scholarly journals Nondestructive Wireless Monitoring of Early-Age Concrete Strength Gain Using an Innovative Electromechanical Impedance Sensing System

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
C. P. Providakis ◽  
E. V. Liarakos ◽  
E. Kampianakis
Keyword(s):  
Concrete Strength ◽  
Strength Development ◽  
Early Age ◽  
Strength Gain ◽  
Impedance Sensing ◽  
Electromechanical Impedance ◽  
Sensing System ◽  
Cracking Control ◽  
Wireless Usb ◽  
Early Age Concrete

Monitoring the concrete early-age strength gain at any arbitrary time from a few minutes to a few hours after mixing is crucial for operations such as removal of frameworks, prestress, or cracking control. This paper presents the development and evaluation of a potential active wireless USB sensing tool that consists of a miniaturized electromechanical impedance measuring chip and a reusable piezoelectric transducer appropriately installed in a Teflon-based enclosure to monitor the concrete strength development at early ages and initial hydration states. In this study, the changes of the measured electromechanical impedance signatures as obtained by using the proposed sensing system during the whole early-age concrete hydration process are experimentally investigated. It is found that the proposed electromechanical impedance (EMI) sensing system associated with a properly defined statistical index which evaluates the rate of concrete strength development is very sensitive to the strength gain of concrete structures from their earliest stages.

Monitoring of concrete curing using the electromechanical impedance technique: review and path forward

2019 ◽  
pp. 147592171989306 ◽  
Author(s):  
Yee Yan Lim ◽  
Scott T Smith ◽  
Ricardo Vasquez Padilla ◽  
Chee Kiong Soh
Keyword(s):  
State Of The Art ◽  
Research Field ◽  
Strength Development ◽  
Early Age ◽  
Remote Monitoring System ◽  
Electromechanical Impedance ◽  
Wide Range ◽  
Impedance Technique ◽  
Technology Modeling ◽  
Early Age Concrete

The ability to monitor the strength development of early-age concrete is an important capability in the laboratory and in the field. Accurate and reliable in situ measurements can inform the appropriate time for removal of formwork and loading of structural elements, as well as determination of batch quality. The piezoelectric-based electromechanical impedance technique is emerging as a viable option for such monitoring needs. The first research articles on the topic started to appear in 2005, and since then, the research field has advanced and has grown in popularity. This article therefore presents the first state-of-the-art review of the topic to date. In this article, existing research is reviewed and sorted into key themes while critical developments as well as knowledge gaps are identified. The topics addressed range from miniaturization of hardware, methods of installation, incorporation of wireless technology, modeling, data interpretation, signal processing, influence of curing, and environmental conditions to a wide range of other practical issues. Previous studies have indicated that the electromechanical impedance technique has the potential to be developed into an autonomous and remote monitoring system, capable of predicting the strength development of early-age concrete structures in real time. An end game is therefore the realization of this capability. Appropriate comments are therefore also provided in this article about this goal. Researchers interested in venturing into this research area shall find this article a useful introduction as well as a state-of-the-art assessment. In addition, the identified research gaps can inform projects for more experienced research teams.

Embedded piezoelectric transducers based early-age hydration monitoring of cement concrete added with accelerator/retarder admixtures

2020 ◽  
pp. 1045389X2096991 ◽  
Author(s):  
Demi Ai ◽  
Chengxing Lin ◽  
Hongping Zhu
Keyword(s):  
Heat Effect ◽  
Hydration Heat ◽  
Strength Development ◽  
Early Age ◽  
Strength Gain ◽  
Element Analysis ◽  
Electromechanical Impedance ◽  
Hardening Process ◽  
Concrete Hydration ◽  
Early Age Hydration

Accelerator/retarder admixtures are often added into concrete to improve its early-age strength, which needs to be effectively monitored during its hardening process. The electromechanical impedance (EMI) technique has validated its effectiveness for concrete hydration monitoring, this study attempted to extend the EMI technique to monitor 28-day age of strength gain in concrete that added with accelerator/retarder admixtures. Two types of new piezoelectric (PZT) transducers namely cement/aluminum embedded PZT (CEP/AEP) were proposed for EMI monitoring. The feasibility of the CEP and AEP was first verified via finite element analysis, where hydration heat effect on the two types of transducers was comparatively evaluated by numerical modeling. In the experiment, CEP/AEP transducers were applied to monitor the strength gain in concrete cubes, where characteristics of EMI signature and its statistical indices including root mean square deviation (RMSD) and mean absolute percentage deviation (MAPD) were analyzed and correlated to strength development in concrete. Monitoring results demonstrated that concrete hydration triggered by retarder/accelerator were successfully captured by EMI signature. RMSD and MAPD indices further indicated that AEP had preferable performance than CEP transducer for monitoring early-age strength gain of concrete, as it could immune from hydration heat effect.

