Analysis of the Generating and Influencing Factors of Vertical Cracking in Abutments during Construction

Abstract EN

In order to analyze the causes of cracking in abutments subject to concrete shrinkage and temperature variation during the construction process and to determine factors affecting the mechanical properties of the abutment, nonlinear calculations capturing abutment behavior are conducted with Midas/FEA software.

Using these calculations, the cracking mechanism is identified, and the influence of the evaluated factors is analyzed.

It is concluded that the deformation between the pile cap and abutment backwall as constrained by a pile foundation when subjected to concrete shrinkage and temperature changes is the basic cause of abutment cracks during construction; these cracks form over the piles and develop upward.

For a given reinforcement ratio, the distribution of horizontal crack-control steel using small, closely spaced bars is more beneficial.

When pile-bearing capacity meets the standard, the width of the generated cracks tends to decrease with the decrease in the diameter of the piles.

The existence of a postcast strip in the abutment backwall also contributes to the decrease in the depth of the crack.

Finally, the impact of age difference between the pile cap concrete and abutment backwall concrete on cracking is inconsequential.