Study On Bond Behavior Of BFRP/GFRP Composite Cement Plate And Concrete Interface Under Erosion Environment

This paper research the interfacial bond property of glass fiber reinforced low alkalinity cement composite board (GFRP composite panel), basalt fiber reinforced ordinary portland cement composite board (BFRP composite board) with cncrete interface under different erosion environment, the test of erosion environment mainly include:freezing and thawing circulation test, alkali resistance tests and SiC (strand in cement) accelerated aging test. The main research contents and results are as follows:(1) Placed GFRP composite specimens, BFRP composite specimen in 5% NaOH solution,7 days,15 days,35 days,70 days of alkali resistance tests, shear test was performed on the specimens. Result from test:with immersion time increase in alkaline solution, the bond stress, interfacial bond slip and interfacial strain of GFRP composite panels, BFRP composite plate and concrete interface show a trend of decrease. After 7 days of alkali resistance tests, the interfacial bond properties are greatly reduced, alkali resistance tests for up to 15 days, the loss rate of interfacial bond property starts to slow down, alkali resistance tests to 70 days, the loss rates of interfacial bond stress were 87% and 86% respectively.(2) 25 times,50 times,100 times of freeze-thaw cycle tests were carried out on GFRP composite specimens and BFRP composite specimens, shear test was performed on the specimens. Result from test:with the increase of the number of freeze-thaw cycles, the bond stress, interfacial bond slip and interfacial strain of GFRP composite panels, BFRP composite plate and concrete interface show a trend of decrease. After 50 times of freezing and thawing, two fiber composite specimen bond performance decreases sharply, GFRP composite adhesive specimen should be the loss rate was 37%, BFRP specimen bond should be the loss rate was 77%, in experienced after 100 cycles of freezing and thawing cycles, the bond force of the rate of loss of slow GFRP composite adhesive specimen should force loss remain unchanged, BFRP composite adhesive specimen should force loss rate was 86%.(3) The GFRP composite specimens, BFRP composite specimens are placed in the hot water of 80℃, accelerated aging test was conducted for 3 days,7 days,11 days, shear test was performed on the specimens. Result from test:with the growth of accelerated aging time, bond performance of GFRP and BFRP composite cement board with concrete interface gradually weakened. The bond strength and interface bond slip showed a downward trend, the loss rate of two kinds of fiber composite specimens the interfacial bond strength is relatively stable, the bond for 11 days after accelerated aging GFRP composite specimens, BFRP composite test piece shall force loss rate was 34% and 36% respectively.(4) After alkali resistant test, freeze-thaw cycle test, accelerated ageing test, GFRP composite specimens of shear bearing force, interfacial bond slip, interface strain were higher than those of BFRP composite test piece, indicating that the GFRP composite specimen interface bonding performance better than BFRP composite specimens.(5) Under the three different kinds of erosion environment, alkaline environment of fiber reinforced cement board and concrete interface bond performance deterioration of the impact is the biggest, accelerated aging on the adhesive properties of the deterioration are the smallest among the three kinds of corrosion environment.