| Title |
A Study on the Determination of Slip-up Time for Slip-Form System using Surface Wave Velocity |
| Authors |
김희석(Kim, Heeseok) ; 김영진(Kim, Young Jin) ; 진원종(Chin, Won Jong) ; 윤혜진(Yoon, Hyejin) |
| DOI |
https://doi.org/10.12652/Ksce.2012.32.5D.483 |
| Keywords |
슬립폼 시스템;초기경화시간;표면파 속도;연속웨이블릿변환 setting time;slip-form system;surface wave velocity;continuous wavelet transform |
| Abstract |
The early setting time of concrete is an important factor determining the slip up velocity of the slip-form system. Accordingly, need is for a technique evaluating the early setting time in order to secure the safety of the slip-form system and the construction quality of concrete. This paper intends to estimate the early setting time by evaluating the setting degree of concrete using surface wave velocity so as to determine the slip up time of the slip-form system. Penetration resistance test and compressive strength test are performed first to clarify the relationship between the early setting time of concrete and the compressive strength. Then, compressive strength test and ultrasonic wave test are conducted to examine the relation between the compressive strength and the surface wave velocity. Continuous wavelet transform is adopted to measure the surface wave velocity. Numerical analysis is carried out to demonstrate the appropriateness of the application of continuous wavelet transform. Based on these results, the propagation velocity of the surface wave required for the slip up of slip-form system is suggested. Finally, a reduced model test of the slip-form system is conducted to verify the feasibility of the proposed surface wave velocity for the determination of th slip up velocity. |