Prediction of Shear Strength for Large Anchors Considering the Prying Effect and Size Effect

  • Kim, Kangsik (Department of Architectural Engineering, Hanyang University) ;
  • Lee, Kwangsoo (Department of Architectural Engineering, Yeoju Institute of Technology) ;
  • An, Gyeonghee (Korea Advanced Institute of Science and Technology, Civil & Environmental Engineering)
  • Received : 2016.03.09
  • Accepted : 2016.07.02
  • Published : 2016.12.30


An anchorage system is necessary in most reinforced concrete structures for connecting attachments. It is very important to predict the strength of the anchor to safely maintain the attachments to the structures. However, according to experimental results, the existing design codes are not appropriate for large anchors because they offer prediction equations only for small size anchors with diameters under 50 mm. In this paper, a new prediction model for breakout shear strength is suggested from experimental results considering the characteristics of large anchors, such as the prying effect and size effect. The proposed equations by regression analysis of the derived model equations based on the prying effect and size effect can reasonably be used to predict the breakout shear strength of not only ordinary small size anchors but also large size anchors.


  1. ACI Committee 318. (2015). Building code requirements for structural concrete (ACI 318), Farmington Hills, MI.
  2. ACI Committee 349. (2015). Code requirements for nuclear safety related concrete structures (ACI 349-13), Farmington Hills, MI.
  3. Arkansas Nuclear One Steam Electric Station. (1992). Arkansas nuclear one maxibolt anchor bolt test program, entergy operations. MCS Design
  4. ASTM A 540. (2005). Standard specification for alloy-steel bolting materials for special applications: Class B.
  5. ASTM E 488-98. (1998). Standard test methods for strength of anchors in concrete and masonry elements.
  6. Bailey, J. W., & Burdett, E. G. (1977). Edge effects on anchorage to concrete. Civil Engineering Research Series, 31, 120.
  7. Bazant, Z. P., & Planas, J. (1997). Fracture and size effect in concrete and other quasibrittle materials. Boca Raton, LA: CRC Press.
  8. Federation Internationale du Beton (fib). (2013). fib model code for concrete structures 2010. Berlin, Germany: Ernst & Sohn.
  9. Fuchs, W., Eligehausen, R., & Breen, J. (1995). Concrete capacity design (CCD) approach for fastenings to concrete. ACI Structural Journal, 92(6), 794-802.
  10. Hallowell, J. (1996). Tensile and shear behavior of anchors in uncracked and cracked concrete under static and dynamic loading. M.S. Thesis, The University of Texas at Austin.
  11. Klingner, R. E., & Mendonca, J. A. (1982). Shear capacity of short anchor bolts and welded studs: A literature review. Journal of the American Concrete Institute, 79(5), 339-349.
  12. Klingner, R., Mendonca, J., & Malik, J. (1982). Effect of reinforcing details on the shear resistance of short anchor bolts under reversed cyclic loading. ACI Journal, 79(1), 3-12.
  13. Klingner, R. E., Muratli, H., & Shirvani, M. (1999). A technical basis for revision to anchorage criteria, NUREG/CR-5563.
  14. Korea Concrete Institute (KCI). (2012). Concrete design code; Design guidline for anchoring to concrete.
  15. KS F 2405. (2010). Standard test method for compressive strength of concrete.
  16. Lee, N. H., Park, K. R., & Suh, Y. P. (2010). Shear behavior of headed anchors with large diameters and deep embedments. ACI Structural Journal, 107(S14), 146-156.
  17. McMackin, P., Slutter, R., & Fisher, J. (1973). Headed steel anchors under combined loading. AISC Engineering Journal, 10(2), 43-52.
  18. Ollgaard, J., Slutter, R., & Fisher, J. (1971). Shear strength of stud connectors in lightweight and normal weight concrete. AISC Engineering Journal, 8(2), 55-64.
  19. Swirsky, R., Dusel, J., Crozier, W., Stoker, J., & Nordlin, E. (1977). Lateral resistance of anchor bolts installed in concrete, report no. FHWA-CA-ST-4167-77-12. California Department of Transportation, Sacramento, CA.