岩土工程勘察和试验. 岩土结构试验. 第4部分: 桩试验: 动态荷载试验

[中文适用范围]： 本文件制定了执行动载荷测试的规范，其中单桩承受压缩轴向动载荷。 本文件概述了根据 EN1997​-1:​2004+A1:​2013 中描述的以下方法和程序确定桩抗压性评估所需的测试方法：a) 动态冲击试验 – 通过以下方法确定桩抗压性评估桩头处应变和加速度和/或位移相对于时间的测量结果； c) 波动方程分析——通过对桩、土和驱动设备进行建模，根据打击次数评估桩的抗压强度； b) 打桩公式——根据打桩过程中的打击次数和锤能量评估桩的抗压强度； d) 多次冲击动态测试——通过一系列旨在产生不同水平的桩头位移和速度的冲击来评估桩的抗压强度。 本文件适用于轴向受压的桩。 本文件适用于 EN 1536、EN 12699 和 EN 14199 中提到的所有桩类型。 本文件中考虑的测试仅限于桩的动载荷测试。 注 1 EN 1997-1 中提供了设计中要考虑的桩荷载试验的极限状态系数。 对于符合 EN 1997-1 的设计，动态负载测试的结果将被视为相当于经过适当分析后测得的抗压阻力 Rc,m。 注 2：附件 A、B、D、E 和 F 中给出了动态载荷测试结果分析程序的指南。 本文件提供了以下规范： i) 调查测试，其中牺牲桩被加载至最终极限状态； ii) 控制测试，即桩被加载至超出正常使用极限状态的规定负载。 注3：一般来说，调查测试的重点是桩类型的常识；控制测试侧重于桩的一个特定应用。 1 [外文原描述]： ISO 22477-4:2018 establishes the specifications for the execution of dynamic load tests in which a single pile is subject to an axial dynamic load in compression. ISO 22477-4:2018 outlines the methods of testing required to allow assessment of pile resistance to be determined from the following methods and procedures described in EN1997-1:2004+A1:2013: a) dynamic impact testing ? determination of pile compressive resistance by evaluation of measurements of strain and acceleration and or displacement at the pile head with respect to time; b) pile driving formulae ? evaluation of pile compressive resistance from blow counts and hammer energy during pile driving; c) wave equation analysis ? evaluation of pile compressive resistance from blow counts by modelling of the pile, soil and driving equipment; d) multi-blow dynamic testing ? evaluation of pile compressive resistance from a series of blows designed to generate different levels of pile head displacement and velocity. ISO 22477-4:2018 is applicable to piles loaded axially in compression. ISO 22477-4:2018 is applicable to all pile types mentioned in EN 1536, EN 12699 and EN 14199. The tests considered in this document are limited to dynamic load tests on piles only. NOTE 1 ISO 22477‑4 can be used in conjunction with EN1997-1:2004+A1:2013. Numerical values of partial factors for limit states from pile load tests to be taken into account in design are provided in EN 1997‑1. For design to EN 1997‑1 the results from dynamic load tests will be considered equivalent to the measured compressive resistance Rc,m after being subject to appropriate analysis. NOTE 2 Guidance on analysis procedures for dynamic load testing results is given in Annexes A, B, D, E and F. ISO 22477-4:2018 provides specifications for: i) investigation tests, whereby a sacrificial pile is loaded up to ultimate limit state; ii) control tests, whereby the pile is loaded up to a specified load in excess of the serviceability limit state. NOTE 3 Generally, an investigation test focuses on general knowledge of a pile type; a control test focuses on one specific application of a pile.