1.1 本试验方法涵盖了使用磁脉冲感应（MPI）（也称为磁成像层析成像或涡流层析成像）评估波特兰水泥混凝土路面传力杆对准的设备、现场程序和解释方法。磁脉冲感应（MPI）装置会感应弱脉冲磁场，从而在干扰磁场的金属物体中感应涡流。当金属（传力杆）进入现场时，通过算法产生和处理电信号，以检测和产生路面接缝中每个传力杆和系杆的深度、对齐和侧移位置的定量值。 1.2 MPI设备包括以下系统:感应磁场并收集电信号的扫描装置、轨道系统等定位系统、从扫描仪收集信号数据、执行现场分析并存储数据的现场数据采集装置、计算传力杆位置的分析软件包，允许数据调整以解释检测到的异常并生成报告。 1.3 MPI现场程序描述了从扫描仪操作和定位系统收集可靠、可重复和准确结果所需的步骤和过程。 对精度至关重要的是，除了测试接头附近的传力杆外，没有任何金属项目。应尽量减少扫描仪和定位系统中的金属。扫描仪操作程序包括收集数据、审查现场数据采集器上的结果以及确定数据收集测试是否成功。 1.4 MPI解释方法描述了如何分析现场程序中收集的数据、为解决干扰而采取的步骤以及在数据分析过程中发现的异常，以提供传力杆位置的准确结果。 此外，还规定了最低报告内容，以产生有意义的测试信息，证明结果。 1.5 单位- 以国际单位制或英寸-磅单位表示的数值应单独视为标准值。每个系统中规定的值可能不是精确的等效值；因此，每个系统应相互独立使用。将两个系统的值合并可能会导致不符合标准。 1.6 本标准并非旨在解决与其使用相关的所有安全问题（如有）。 本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 ====意义和用途====== 5.1 公路、机场和其他设施的混凝土路面接缝因交通和温度变化而承受应力和应变。检查混凝土路面传力杆（见规范 A615/A615米 和 A1078/A1078M )为了防止路面损坏，从而缩短其使用寿命，确保混凝土板之间接缝处的荷载传递有效进行，接缝中的荷载传递非常重要。 使用磁脉冲感应（MPI）检查传力杆为业主和承包商提供了一种无损检测方法，以确定传力杆是否正确安装。MPI检测可在现有接缝上进行，并可支持路面故障的法医调查。 5.2 MPI方法和设备的使用为安装人员提供了一个质量控制过程，以记录传力杆是否正确安装在新路面中。业主使用同一设备进行质量保证活动，并接受承包商安装的设施。 5.3 MPI设备提供可靠的定量结果，不仅可以在同一设备上重复，还可以在其他校准的MPI设备上重复。

1.1 This test method covers the equipment, field procedures, and interpretation methods for the assessment of Portland Cement Concrete Pavement dowel bar alignment using Magnetic Pulse Induction (MPI), also referred to as magnetic imaging tomography or eddy current tomography. Magnetic Pulse Induction (MPI) devices induce a weak pulsed magnetic field that causes the induction of eddy currents in metal objects disturbing the field. When metal (dowel bar) enters into the field an electrical signal is produced and processed through algorithms to detect and produce quantitative values for the depth, alignment and side shift locations of each dowel and tie bar present in the pavement joint. 1.2 MPI equipment includes the following systems scanning device that induces the magnetic field and collects the electrical signal, orientation system such as a rail system, field data collection device that collects the signal data from the scanner, performs field analysis, and stores data, analysis software package that calculates the dowel bar positions, allows data adjustments to account for detected anomalies and produces reports. 1.3 MPI field procedures describe the steps and processes required to collect reliable, repeatable and accurate results from the scanner operation and orientation system. Critical to the accuracy is the absence of any metal items except for the dowel bars in the vicinity of the joints being tested. Metal in the scanner and orientation system should be minimized. The scanner operation procedures cover the collecting of the data, reviewing the results on the field data collector, and determining if the data collection test was successful. 1.4 MPI interpretation methods describe how to analyze data collected in the field procedure, steps taken to address interferences, and anomalies discovered during the data analysis to provide accurate results for the dowel bar positions. Also minimum report content is prescribed for the production of meaningful test information substantiating the results. 1.5 Units— The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== 5.1 Joints in concrete pavements of highways, airfields, and other facilities are exposed to stresses and strains due to traffic and temperature variation. Examining concrete pavement dowel bars (see Specifications A615/A615M and A1078/A1078M ) in joints is important to insure that load transfer at joints between concrete slabs occur efficiently in order to prevent damage to the pavement and thus shortening its service life. Using Magnetic Pulse Induction (MPI) to examine dowel bars provides owners and contractors a non-destructive testing method to determine that the bars are installed correctly. MPI examination can be performed on existing joints and can support forensic investigations into pavement failures. 5.2 The use of MPI methods and equipment provides a Quality Control process for installers to use to document that dowel bars are installed correctly in new pavements. Owners use the same device to perform Quality Assurance activities and accept installed facilities from contractors. 5.3 MPI devices provide reliable quantitative results that are repeatable with not only the same device but also with other calibrated MPI devices.