Analytical and Field Experimental Studies on Hollow Core Slab Beam Bridges Strengthened by a U-section Steel and Concrete Composite Anchorage System

This paper studies the mechanism of the “Single Slab Load Bearing” phenomenon of Hollow Core Slab Beam (HCSB) Bridges that count for about 25% of the total bridges in China. The typical structure of HCSB bridges is to place prefabricated slab beams side by side, and then connect adjacent slabs laterally with hinge joints. Finite element models were developed for HCSB bridges with 13m, 16m, and 20m simple spans, the most commonly used lengths of this type of bridges. The traditional design of HCSB bridges with small sized hinge joints covered by a 10 cm deck was found insufficient for the standard design trailer-100 load; the maximum normal stress in hinge joints exceeded the specification limits, which caused the damage of the joints. With the failure of hinge joints, the maximum normal stress in the deck reached 5.3MPa, which exceeded the design strength and caused wide longitudinal cracking in the deck; as a result, the “Single Slab Load Bearing” phenomenon occurs. To solve this problem, the authors proposed a new strengthening technique by installing a U-section Steel and Concrete Composite Anchorage System attached to the bottom of hinge joints. The system can be installed without interruption to traffic. A 3-dimensional finite element analysis demonstrated a significantly improved bridge performance after strengthening; the maximum stress in hinge joints decreased by about 90%, and the maximum normal stress in slabs decreased by 44.7%. Furthermore, tensile stresses in the deck were completely removed. A field load test on a HCSB bridge before and after rehabilitation verified the finite element results. Stresses and deflections at the mid-span of slabs were measured under six load cases; both were found decreased by around 30% on average after strengthening. A more uniform lateral load distribution factor curve was realized, indicating a better working performance of the whole system. The study confirmed that the proposed method is practical and reliable for the rehabilitation of HCSB bridges.

• 
• Supplemental Notes:
  • This paper was sponsored by TRB committee AFF10 General Structures.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Jin, Hui
  • Jiang, Hanwan
  • Jiang, Ruinian
  • Zhang, Jinquan
• Conference:
  • Transportation Research Board 94th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2015-1-11 to 2015-1-15
• Date: 2015

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; Photos; References; Tables;
• Pagination: 13p
• Monograph Title: TRB 94th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Bridge anchorages; Bridge decks; Concrete; Field tests; Finite element method; Joints; Load tests; Rehabilitation; Steel
• Geographic Terms: China
• Subject Areas: Bridges and other structures; Design; Highways; Maintenance and Preservation; I24: Design of Bridges and Retaining Walls; I61: Equipment and Maintenance Methods;

Filing Info

• Accession Number: 01551437
• Record Type: Publication
• Report/Paper Numbers: 15-3081
• Files: TRIS, TRB, ATRI
• Created Date: Jan 27 2015 11:23AM