摘要
通过对广州某花岗岩地区的旋挖成孔灌注桩进行综合试桩,采用静载试验、桩身内力测试、高应变法、低应变法等多种检测手段获得更多的桩-土参数,对强风化花岗岩的承载特性进行研究分析,为设计提供依据并获得了既经济又可靠的设计施工参数。研究表明,试验所在广州地区花岗岩桩侧摩阻力与规范建议值较为接近,但桩端摩阻力差异较大(约为规范建议值的0.3～0.5倍)。鉴于花岗岩土层的土阻力特性,建议在进行花岗岩地区基桩设计前,进行综合试桩,确定所在场地花岗岩土层的各项参数,以确保工程桩的承载力满足设计要求,规避相应风险。
More parameters of pile-soil are obtained through static load test,internal force testing of pile shaft,high-strain dynamic testing, low-strain integrity testing etc. by comprehensive pile testing of rotary excavation bored pile at intensely weathered granite area in Guangzhou, the bearing characteristics of intensely weathered granite are studied and analyzed,which provides the basis for design and obtains both economical and reliable design and construction parameters. The research shows that the skin friction resistance of pile in granite area of Guangzhou is close to the recommended value of the code,but the difference of pile toe frictional resistance is large(about 0.3-0.5 times of the recommended value of the code). In view of the soil resistance characteristics of the granite soil layer,it is suggested to conduct comprehensive test pile before foundation pile design in the granite area,and determine various parameters of the granite soil layer in the site,so as to ensure that the bearing capacity of the project pile meets the design requirements and avoid corresponding risks.
作者
李孟强
Li Mengqiang(Guangdong Tianxin Electric Power Engineering Testing Co.,Ltd. Guangzhou 510663,China)
出处
《广东土木与建筑》
2019年第4期1-5,共5页
Guangdong Architecture Civil Engineering
关键词
强风化花岗岩
承载特性
旋挖灌注桩
intensely weathered granite
bearing capacity
rotary excavation cast-in-situ pile
