Zhuojin Pipe Fitting Co., LtdConstruction Simulation and Optimization of Super-High-Rise CFST Frame-Tube Structures
Literature Overview and Research Context
The paper by Mao Shiyang, Yan Weiming, Jia Hong, Ma Yubin, and Xie Zhicheng from Beijing University of Technology and China Railway Construction Engineering Group presents a comprehensive construction simulation analysis and scheme optimization for a super-high-rise concrete-filled steel tube (CFST) frame-tube structure. Published in Construction Technology in 2016, this research addresses the practical challenges of constructing tall buildings where construction sequence effects, material time-dependent behavior, boundary conditions, and pile foundation settlement significantly influence structural performance.
Core Technical Content
The researchers utilized the SAP2000 finite element program to simulate the construction process using the element birth-death method, which accurately captures the progressive activation of structural members as construction proceeds floor by floor. The simulation considered the time-varying nature of material properties, boundary conditions, and load actions, as well as the influence of pile foundation settlement.
Key research outcomes include:
- Analysis of vertical deformation differences during the construction phase across different construction stages.
- Investigation of internal force distribution patterns and their evolution with construction progress.
- Evaluation of different construction conditions and schemes on internal forces and deformations of the CFST frame-tube hybrid structure.
- Identification of the optimal construction scheme based on comprehensive performance criteria.
- Calculation of pre-adjustment values for vertical load-bearing members based on vertical deformation analysis results.
| Analysis Aspect | Method | Key Finding |
|---|---|---|
| Construction simulation | Element birth-death in SAP2000 | Accurate representation of progressive construction |
| Vertical deformation | Time-dependent analysis | Significant variation across construction stages |
| Internal force distribution | Stage-by-stage analysis | Force redistribution with each new floor |
| Pile settlement effect | Boundary condition modeling | Non-uniform settlement affects member forces |
| Pre-adjustment values | Deformation-based calculation | Essential for achieving design elevations |
| Scheme optimization | Multi-criteria comparison | Optimal sequence identified for balanced performance |
Engineering Practice Implications
This research is directly relevant to the construction of tall buildings, where CFST columns and beams are widely used for their high strength-to-weight ratio and ductility. The element birth-death method in finite element analysis is a standard technique for construction sequence simulation, but the accuracy of results depends on proper modeling of time-dependent effects such as concrete creep and shrinkage, as well as the progressive application of construction loads.
For steel pipe and pipe fitting suppliers involved in super-high-rise projects, this research highlights several practical considerations:
- Member fabrication tolerances: The pre-adjustment values calculated in the study indicate that members must be fabricated with specific dimensional adjustments to compensate for predicted construction-stage deformations. Steel pipe suppliers must accommodate these adjustments in their fabrication processes.
- Connection design and welding: The internal force redistribution during construction means that connections experience varying stress levels as the building rises. Welded connections in CFST frame-tube structures must be designed to accommodate both construction-stage and service-stage loading. Welding engineers should ensure that connection welds are designed for the maximum expected forces, not just the final service loads.
- Quality control during erection: The construction sequence optimization identified in the study provides a framework for quality control during erection. Inspection teams should verify that the construction sequence follows the optimized plan, as deviations can lead to unexpected internal forces and potential structural issues.
- Pile foundation settlement monitoring: The inclusion of pile settlement effects in the simulation underscores the importance of geotechnical monitoring during construction. Settlement data should be fed back into the structural model for real-time adjustment of erection procedures.
Study Reflections and Key Insights
The integration of construction simulation with scheme optimization represents a mature engineering approach that is essential for complex tall building projects. The pre-adjustment calculation methodology is particularly valuable, as it enables engineers to achieve design elevations and geometric accuracy despite the inevitable construction-stage deformations. For practitioners, this research reinforces the importance of collaborative design between structural engineers, steel fabricators, and construction teams, as the optimal construction scheme requires input from all disciplines. The element birth-death method, while computationally straightforward, demands careful calibration against known construction data to ensure reliable predictions.