Abstract To improve the load-bearing performance of tunnel initial support structures under eccentric compres? sion, a new type of steel-concrete composite structure with double-row shear studs arranged on both sides of the steel web was proposed. Large eccentric compression tests were carried out under different eccentricities, and finite element simulations were used to analyze the load bearing characteristics of the composite structure and the influence of eccentricity variation on its performance. The results show that under natural bonding conditions, when the large eccentricity reaches 0.5h or 0.7h, cracks appear on both the compression and tension sides of the component, accompanied by concrete spalling, leading to complete failure of the structure. In contrast, the use of double-row shear studs significantly inhibits the slip at the steel-concrete interface, reduces crack propagation, and enhances the overall bearing capacity of the structure. For natural bonding components, the load-displacement curves exhibit similar trends under both 0.5h and 0.7h eccentricities, with the post-load bearing capacity maintained at 78% of the peak load. For components with double-row shear studs, the curves are also consistent, with the post-load capacity maintained at 89% of the peak load. Moreover, lateral deflection is reduced to a similar extent in both eccentricity conditions, indicating that the bearing performance and ductility of the studded members are not significantly affected by large eccentricity variations. Numerical simulations further confirm that the bearing capacity of studded composite members continues to improve with increasing eccentricity, validating the applicability of this structural form in tunnel initial support design.
Abstract：
To improve the load-bearing performance of tunnel initial support structures under eccentric compres? sion, a new type of steel-concrete composite structure with double-row shear studs arranged on both sides of the steel web was proposed. Large eccentric compression tests were carried out under different eccentricities, and finite element simulations were used to analyze the load bearing characteristics of the composite structure and the influence of eccentricity variation on its performance. The results show that under natural bonding conditions, when the large eccentricity reaches 0.5h or 0.7h, cracks appear on both the compression and tension sides of the component, accompanied by concrete spalling, leading to complete failure of the structure. In contrast, the use of double-row shear studs significantly inhibits the slip at the steel-concrete interface, reduces crack propagation, and enhances the overall bearing capacity of the structure. For natural bonding components, the load-displacement curves exhibit similar trends under both 0.5h and 0.7h eccentricities, with the post-load bearing capacity maintained at 78% of the peak load. For components with double-row shear studs, the curves are also consistent, with the post-load capacity maintained at 89% of the peak load. Moreover, lateral deflection is reduced to a similar extent in both eccentricity conditions, indicating that the bearing performance and ductility of the studded members are not significantly affected by large eccentricity variations. Numerical simulations further confirm that the bearing capacity of studded composite members continues to improve with increasing eccentricity, validating the applicability of this structural form in tunnel initial support design.
CHENG Gaojun1 HE Lidong2 WANG Kui
.Performance Analysis of Steel-concrete Composite Structures with Double-row Shear Studs under Large Eccentric Compression[J] MODERN TUNNELLING TECHNOLOGY, 2025,V62(3): 30-39
2025, Vol. 62 