MVME2307机械设备卡件
具体指南，包括荷载组合和计算结构耐火性的合理方法，见9.2.1.2.1.3最高使用温度。FRP系统树脂部件的物理和机械性能受温度影响，并在接近或高于其玻璃化转变温度Tg的温度下降解（Bisby等人，2005b）。商用常温固化玻璃钢系统的Tg通常在140至180°F（60至82°C）范围内。特定FRP系统的Tg可从系统制造商处获得，或根据ASTM E1640通过动态力学分析（DMA）测试获得。报告的Tg值应附有测试配置说明；样品制备；固化条件（时间、温度和湿度）；尺寸、加热速率和使用频率。由该方法定义的Tg表示在测试材料从硬脆状态变为软橡胶状态时观察到的储能模量S形变化的外推起始温度。这种转变发生在以Tg为中心的大约54°F（30°C）的温度范围内。这种状态变化将对固化层压板的机械和粘结性能产生不利影响。
对于干燥环境，通常建议FRP系统的预期使用温度不超过Tg–27°F（Tg–15°C）（Xian和Karbhari 2007），其中Tg被视为构成负载路径的系统部件的最低Tg。本建议适用于高温环境，如高温地区或某些工业环境中的高温环境。如果FRP将暴露在潮湿环境中，应使用湿玻璃化转变温度Tgw（Luo和Wong，2002）。可能需要进行测试，以确定FRP在其他环境中的临界使用温度。具体火灾情况在9.2.1.2.1.4中有更详细的描述。最低混凝土基底强度FRP系统需要粘结到完好的混凝土基底上，除非使用美国混凝土协会-版权所有©材料-www.concrete。org 6用于加固混凝土结构的外部粘结FRP系统（ACI 440.2R-17）6.4中的建议。在应用FRP系统之前，应评估和解决现有钢筋的混凝土损坏、劣化和腐蚀问题。
Specific guidelines, including load combinations and reasonable methods for calculating the fire resistance of structures, are given in 9.2.1.2.1.3 Maximum service temperature. The physical and mechanical properties of the resin components of the FRP system are affected by temperature and degrade at a temperature close to or higher than their glass transition temperature Tg (Bisby et al., 2005b). The Tg of commercial room temperature curing FRP systems is typically in the range of 140 to 180 ° F (60 to 82 ° C). Tg for a particular FRP system can be obtained from the system manufacturer or by dynamic mechanical analysis (DMA) testing in accordance with ASTM E1640. The reported Tg value shall be attached with the test configuration description; Sample preparation; Curing conditions (time, temperature and humidity); Size, heating rate and frequency of use. Tg defined by this method represents the extrapolated starting temperature of the S-shaped change in storage modulus observed when the test material changes from a hard brittle state to a soft rubber state. This transition occurs in the temperature range of about 54 ° F (30 ° C) centered on Tg. This state change will adversely affect the mechanical and bonding properties of cured laminates.
For dry environments, it is generally recommended that the expected service temperature of the FRP system does not exceed Tg – 27 ° F (Tg – 15 ° C) (Xian and Karbhari 2007), where Tg is considered the lowest Tg of the system components that make up the load path. This Recommendation is applicable to high temperature environments, such as high temperature areas or high temperature environments in some industrial environments. If the FRP is to be exposed to moisture, the wet glass transition temperature Tgw should be used (Luo and Wong, 2002). Testing may be required to determine the critical service temperature of FRP in other environments. Specific fire conditions are described in more detail in 9.2.1.2.1.4. The minimum concrete base strength FRP system needs to be bonded to a sound concrete base unless the American Concrete Institute - All rights reserved © Materials - www concrete。 Org 6 External bonded FRP systems for strengthening concrete structures (ACI 440.2R-17). Before applying the FRP system, the concrete damage, deterioration and corrosion of existing reinforcement should be evaluated and addressed.
