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http://dx.doi.org/10.4334/JKCI.2010.22.5.659

Capacity and Length of Compression Lap Splice in Unconfined Concrete of 100MPa and Less Compressive Strength  

Chun, Sung-Chul (Dept. of Architectural Engineering, Mokpo National University)
Lee, Sung-Ho (Architectural Technology Research Team, Daewoo Institute of Construction Technology, Daewoo E&C Co., Ltd.)
Oh, Bo-Hwan (Architectural Technology Research Team, Daewoo Institute of Construction Technology, Daewoo E&C Co., Ltd.)
Publication Information
Journal of the Korea Concrete Institute / v.22, no.5, 2010 , pp. 659-666 More about this Journal
Abstract
Although the compression splice needs not be longer than the tension slice due to existence of end bearing, current design codes impose a longer compression lap splice than a tension lap splice in high strength concrete. Hence, new criteria for the compression lap splice including the effects of concrete strength need to be sought for economical design involving ultra-high strength concrete. An experimental study has been conducted with column specimens in concrete strength of 80 and 100 MPa. Test results show that the splice strength can be evaluated to be proportional to square root of compressive strength of concrete. Bar stress developed by end bearing is not affected by splice length and is expressed with a function of the square root of concrete strength. Mean value of stresses developed by end bearing is 16.5 square root of $f_{ck}$. The stresses developed by bond in compression splices are nearly identical to those in tension splices and, therefore, strength increment of compression splices is attributed to end bearing only. From regression analysis of 58 tests, a design equation is proposed for compression lap splice in 40 to 100 MPa of compressive strength of concrete. By the proposed equation, the anomaly of lap lengths in tension and compression is got rid of. In addition, the equation has a reliability equivalent to those of the specified strengths of materials.
Keywords
compression lap splice; bond; end bearing; splice length; design equation;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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