Prestress loss of RC columns reinforced with prestressed carbon-fiber reinforced polymer fabric using self-locking/wedge-cutting anchorages

doi:10.19936/j.cnki.2096-8000.20220828.001

Abstract

Abstract: To solve the problem of large prestress loss of carbon-fiber reinforced polymer fabric during load-holding process using self-locking anchorage. We developed a wedge-type tensioning and anchoring device for carbon-fiber reinforced polymer fabric based on the "wedge-cutting effect". Under constant temperature and humidity conditions, 12 sets of prestressed carbon-fiber reinforced polymer fabric reinforced RC column specimens were tested. The effects of self-locking/wedge-cut anchorage, column surface roughness, prestress level and one-off/repeated tensioning on prestressing loss were considered, and the friction loss caused by the relative sliding of carbon-fiber reinforced polymer fabric and column surface during tensioning and the prestress losses of carbon-fiber reinforced polymer fabric during load holding were analyzed. The test results show that compared with the self-locking anchorage, the use of wedge-cut anchorage to tension carbon-fiber reinforced polymer fabric can effectively reduce the prestress losses ratio during the carbon-fiber reinforced polymer fabric load-holding process, which in turn can reduce the total prestress losses of carbon-fiber reinforced polymer fabric by up to 41.4%, and the glue coating can reduce the friction loss and prestress losses caused by elastic retraction of carbon-fiber reinforced polymer fabric, and the secondary tensioning can reduce the prestress losses caused by retraction of carbon-fiber reinforced polymer fabric. Based on the test results, the calculation formula of prestress losses is established, which provides a reference for the calculation of prestress losses of carbon-fiber reinforced polymer fabric.

Key words: carbon-fiber reinforced polymer fabric, prestress loss, self-locking anchorage, wedge-cut anchorage, concrete column, composites

CLC Number:

TB332

LU Chun-ling, YUAN Guo-hua, HUANG Dong-fa, WANG Qiang. Prestress loss of RC columns reinforced with prestressed carbon-fiber reinforced polymer fabric using self-locking/wedge-cutting anchorages[J]. COMPOSITES SCIENCE AND ENGINEERING, 2022, 0(8): 5-14.

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