钻芯法检测桩身混凝土强度探讨

Discussion on the Pile Body Strength by Core Drilling Method

钻芯法在检测灌注桩桩长、桩底沉渣厚度,判定或鉴别桩端岩土性状,判定桩身完整性类别等方面非常直观,往往能够取得较好的检测效果。钻芯法用来检测桩身混凝土强度时却受到钻进工艺、芯样试件制作方法及其尺寸等诸多因素的影响。本文结合工程实例的试验数据,介绍了以上因素对钻芯法检测桩身混凝土强度的影响程度,综合国家有关现行规范,推导出了芯样试件抗压强度和混凝土立方体强度的换算公式,并对检测结果和桩身设计混凝土强度等级的关系进行了讨论。

The core drilling method in the testing of pile length and pile bottom slime thickness, distinguishing pile bottom soil （rock） character, determining pile body completeness are extremely directly. However, the factors of boring process, core preparation and sample scale affect the pile body concrete strength in core drilling method test. This article introduced the influence degree of the above factors to test the pile body concrete strength in core drilling method by actual measuring data. Base on the current codes, the reduction formula of the core test piece compressive strength and the concrete cubic strength has been given, and the relationship of the test data and the design pile body concrete strength has been discussed.