Issue 73

Z. Xiong et alii, Fracture and Structural Integrity, 73 (2025) 267-284; DOI: 10.3221/IGF-ESIS.73.18

The force diagram of the joint in the limit state is demonstrated in Fig.24. The failure mode of the joint is assumed to be crushed concrete under the steel girder, and the other failure modes are not discussed this time. This requires ε b < 0.003 in the limiting state. Under this condition, ε b of alternative Eq. (4) can obtain c / l e ＞ 0.5.

Figure 24: Force transferring diagram in the limit state.

The stress-strain relationship of concrete is assumed to be:

(5)

s

The bending capacity of the steel girder-concrete joint is assumed to be the sum of the bending moment contribution of the bearing action and the bending moment contribution of the connector, namely: M u =P u (a+c)=M c +M s (6) D ETERMINATION OF THE ROTATION CENTER s shown in Fig. 24, the horizontal and vertical point lines are the parts where the vertical and horizontal relative displacements of steel girder and concrete abutment are zero respectively, and the center of deformation and rotation O is defined as the intersection point of these two lines. The balance equation combining vertical direction and horizontal direction in the ministry is as follows: A

(7)

Make λ = c/l e , μ = a/l e Previous studies have concluded that:

(8)

When λ≥0.6 ，

(9)

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