Zhuojin Pipe Fitting Co., LtdPushover Test Research on Masonry Structures Constrained by Steel Tube Bundle Shear Walls
Literature Overview
This paper by Chen Yong, Li Yongquan, Xie Zhonglei, Qian Kuangliang, Zhang Yesheng, Cheng Pengyun, and Ye Xuanzuo, published in the Journal of Zhejiang University (Engineering Science) in 2020 (Volume 54, Issue 3, pages 499-511), presents experimental and numerical research on masonry structures constrained by steel tube bundle shear walls. The research was supported by the National Key Research and Development Program (2017YFC0703305).
Core Technical Content
The study designed and fabricated two test specimens of steel tube bundle shear wall-masonry structures with different edge members, and conducted pushover tests to evaluate their seismic performance. Detailed finite element models were developed to analyze the mechanical behavior under horizontal loading.
Test Specimen Configuration
| Specimen | Edge Member Type | Steel Tube Bundle Configuration | Masonry Type |
|---|---|---|---|
| Specimen 1 | Type A edge member | Multiple steel tubes bundled | Brick masonry |
| Specimen 2 | Type B edge member | Multiple steel tubes bundled | Brick masonry |
Key Experimental Findings
- The masonry structure exhibits a characteristic failure pattern: initial separation from surrounding constraints, followed by diagonal crack formation and eventual failure
- The masonry structure demonstrates a clear diagonal strut effect
- The three-strut model with appropriate parameters accurately reflects the force characteristics of masonry structures under lateral loading
- The single-strut model is insufficient for capturing the actual behavior
Finite Element Analysis
The refined finite element models validated the experimental observations and provided insights into:
- Stress distribution in the steel tube bundle
- Masonry-crack propagation patterns
- Load-displacement relationship
- Energy dissipation mechanisms
Engineering Practice Integration
From a steel pipe manufacturing and welding perspective, the steel tube bundle shear wall system presents unique technical requirements:
Steel Tube Bundle Fabrication
The bundle configuration requires multiple steel tubes to be arranged and connected in a specific pattern:
- Tubes must have consistent dimensions to ensure uniform load distribution
- Spacing between tubes must be controlled for proper concrete or mortar infill
- Connections between tubes must maintain structural integrity while allowing for thermal expansion
Welding Requirements
| Welding Location | Process | Key Requirements |
|---|---|---|
| Tube-to-tube connections | FCAW or SAW | Full penetration, distortion control |
| Bundle-to-edge member | SMAW or FCAW | High strength, fatigue resistance |
| Base plate connections | SAW | Full penetration, residual stress minimization |
| Lateral restraint welds | SMAW | Consistent weld size, no burn-through |
Quality Control Considerations
The steel tube bundle shear wall is a critical seismic component, and its performance depends heavily on welding quality:
- All welds should be 100% inspected using UT or RT
- Welding procedures should be qualified per relevant standards (GB/T 19866, ISO 15614)
- Post-weld heat treatment may be required for high-strength applications
- Dimensional accuracy of the bundle assembly is critical for proper installation
Key Questions and Reflections
The research highlights the importance of edge member design in steel tube bundle shear wall-masonry systems. The different failure patterns observed between the two specimen types suggest that the edge member configuration significantly influences the overall structural behavior.
From a manufacturing perspective, the steel tube bundle system requires careful consideration of constructability. The bundle must be fabricated in sections that can be transported and assembled on site, which imposes constraints on individual section dimensions and connection details.
The finding that the three-strut model accurately captures the masonry behavior has important implications for structural analysis and design. Engineers should use this model for seismic design of masonry structures with steel tube bundle shear walls, as the simpler single-strut model may lead to unsafe designs.
Study Insights and Implications
This research contributes to the understanding of hybrid masonry-steel tube systems for seismic retrofitting and new construction. The steel tube bundle shear wall provides significant lateral force resistance and energy dissipation capacity, making it suitable for seismic zones.
For the steel pipe industry, this application represents an emerging market for structural steel tubes in building construction. The requirements for steel tube bundle shear walls are similar to those for steel tube concrete columns but with additional considerations for the bundle configuration and edge member connections.
The practical implication is that steel pipe manufacturers should develop standardized connection details for steel tube bundle applications, including prefabricated connection plates, splice details, and anchorage systems. These standardized components can reduce fabrication complexity and improve construction efficiency while ensuring consistent quality.
The research also emphasizes the importance of construction quality control. The performance of the masonry-steel tube bundle system depends on proper installation of both the steel tube bundle and the masonry infill. Any gaps or voids in the masonry can significantly reduce the system's effectiveness, highlighting the need for strict construction supervision and quality inspection protocols.