Nondestructive Curing Monitoring of Early-Age Concrete Using Rayleigh Wave Velocity

2006 ◽  
Vol 321-323 ◽  
pp. 318-321 ◽  
Author(s):  
Sung Woo Shin ◽  
Chung Bang Yun
Keyword(s):  
Rayleigh Wave ◽  
Wave Velocity ◽  
Strong Relationship ◽  
Strength Development ◽  
Early Age ◽  
Strength Gain ◽  
Curing Conditions ◽  
Rayleigh Wave Velocity ◽  
Series Of Experiments ◽  
Early Age Concrete

A modified one-sided Rayleigh wave (R-wave) velocity measurement technique is applied to monitor the strength gain of early-age concrete. A series of experiments were performed on early-age concrete specimens with various curing conditions. The results show that the R-wave velocity and strength gain has a strong relationship and that the R-wave velocity can be effectively used to monitor the strength development of the early-age concrete.

scholarly journals A Study on Relationship Between the Heat Release of Later-age Concrete and the Concrete Strength Development

2016 ◽  
Vol 10 (1) ◽  
pp. 363-368 ◽  
Author(s):  
Zhenyang Zhu ◽  
Weimin Chen ◽  
Zhiqiang Xie ◽  
Guoxin Zhang
Keyword(s):  
Heat Release ◽  
Temperature Rise ◽  
Concrete Strength ◽  
Adiabatic Temperature ◽  
Hydration Heat ◽  
Strength Development ◽  
Early Age ◽  
Testing Device ◽  
Adiabatic Temperature Rise ◽  
Early Age Concrete

The adiabatic temperature rise of early-age concrete can be precisely tested by the device. However, the insufficient accuracy of testing device can lead to inaccurate measurements of adiabatic temperature rise of later-age concrete. The purpose of this paper is to create a model to predict the hydration heat of later-age concrete. Based on the previous studies, it is known that the heat release of the concrete is accomplished with the increment of the concrete strength and concrete strength can be accurately measured. Thus, a preliminary later-age hydration heat model was established. The correction of the model was verified through experiments.

Resistance Analysis of Reinforced Concrete Structures in Construction

2011 ◽  
Vol 368-373 ◽  
pp. 1535-1538
Author(s):  
Nan Zhao ◽  
Wen Yan
Keyword(s):  
Concrete Strength ◽  
Early Time ◽  
Reduction Factor ◽  
Resistance Force ◽  
Early Age ◽  
Time Varying ◽  
Structural Components ◽  
Utilization Coefficient ◽  
Flexural Member ◽  
Early Age Concrete

This paper analyses the characteristics of resistance of structural components, puts forward the concept of early resistance force of structural components, and discuss the main factors which affect it based on the field measurement investigation and theoretical analysis. Besides, in the paper the reduction factor is applied to reflect time-varying features of early-age concrete strength, and utilization coefficient of concrete strength is utilized to present the influence of early time-varying features of cohesive action on resistance. The paper finally deduces the formula of early-age resistance force of typical flexural member, and gives the time-changing law of early resistance by using a case.

The Effect of Eggshell Powder as an Accelerator for Blended Cement Concrete

2020 ◽  
Vol 17 (2) ◽  
pp. 1032-1036
Author(s):  
Nur Nadhira Abdul Rasid ◽  
Abdul Rahman Mohd. Sam ◽  
Azman Mohamed ◽  
Nor Hasanah Abdul Shukor Lim ◽  
Zaiton Abdul Majid ◽  
...  
Keyword(s):  
Calcium Oxide ◽  
Palm Oil ◽  
Concrete Strength ◽  
Strength Development ◽  
Early Age ◽  
Palm Oil Fuel Ash ◽  
Fuel Ash ◽  
Early Strength ◽  
Oil Fuel ◽  
Silica Oxide

Blended concrete has later strength development with long maturity strength development. An accelerator is thus needed to enhance the early strength development of concrete. This paper shows the combination of ground palm oil fuel ash and eggshell powder that was designed for later and early strength development, respectively. Two types of eggshell powder were utilised in concrete: uncarbonised eggshell powder and decarbonised eggshell powder. The study was initiated with compression test for concrete curing at age 1, 3, 7, and 28 days followed by rapid evaluation test of setting time to investigate the preliminary performance between materials. The results revealed decarbonised eggshell powder as a high accelerator that can improve the early age of concrete strength development. Meanwhile, despite showing the best performance, uncarbonised eggshell powder is a very low accelerator thus not fit the purpose. In conclusion, the combination of ground palm oil fuel ash (rich with silica oxide) and decarbonised eggshell powder (rich with calcium oxide) provided dual function, where ground palm oil fuel ash and decarbonised eggshell powder took later and early strength development, respectively. The combination between silica oxide and calcium oxide in cementitious materials has potential to be utilised to enhance the early age of a blended concrete strength development.

Sign in / Sign up

Export Citation Format

Share Document