6 research outputs found
In-Pavement Fiber Bragg Grating Sensor for Vehicle Counting
Traffic volume studies are conducted to determine the number, movements, and
classifications of roadway vehicles at a given location and period. Typically, there are
two methods for conducting traffic volume studies: manual and automatic counting.
When manual counting is used, a person records the traffic volume on the site or
alternatively from video recordings and this estimate can have a large margin of error.
Automatic counting is based on measurement technologies, including pneumatic road
tubes, inductive loops, infrared, microwave Doppler/radar, passive acoustic, video
image detection, and Bluetooth devices. However, they are costly to install and have
various limitations, such as high maintenance cost, availability of power source, and
dependence on surrounding environment. Currently, weigh-in-motion (WIM) technology
has become popular for automatic vehicle counting. In this paper, a three-dimensional
glass fiber-reinforced polymer packaged fiber Bragg grating sensor (3-D GFRP-FBG) is
introduced for in-pavement vehicle counting. The 3D GFRP-FBG sensor was installed
on I-94 freeway, at MnROAD facility, Minnesota. When a vehicle passes over the road,
the pavement produces strain signals that are picked up by wavelength changes. These
strain peaks can be tracked to achieve vehicle counting. The sensors were laid out 9 feet
from the road centerline with 16 feet distance between them to detect all the vehicles
travelling on the right side of the road. The feasibility tests show the ability of the sensors
to detect vehicles from small cars to semi tractor-trailer. For a 250-second period, the
sensor detected 23 vehicles, with a total of 69 axles
Using Custom Fiber Bragg Grating-Based Sensors to Monitor Artificial Landslides
Four custom fiber Bragg grating (FBG)-based sensors are developed to monitor an artificial landslide located in Nanjing, China. The sensors are composed of a rod and two FBGs. Based on the strength of the rods, two sensors are referred to as “hard sensors” (Sensor 1 and Sensor 2), the other two are referred to as “soft sensors” (Sensor 3 and Sensor 4). The two FBGs are fixed on each sensor rod at distances of 50 cm and 100 cm from the top of the rod (an upper FBG and a lower FBG). In the experiment presented in this paper, the sensors are installed on a slope on which an artificial landslide is generated through both machine-based and manual excavation. The fiber sensing system consists of the four custom FBG-based sensors, optical fiber, a static fiber grating demodulation instrument (SM125), and a PC with the necessary software. Experimental data was collected in the presence of an artificial landslide, and the results show that the lower FBGs are more sensitive than the upper FBGs for all four of the custom sensors. It was also found that Sensor 2 and Sensor 4 are more capable of monitoring small-scale landslides than Sensor 1 and Sensor 3, and this is mainly due to their placement location with respect to the landslide. The stronger rods used in the hard sensors make them more adaptable to the harsh environments of large landslides. Thus, hard sensors should be fixed near the landslide, while soft sensors should be placed farther away from the landslide. In addition, a clear tendency of strain variation can be detected by the soft sensors, which can be used to predict landslides and raise a hazard alarm
Using Custom Fiber Bragg Grating-Based Sensors to Monitor Artificial Landslides
Four custom fiber Bragg grating (FBG)-based sensors are developed to monitor an artificial landslide located in Nanjing, China. The sensors are composed of a rod and two FBGs. Based on the strength of the rods, two sensors are referred to as “hard sensors” (Sensor 1 and Sensor 2), the other two are referred to as “soft sensors” (Sensor 3 and Sensor 4). The two FBGs are fixed on each sensor rod at distances of 50 cm and 100 cm from the top of the rod (an upper FBG and a lower FBG). In the experiment presented in this paper, the sensors are installed on a slope on which an artificial landslide is generated through both machine-based and manual excavation. The fiber sensing system consists of the four custom FBG-based sensors, optical fiber, a static fiber grating demodulation instrument (SM125), and a PC with the necessary software. Experimental data was collected in the presence of an artificial landslide, and the results show that the lower FBGs are more sensitive than the upper FBGs for all four of the custom sensors. It was also found that Sensor 2 and Sensor 4 are more capable of monitoring small-scale landslides than Sensor 1 and Sensor 3, and this is mainly due to their placement location with respect to the landslide. The stronger rods used in the hard sensors make them more adaptable to the harsh environments of large landslides. Thus, hard sensors should be fixed near the landslide, while soft sensors should be placed farther away from the landslide. In addition, a clear tendency of strain variation can be detected by the soft sensors, which can be used to predict landslides and raise a hazard alarm
International Conference on Civil Infrastructure and Construction (CIC 2020)
This is the proceedings of the CIC 2020 Conference, which was held under
the patronage of His Excellency Sheikh Khalid bin Khalifa bin Abdulaziz Al
Thani in Doha, Qatar from 2 to 5 February 2020. The goal of the conference
was to provide a platform to discuss next-generation infrastructure and its
construction among key players such as researchers, industry professionals
and leaders, local government agencies, clients, construction contractors and
policymakers.
The conference gathered industry and academia to disseminate their research
and field experiences in multiple areas of civil engineering. It was also a unique
opportunity for companies and organizations to show the most recent
advances in the field of civil infrastructure and construction.
The conference covered a wide range of timely topics that address the needs
of the construction industry all over the world and particularly in Qatar. All
papers were peer reviewed by experts in their field and edited for publication.
The conference accepted a total number of 127 papers submitted by authors
from five different continents under the following four themes:
Theme 1: Construction Management and Process
Theme 2: Materials and Transportation Engineering
Theme 3: Geotechnical, Environmental, and Geo-environmental Engineering
Theme 4: Sustainability, Renovation, and Monitoring of Civil InfrastructureThe list of the Sponsors are listed at page 1