Construction Control Technology for Steel Tube Concrete Tie-Arch Bridge

Literature Overview

This paper by Sun Jiuchun, Cao Hong, and Xi Guodong (2022), published in Construction Technology (Chinese and English) (Vol. 51, No. 15, pp. 67-71), documents the construction control technology applied to a steel tube concrete (CFST) tie-arch bridge project. The work was supported by Tengda Construction Group Co., Ltd. research project (2020-HZ-007). The study focuses on critical construction phases including tie beam concrete pouring, steel arch rib installation, and hanger installation, with comprehensive monitoring and comparison of measured versus theoretical values.

Core Technical Content

Construction control for CFST tie-arch bridges is inherently complex due to the staged construction sequence, the interaction between temporary and permanent structural systems, and the need to achieve precise final geometry and force states.

Critical Construction Phases

Phase	Key Activities	Critical Control Parameters
Tie beam concrete pouring	Segmental casting, formwork erection	Concrete strength, temperature control, placement sequence
Steel arch rib installation	Segmental hoisting, temporary bracing	Alignment accuracy, temporary support stiffness
Arch rib concrete filling	Concrete pumping, compaction	Fill density, void detection, bonding quality
Hanger installation and tensioning	Cable installation, incremental tensioning	Cable force accuracy, deck geometry
System conversion	Removal of temporary supports	Stress redistribution, final geometry

Monitoring and Control Strategy

The study employs a full-process tracking monitoring approach, comparing measured values with theoretical calculations for:

Tie beam: Deformation (vertical and horizontal displacement), stress (concrete and steel reinforcement), and temperature effects.
Steel arch rib: Segmental deformation, stress in steel tube, and concrete fill quality verification.
Hangers: Cable force measurements, with adjustment protocols to ensure uniform force distribution.

The comparison between measured and theoretical values serves as the basis for corrective actions during construction. Deviations beyond acceptable tolerances trigger adjustments in subsequent construction steps to ensure the final as-built state meets design requirements.

Process and Standards Analysis

Construction control for CFST bridges must comply with relevant standards including:

Standard	Scope	Relevance
JTG/T 3650	Construction quality control for highway bridges	General construction quality requirements
TB 10003	Railway bridge construction specifications	If applicable for railway bridges
GB 50204	Concrete structure construction and acceptance	Concrete placement and quality control
GB 50205	Steel structure construction and acceptance	Steel arch rib fabrication and erection
JTG F80/1	Highway bridge construction quality acceptance standards	Final acceptance criteria

The construction sequence for a CFST tie-arch bridge typically follows this logic:

Pier and abutment construction — Establish support points for the arch system.
Tie beam segmental construction — Build the tie beam in segments, controlling deflection and camber.
Steel arch rib segmental erection — Hoist and connect arch rib segments, using temporary bracing to maintain stability.
Arch rib concrete filling — Fill the steel tubes with concrete, ensuring full compaction and bonding.
Hanger installation and tensioning — Install hangers and incrementally tension to transfer deck load to the arch.
Deck construction — Build the bridge deck using the hanger-supported system.
System conversion — Remove temporary supports, transferring loads to the permanent structural system.
Final adjustment — Adjust cable forces and geometry to achieve design target state.

Integration with Engineering Practice

The construction control methodology described in this paper exemplifies best practices for complex bridge construction:

Predictive modeling: Theoretical calculations provide predicted deformation and stress values for each construction step, serving as benchmarks for monitoring.
Real-time feedback: Monitoring data is compared with predictions in real-time, enabling immediate identification of deviations and corrective action.
Iterative adjustment: Cable force adjustments and geometric corrections are applied iteratively to converge toward the design target state.
Documentation and traceability: All measurements, calculations, and adjustments are documented for quality assurance and future reference.

For the steel arch rib, the concrete filling process is particularly critical. The quality of concrete placement within the steel tube directly affects the composite action of the CFST section. Insufficient compaction leads to voids that reduce the effective cross-sectional area and create stress concentrations. Quality control measures should include:

Pre-construction concrete mix design optimization for pumpability and compaction within confined spaces.
Use of low-slump concrete with appropriate admixtures for self-compacting behavior.
In-situ density testing (e.g., ultrasonic pulse velocity method) to verify fill quality.
Thermal monitoring during concrete placement to control hydration temperature and prevent thermal cracking.

Key Questions and Reflections

The construction control approach described raises several important considerations. First, the accuracy of theoretical predictions depends on the quality of the input parameters (material properties, boundary conditions, load assumptions). Uncertainties in these parameters should be quantified and incorporated into the control strategy through sensitivity analysis. Second, the transition from temporary to permanent structural systems involves complex stress redistributions that may not be fully captured by linear elastic analysis. Third, the long-term behavior of the completed bridge—including creep, shrinkage, and thermal effects—should be considered in the construction control strategy to ensure that the as-built state evolves toward acceptable long-term performance.

From a practical standpoint, the success of construction control depends on the integration of design, construction, and monitoring teams. Communication of monitoring results and design intent must be seamless, and decision-making authority for corrective actions should be clearly defined. The use of integrated construction management software can facilitate this process by providing a unified platform for data collection, analysis, and reporting.

Study Insights and Implications

This paper provides a valuable case study of construction control technology for CFST tie-arch bridges, demonstrating the practical application of monitoring-based construction management. The systematic approach of comparing measured versus theoretical values throughout the construction process ensures that the final structure meets design requirements in terms of geometry, stress state, and structural performance. For the steel pipe industry, the study highlights the importance of dimensional accuracy in steel arch rib fabrication, as manufacturing tolerances directly affect the ease of segmental connection and the accuracy of the final arch geometry. The findings also underscore the need for close collaboration between steel pipe manufacturers, concrete suppliers, and construction contractors to ensure that material quality meets the demanding requirements of CFST bridge construction.