Development of Design Recommendations for Noncontact Hooked Bar Lap Splices for Large Reinforcing Bars

Details

• Creators:
  Coleman, Zachary W ; Brown, Mason ; Roberts-Wollmann, Carin L. ; Jacques, Eric ; Kassner, Bernard L.
• Corporate Creators:
  Virginia Polytechnic Institute and State University. Charles E. Via Department of Civil and Environmental Engineering ; Virginia Transportation Research Council (VTRC)
• Corporate Contributors:
  Virginia. Department of Transportation ; United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  Accelerated Bridge Construction Anchorages Bond And Development Lap Joints Noncontact Lap Splice Precast Concrete Recommendations Reinforcing Bars Splicing
• Publication/ Report Number:
  FHWA/VTRC 26-R31
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Virginia
• Edition:
  Final Contract
• Corporate Publisher:
  Virginia Transportation Research Council (VTRC)
• Abstract:
  On wide bridges, precast concrete pier caps are often constructed in multiple segments and connected on site because of transportation or construction limitations. When these segments are connected through closure joints, contractors use lap splices of straight reinforcing bars. However, the splice lengths of large (e.g., No. 11) straight bars must be very long to develop the yield strength of the bars. The cost of long splices may offset the benefit of using precast concrete. To reduce splice lengths, bridge designers use hooked bars in noncontact lap splices, presuming that hooked bars allow for shorter splice lengths. The use of noncontact splices avoids conflicts during fit-up in the field. However, neither substantial design guidance nor studies of the behavior of hooked bar lap splices in large concrete elements exists to justify this design philosophy. To develop design guidance for noncontact hooked bar lap splices, 73 large-scale beam-splice specimens were tested to simulate the closure connection between precast pieces. The bond and anchorage parameters of the noncontact hooked bar lap splices varied, including parameters such as the splice spacing, concrete compressive strength, cover depth, casting position, number of spliced reinforcement layers, hook shape, splice length, number of bundled bars, number of lap splices, amount of transverse reinforcement, and dosage of steel fibers. In addition, nonlinear finite element analyses were conducted to investigate the force transfer mechanism in noncontact hooked lap bar splices and predict splice strength over a wider range of splice configurations than tested in the laboratory.
• Format:
  PDF
• Funding:
  119918
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:7ab0d9ebe5954ca8a5c42fab4b537198ce9edef2ae439b46184424db0dbf3db4c8698c8883737cd4c94bdf5b95f60e0e2b698fc21f5a2d22d7810665d6f219a5
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/89146/dot_89146_DS1.pdf
• File Type:
  [PDF - 4.59 MB ]