Session: Government Agency Student Posters

Paper Number: 173950

Development of Embedded Sensors for Real-Time Monitoring of Concrete Properties in 3d Printing 

3D printing is a promising way to address certain issues faced in manufacturing. The recent rapid development of 3D printing technology has gained significant attention from the construction industry. The benefits of 3D printing in the concrete industry are many and include faster construction time, freedom to build almost anything, reduced materials usage, minimizing environmental impact by reducing waste, and the potential of autonomous operation. However, concrete is a complex heterogenous material composed of solids, liquids, and gasses (air). Its properties change over time as a series of chemical reactions. Accurate rheology measuring methods are crucial in optimising the performance of 3D printed concrete. They enable engineers to fine-tune formulations or printing parameters, ensuring structural integrity. Conventional ways to measure the rheological properties of concrete rely on using rheometers. These only test static samples which limit their applicability in 3D printing. This proposal seeks to address this problem by adopting the multi-sensors sensing system (SMISS) that was developed in Dr. Yen-Fang Su’s (PI) lab. The system can capture several in-situ properties of 3D printable concrete at different locations in the printing device to obtain real-time rheological properties during the 3D printing process.

 

This project will build upon previous work done in Dr. Yen-Fang Su’s (PI) lab. Based on the piezoelectric effect, when a piezoelectric sensor is in contact with a host material, the sensor will “vibrate” together with the host. This produces a measurable voltage, or potential difference. The host material’s stiffness determines how restricted the “vibrating” of the piezoelectric sensors is. Hence, resulting in different admittance and phase angle spectrums. By sweeping an AC signal through a piezoelectric sensor, the electromechanical impedance (EMI) spectrum can be recorded. Changes in this spectrum can be used to deduce the stiffness of the concrete. Environmental temperature will be recorded with thermocouples, allowing us to compensate for temperature effects on the piezoelectric sensor’s response. Resonant peaks in the EMI spectrum will be mapped and tracked against concrete stiffness measurements obtained at the same time using a rheometer, establishing a calibration dataset.  

 

Using this dataset, an algorithm can then be developed to predict stiffness directly from the EMI spectrum (with temperature compensation). Ultimately, the aim is to package the sensor, excitation and capture electronics, and onboard processing into a compact SMISS prototype. Further an integrated system can be created when attaching this prototype onto a 3D concrete printer. The device will continuously monitor stiffness and automatically adjust print speed to ensure optimal layer bonding and structural performance.

Presenting Author: Ted Atera Louisiana State University

Presenting Author Biography: Ted Atera is a senior in the Department of Electrical Engineering at Louisiana State University (LSU) supported by NSF Award #2328188, "Toward Future Underwater Additive Manufacturing of Bio-Based Construction Materials Through AI-Guided Sensing and Material Modeling". His project, “Development of Embedded Sensors for Real-Time Monitoring of Concrete Properties in 3D Printing,” uses the admittance spectrum generated by excited piezoelectric sensors embedded in concrete of varying stiffness to deduce key rheological properties. Under the guidance of Dr. Yen-Fang Su (PI) and PhD student Masoud Pasbani, he’s advanced a novel technique for in situ concrete characterization. Ted presented this work at the LSU Undergraduate Research Conference (Discover Day), where it was selected among the top five presentations in the engineering department.

Authors:

Ted Atera Louisiana State University
Masoud Pasbani Louisiana State University
Yen-Fang Su Louisiana State University