An Experimental Study on Shrinkage Strains of Normal-and High-Strength Concrete-Filled Frp Tubes

International Conference on Materials Sciences and Nanomaterials

材料科学;物理学

Vincent, Thomas^1 ; Ozbakkaloglu, Togay^2

School of Computer Science, Engineering and Mathematics, Flinders University, Adelaide

SA

5042, Australia^1

School of Civil, Environmental and Mining Engineering, University of Adelaide, Adelaide

SA

5005, Australia^2

关键词: Circular cross-sections;    Concrete compressive strength;    Concrete shrinkage;    Construction technique;    Fiber reinforced polymers;    Normal- and high-strength concretes;    Shrinkage measurements;    Shrinkage strains;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/230/1/012007/pdf
DOI  :  10.1088/1757-899X/230/1/012007

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

It is now well established that concrete-filled fiber reinforced polymer (FRP) tubes (CFFTs) are an attractive construction technique for new columns, however studies examining concrete shrinkage in CFFTs remain limited. Concrete shrinkage may pose a concern for CFFTs, as in these members the curing of concrete takes place inside the FRP tube. This paper reports the findings from an experimental study on concrete shrinkage strain measurements for CFFTs manufactured with normal- and high-strength concrete (NSC and HSC). A total of 6 aramid FRP (AFRP)-confined concrete specimens with circular cross-sections were manufactured, with 3 specimens each manufactured using NSC and HSC. The specimens were instrumented with surface and embedded strain gauges to monitor shrinkage development of exposed concrete and concrete sealed inside the CFFTs, respectively. All specimens were cylinders with a 152 mm diameter and 305 mm height, and their unconfined concrete strengths were 44.8 or 83.2 MPa. Analysis of the shrinkage measurements from concrete sealed inside the CFFTs revealed that embedment depth and concrete compressive strength only had minor influences on recorded shrinkage strains. However, an analysis of shrinkage measurements from the exposed concrete surface revealed that higher amounts of shrinkage can occur in HSC. Finally, it was observed that shrinkage strains are significantly higher for concrete exposed at the surface compared to concrete sealed inside the CFFTs.