Massive Concrete Engineering Introduction
The design of this project conforms to the safety requirements of proton equipment radiation prevention. The maximum thickness of structural slabs and walls reaches 3.2m and 3.5m, respectively. According to the regulations approved by the Atomic Energy Council of the Executive Yuan, the concrete quality must meet the following requirements:
A. Strength reaching 4,000Psi.
B. Slump ranging from 55 to 70cm, with a requirement to reach 50cm within 3 to 15 seconds.
C. Core surface temperature difference △t ≤ 25℃.
D. Concrete density of 2,350kg/cm3 or above.
For this project, a quality verification plan was developed in collaboration with National Taiwan University (TaiTech). It involved selecting insulation materials, concrete plant inspections and mix tests, scale tests, initial-scale tests, on-site construction, and on-site temperature control monitoring. Rigorous operations were conducted to meet the quality requirements.
Massive Concrete Quality Verification Plan
To enhance the construction quality of the massive concrete in this project, our company, in collaboration with a Ph.D. from National Taiwan University, formed a verification team. The team completed scale tests, the first-scale test, and the second-scale test, meeting the temperature difference and strength requirements specified. A Massive Concrete Quality Verification Plan was written, and the project site executed it. For all temperature control monitoring, our company engaged the third-party organization SGS to conduct the monitoring. Simultaneously, the Taiwan Provincial Civil Engineering Technician Association was enlisted to perform the quality verification and certification of the massive concrete, and the owner appointed a subsidiary company to monitor the entire process. Currently, the average core surface temperature of the massive concrete meets the specification requirements, with a temperature difference within 25℃.
Massive Concrete Engineering Construction Steps
Step 1
Concrete Plant Inspection and Mix Test
Each unit inspects and confirms the concrete mix process at the concrete plant, including proportions, slump, U-type and V-type tests, and specimen production.
Step 2
Scale Test - Model I and Model II
Two scale models were constructed on-site, and the quality verification process was checked. After demolding, the concrete core surface temperature was tracked and recorded.
Step 3
Full-scale Test - Model I and Model II (each with dimensions of 3.5m x 3.5m x 2.5m)
Based on the results of the scale test, the construction process and quality control inspection points were confirmed. Two full-scale models were then constructed on-site, repeating the confirmation of the finished results.
Step 4
On-site Temperature Control Monitoring
Based on the observed results of the test monitoring for core surface temperature differences, insulation and curing measures were removed approximately from the 5th day after on-site construction, and curing was completed by the 7th day.
