Sliding planes of PTFE are commonly used because of their excellent tribological properties. However, especially in cases of high contact pressures, PTFE suffers from its comparatively poor mechanical properties. This...Sliding planes of PTFE are commonly used because of their excellent tribological properties. However, especially in cases of high contact pressures, PTFE suffers from its comparatively poor mechanical properties. This paper presents a sliding construction developed within an innovative experimental test-setup to enable experimental investigation of large-scale concrete members subjected to punching shear. To fulfill the special demands of the new test-setup, greased, only 0.5 mm thin sheets of PTFE were used to minimize friction between the bearing construction and the test specimen. This highly effective sliding construction leads to a dynamic friction coefficient μ<sub>d,max</sub> between 0.0065 and 0.0035 while the static friction coefficient μ<sub>s</sub> remains below 0.0048. Simultaneously, compressive axial stresses of more than 60 MPa occur. The paper highlights major aspects of the sliding plane’s development and demonstrates its sliding abilities.展开更多
给出 MIL-STD-461F 中拉杆天线试验布置的变化,然后选取有代表性的4个样品进行试验来分析拉杆天线试验布置的变化对测量结果的影响。测量结果表明,在大约5 MHz 以上频段的多个频点,依据 F 版的测量布置得到的测量结果明显小于依据 D 版...给出 MIL-STD-461F 中拉杆天线试验布置的变化,然后选取有代表性的4个样品进行试验来分析拉杆天线试验布置的变化对测量结果的影响。测量结果表明,在大约5 MHz 以上频段的多个频点,依据 F 版的测量布置得到的测量结果明显小于依据 D 版和 E 版的测量布置得到的结果。而对于5MHz 以下的频段,在某些频点上,依据 F 版的测量布置得到的测量结果明显大于依据 D 版和 E 版的测量布置得到的结果。展开更多
文摘Sliding planes of PTFE are commonly used because of their excellent tribological properties. However, especially in cases of high contact pressures, PTFE suffers from its comparatively poor mechanical properties. This paper presents a sliding construction developed within an innovative experimental test-setup to enable experimental investigation of large-scale concrete members subjected to punching shear. To fulfill the special demands of the new test-setup, greased, only 0.5 mm thin sheets of PTFE were used to minimize friction between the bearing construction and the test specimen. This highly effective sliding construction leads to a dynamic friction coefficient μ<sub>d,max</sub> between 0.0065 and 0.0035 while the static friction coefficient μ<sub>s</sub> remains below 0.0048. Simultaneously, compressive axial stresses of more than 60 MPa occur. The paper highlights major aspects of the sliding plane’s development and demonstrates its sliding abilities.
文摘给出 MIL-STD-461F 中拉杆天线试验布置的变化,然后选取有代表性的4个样品进行试验来分析拉杆天线试验布置的变化对测量结果的影响。测量结果表明,在大约5 MHz 以上频段的多个频点,依据 F 版的测量布置得到的测量结果明显小于依据 D 版和 E 版的测量布置得到的结果。而对于5MHz 以下的频段,在某些频点上,依据 F 版的测量布置得到的测量结果明显大于依据 D 版和 E 版的测量布置得到的结果。
