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随着我国交通基础设施建设的快速发展,钻孔灌注桩作为一种基础形式以其适应性强、成本适中、施工简便等特点仍将被广泛地应用于公路桥梁及其它工程领域。灌注桩属于隐蔽工程,但由于影响灌注桩施工质量的因素很多,对其施工过程每一环节都必须要严格要求,对各种影响因素都必须有详细的考虑,如地质因素、钻孔工艺、护壁、钢筋笼的上浮、混凝土的配制、灌注等。若稍有不慎或措施不严,就会在灌注中产生质量事故,小到塌孔松散、缩颈,大到断桩报废,给国家财产造成重大损失,直至影响工期并对整个工程质量产生不利影响。据北京全国桩基动测学术交流会上统计资料表明,在被检测的灌注桩中大约有5～10%是有缺陷的,不良地质中灌注桩缺陷率更高达14.7%;从1990～1998年所检测的桩基统计资料中表明,河南省桩基断桩率为5.6%(其它有局部缺陷的未统计)。所以,必须高度重视并严格控制钻孔灌注桩的施工质量,尽量避免发生事故及减少事故造成的损失,以利于工程的顺利进展。
With the rapid development of transportation infrastructure in our country, bored piles as a basic form will be widely used in highway bridges and other engineering fields due to their adaptability, moderate cost and simple construction. Cast-in-situ piles are concealed projects, but due to many factors affecting the construction quality of cast-in-situ piles, every step of the construction process must be strictly required. Various influencing factors must be considered in detail, such as geological factors, drilling technology, Protection wall, steel cage floating, concrete preparation, perfusion and so on. If the slightest carelessness or measures lax, it will produce quality in the perfusion accident, small holes collapsed hole, necking, large broken pile scrapped, causing great losses to the state property until the duration of the project and the quality of the entire project Negative Effects. According to statistics from the Beijing National Pile Foundation Dynamic Measurement Academic Conference, about 5-10% of the bored piles tested are defective, and the defect rate of bored piles in unfavorable geology is as high as 14.7%. From 1990 to 1998 The detected pile foundation statistics show that the pile-cutting rate of pile foundation in Henan Province is 5.6% (other partial defects are not statistically). Therefore, we must attach great importance to and strictly control the construction quality of bored piles, try to avoid accidents and reduce the losses caused by accidents, in order to facilitate the smooth progress of the project.