1.1 这些试验方法包括垂直于短轴和长轴平面加载的切向和死端纤维增强聚合物（FRP）复合横担的弯曲模量和弯曲强度的测定。一种方法包括测试组装的切线横担，包括切线支架和相关硬件。另一种方法包括使用末端支架和相对相位加载硬件对组装的末端横担进行测试。失效模式和相关应力可用于预测特定于导体施加的某些导体负载情况的拉挤横担的相负载能力。 1.2 本标准中描述的试验数据可用于预测死端和切向臂的垂直和水平分量载荷。应分别在图1和图2中描述的两种配置中测试死端横担和正切横担。 这将允许制造商公布末端横担配置的垂直和水平设计能力，以便在公用工程设计工程师和制造商开发末端横担的能力时，可以考虑由悬链线效应引起的双向弯曲应力。 1.3 以国际单位制或英寸磅单位表示的数值应单独视为标准。每个系统中规定的值可能不是完全相等的；因此，每个系统应独立使用。将两个系统的值结合起来可能会导致不符合标准。 1.4 本标准不会涉及影响相位负载能力的所有因素。 1.5 本标准不涉及增加横担结构承载力的核心材料的使用。本标准中提供的计算不应考虑芯材的贡献。 在设计计算中使用核心材料特性来确定横担设计强度的改进是负责项目的指定人员的唯一责任。 1.6 本标准不考虑在标准使用过程中发生的扭转效应。 1.7 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 注1: 目前还没有与该标准等效的ISO。 1.8 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 通过该试验方法测定弯曲模量、梁弯曲强度和全组装强度，对于产品验证、设计和规范目的特别有用。 5.2 弯曲模量、弯曲强度和全组装强度的计算值将随着试样深度、跨度长度、孔配置、加载速率和环境试验温度的变化而变化。建立弯曲模量需要16:1的最小跨度与深度之比，其中剪切变形效应被忽略。 5.3 有效性-- 失效时的应力σ仅适用于局部压缩屈曲引起的横担失效。其他失效控制模式将决定最终阶段负载能力。例如，平面内剪切、紧固件销轴承、定位硬件、中心安装故障和紧固件拔出将决定故障模式和横担承载力。

1.1 These test methods cover the determination of the flexural modulus and bending strength of both the tangent and deadend Fiber Reinforced Polymer (FRP) composite crossarms loaded perpendicular to the plane of minor and major axes. One method covers testing of assembled tangent crossarms including the tangent bracket and relative hardware. The other method covers testing of assembled deadend crossarms with a deadend bracket and relative phase loading hardware. The failure modes and associated stresses can be used for predicting the phase load capacities of pultruded crossarms specific to certain conductor loading scenarios exerted by conductors. 1.2 The test data described in this standard can be used for predicting the vertical and horizontal component loads of deadend and tangent arms. Both deadend and tangent crossarms shall be tested in the two configurations described in Figures 1 and 2, respectively. This will permit the manufacturers to publish both vertical and horizontal design capacities for deadend crossarm configurations so that two way bending stresses, caused by catenary effects, can be considered when developing the capacity of the deadend crossarms by utility design engineers and manufacturers. 1.3 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 nonconformance with the standard. 1.4 This standard will not address all factors that affect the phase loading capacity. 1.5 This standard does not address the use of core materials that are added to increase the structural capacity of the crossarms. Contribution of core materials shall not be considered within the calculations provided in this standard. Use of core material properties in design computations to identify improvement in design strengths of crossarms is the sole responsibility of the designee in-charge of the project. 1.6 Torsional effects occurring during standard in service usage are not considered within this standard. 1.7 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Note 1: There is no known ISO equivalent to this standard. 1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 Determination of the flexural modulus, beam bending strength and full assembly strength, by this test method is especially useful for product validation, design and specification purposes. 5.2 Calculated values for flexural modulus, bending strength and full assembly strength will vary with specimen depth, span length, hole configurations, loading rate, and ambient test temperature. A minimum span to depth ratio of 16:1 is required for establishing the flexural modulus, wherein shear deformation effects are neglected. 5.3 Validity— Stress at failure, σ, is only valid for crossarm failures due to local compression buckling. Other controlling modes of failure will dictate the ultimate phase loading capacities. For example, in-plane shear, fastener pin bearing, position hardware, center mount failures and fastener pull out will dictate the failure mode and the crossarm capacity.