面形成，在尺寸变化较大的洞口、转角等部位，要防止因收缩引起的应力集中。 2、严格控制水灰比，混凝土的水灰比越大，收缩率越大，开裂的可能性也越大。因为水灰比越大，水泥浆越稀，硬化成水泥石后所含凝胶体越多，晶体越少，而干燥收缩主要是凝胶体的干燥收缩所引起的。因而拌制混凝土时应尽量减小水灰比，同时在混凝土硬化过程中加强养护工作，混凝土搅拌充分，材料搅拌前准确称量来防止开裂现象。 3、注意温度的变化。在夏季施工时，应尽可能降低混凝土的入仓温度。如施工时气温过高，应加遮盖防止太阳光暴晒混凝土材料，或采取淋水降温的办法。大体积混凝土采取分块浇筑，并严格按规范要求设置伸缩缝。冬季采用覆盖保护施工，应当在混凝土达到足够强度时在拆模板和取消覆盖物 4、混凝土的运输应当注意方式，严格掌握混凝土从搅拌机卸出后到浇筑完毕的延续时间，不得超出规范的要求和试配的初凝时间，对商5 and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 品混凝土应就进选择搅拌站，并向搅拌战提出具体的技术要求，包括施工部位、强度等级、塌落度及允许偏差，有无早强及缓凝要去、初凝时间、浇筑速度等。 5、混凝土的养护工作一定要与实际混凝土凝结时间同步。养护不良不但会造成裂缝，而且会使混凝土品质下降。因此应加强混凝土保温养护工作，提别是雨天施工，混凝土表面要防雨水冲淋。适当的延长养护时间，时混凝土强度增加，有助于减少裂缝的产生。混凝土一般应在浇筑完成后12小时内对混凝土加以覆盖保湿养护。根据采用水泥品种不同，确定养护时间，洒水养护应以保持混凝土处于湿润状态为宜。薄膜布养护应在混凝土振捣后二次抹压立即用塑料薄膜严密覆盖，保证混凝土在不失水的情况下得到充足的养护，同时辅以洒水养护。对于大面积楼板也可用蓄水养护。冬季混凝土应采取可行的养护方法，如蓄热法、覆盖养护、暖棚法养护、电热法养护等。 6、控制水泥用量，尽可能降低水泥用量，掺用减水剂，改善混凝土和易性。一般情况下，若水灰比不便，则水泥含量越多混凝土的干缩率越大，因为混凝土的干缩主要产生于水泥浆的干缩，水泥越少，混凝土中的骨料对于干缩的制约作用越显著。若同时减少用水量，对于改善干缩，提高混凝土的裂缝控制会更加有效。对于不同的混凝土构件，应有针对性的采用相应的浇筑工艺，浇筑大体积混凝土首先应制定详细的浇筑方案，采取切实可行的措施:合理分缝分块浇筑，安排合理的浇筑顺序;夏天浇筑混凝土分层施工，减小浇筑厚度，利用浇筑层面散热;在混凝土中埋设降温水管，通入冷水降温;合理安排浇and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 筑顺序，避免过大的高差和侧面长期暴露;注意控制钢筋位置，防止钢筋位移造成混凝土保护层过大而开裂;特别是浇筑薄型构件时，控制措施尤为重要:严禁在浇筑时在混凝土中加水。尽量避免高温天气施工。浇筑时及时移动含布料管，以防止出料口处混凝土过于集中。使用合适的振捣设备，在浇筑前，应将基层和模板充分湿润，振捣时避免过度或不足。混凝土振捣完后，先用木刮刮平，在初凝时，用木抹子做第一次抹压，要求加力较大，使面层充分达到密实，在混凝土终凝前进行二次抹压，抹压力应比第一次抹压力较大，使混凝土面层再次充分达到密实。 7、地基木模变形裂缝，支撑模板地基也必须夯实，以防止模板和支撑移动。浇筑混凝土前，易将木模浇水湿透。 四、现浇混凝土裂缝的处理 钢筋混凝土结构的裂缝问题和应注意的防裂缝措施都是施工管理中老生常谈的内容，但是在实际工程建设中我们仍不时碰到裂缝问题。发现裂缝后施工需要对它修补和如何修补，主要应根据结构的使用要求，充分分析裂缝产生的原因，对照设计和施工规范中的规定，根据不同情况采取不同的措施。一般我们有以下几种处理方法: 1、表面处理法:分为表面涂抹和表面贴补法。表面涂抹适用范围是浆材难以灌入的细而浅的裂缝，深度未到达钢筋表面的发丝裂缝，不漏水的缝，不伸缩的裂缝以及不再活动的裂缝。表面贴补法适用于大面积漏水的防渗堵漏。若裂缝对于承载力无影响主要为了防渗防漏，可在修补前先对基底进行充分处理，将裂缝附近的混凝土凿毛或凿成7 and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 深15,20?，宽50,100?的槽，槽面清除干净并用水湿润，水泥纯浆一次，然后用膨胀水泥砂浆或1:2普通水泥砂浆分层压实抹光。用塑料薄膜或草袋等覆盖，洒水养护。还有一种方法是裂缝表面涂抹环氧胶泥或用环氧粘贴玻璃布，效果也很好。 2、填充法:用修补材料直接填充裂缝，一般用来修补较宽的裂缝(大于0.3?)，作业简单，费用低。宽度小于0.3?，深度较浅的裂缝、或是裂缝中有充填物，用灌浆法很难达到效果的裂缝、以及小规模裂缝的简易处理可采取开V型或U型槽，槽面洗刷干净后填充水泥砂浆、环氧树脂、聚氯乙烯胶泥或沥青油膏等。 3、灌浆法:此法应用范围广，从细微裂缝到大裂缝均可适用，处理效果好。用电钻钻孔穿过裂缝缝面，用压浆泵将胶结材料压入缝内。胶结材料可用水泥浆、甲凝、丙凝或环氧树脂浆液等。 4、结构补强法:因超荷载产生的裂缝、裂缝长时间不处理导致的混凝土耐久性降低、火灾造成的裂缝等影响结构强度可采取结构补强法。包括断面补强法、锚固补强法、预应力法等。混凝土裂缝处理效果的检查包括修补材料试验:钻芯取样试验、压水试验、压气试验等。 总之，为了防止钢筋混凝土结构产生裂缝我们在施工中尽可能采取各种有针对性的措施，避免有害裂缝的出现，确保工程质量要求。这也是我们每一个工程人员的职业操守。 and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm)