Geotechnical Engineering Monitoring Research Articles

Comprehensive calibration and laboratory validation of a micro electromechanical system sensor-based flexible inclinometer

Abstract Real-time monitoring of slopes, tunnels, and dams is important for ensuring the long-term stability and reliability of such structures. Despite the successes of current technologies in many applications, a gap still exists in certain areas such as precision in steep slopes and complex soil conditions. This study has designed a flexible inclinometer based on an array of Micro Electromechanical System (MEMS) sensors to enhance the accuracy and flexibility of existing monitoring techniques. The inclination angle of each flexible inclinometer measurement unit was measured to monitor the horizontal or vertical displacement of the target structural body. We used the Levenberg–Marquardt (LM) algorithm for optimizing the MEMS sensors based calibration and designed multiple experiments to test the accuracy of the proposed method. Experimental results show that the calibrated flexible inclinometer measurement unit has an inclination angle of less than 0.04° and the accuracy of the flexible inclinometer lies within ±0.4 mm in the horizontal attitude and 1.6 mm in the vertical attitude. Our research has developed a novel tool for geotechnical engineering monitoring that can aid in increasing the precision of real-time assessment and prediction of structural stability.

Appraisal of rock IR law and damage precursor: Insight infrared thermogram entropy

During the process of force deformation, the rock will be destabilized and damaged, and a deep understanding of the rock rupture precursors is a crucial foundation for early warning of mine hazards, including mine water inrush and surrounding rock destabilization. This study investigates the properties of infrared radiation (IR) and the precursors of rupture in the process of rock fracture using a novel thermal infrared analysis method called index-infrared image entropy (IE). The IE variation mechanism is discussed together with the frequency histogram of infrared images. The results highlight that IE may be used to characterize the IR information of rock during the pre-peak loading period. The IE value increases rapidly during the pre-peak loading period, then increases slowly and eventually tends to stabilize. Pre-peak stress and IE are correlated using a logarithmic function. The rock enters the plastic stage when the change in IE reaches 2.78, which may be utilized as a precursor threshold of bearing rock failure. At this point, the precursor stress level is 0.93σmax. In addition, abnormal IR histogram changes from a single peak to a double peak form may serve as a crucial precursor to bearing rock failure. The study's findings are useful for mining and geotechnical engineering monitoring and early warning of nearby rock instability and mine water inrush.

Comparative In Situ Study of Dynamic Load Generated by Gravel Piles Measured by a Fiber-Optic Interferometer.

Currently, all the technology used for seismic monitoring is based on sensors in the electrical domain. There are, however, other physical principles that may enable and fully replace existing devices in the future. This paper introduces one of these approaches, namely the field of fiber optics, which has great potential to be fully applied in the field of vibration measurement. The proposed solution uses a Michelson fiber-optic interferometer designed without polarization fading and with an operationally passive demodulation technique using three mutually phase-shifted optical outputs. Standard instrumentation commonly used in the field of seismic monitoring in geotechnical engineering was used as a reference. Comparative measurements were carried out during the implementation of gravel piles, which represents a significant source of vibration. For the correlation of the data obtained, the linear dependence previously verified in laboratory measurements was used. The presented results show that the correlation is also highly favorable (correlation coefficient in excess of 0.9) from the values measured in situ, with an average deviation for the oscillation velocity amplitude of the optical sensor not exceeding 0.0052.

Applications of distributed opto-electronic sensing technologies in geotechnical engineering monitoring

This paper summarizes the application status of distributed optical fiber sensing technology in the main fields of geotechnical engineering monitoring in China and Far Eastern Russia, including pile foundation engineering, foundation pit engineering, slope engineering, tunnel and bridge engineering monitoring.

Geotechnical Engineering Intelligent Monitoring and Controlling System and its Application in Pit Engineering

The shortages and drawbacks of traditional geotechnical engineering monitoring and controlling system(GEMCS) is reviewed and the necessity and inevitability to establish a modern GEMCS are argued and discussed sufficiently. Modern GEMCS are fundamentally divided into two subsystems, remote management subsystem and site management subsystem respectively. Each of the subsystems is introduced and described subsequently by their components, main functions and capability in solving issues. Then, the predominant characteristics and advantages of the modern GEMCS are specified with two facets: components features and unlimited time-spatial domain monitoring. Applications in deep pit constructions are illustrated to visualize the functions of the modern GEMCS, followed by three research strategies of scholars from home and abroad are analyzed and summed up. Last, based on two levels, which are completions and evolutions of monitoring and controlling system itself as well as its generalizations in applications and promotions in geomechanics, developments supposed to achieve in modern intelligent GEMCS in 21st century are prospected and forecasted.

Advances in Instrumentation and Monitoring in Geotechnical Engineering

[Extract] Geotechnical instrumentation to monitor the performances of earth and earth-supported structures is increasingly becoming popular. Verification of long-term performances, validation of new theories, construction control, warning against any impending failures, quality assurance, and legal protection are some of the many reasons for geotechnical instrumentation. They are not only used in field situations, but in laboratories too. With the recent advances in materials and technology, and the need for more stringent performance control, there had been significant developments in the recent past in instrumentation and monitoring techniques.

Interactive computer aided methods for the design and monitoring of embankment dams : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986P747–765. Publ Bangkok: AIT, 1986

Interactive computer aided methods for the design and monitoring of embankment dams : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986P747–765. Publ Bangkok: AIT, 1986

Design of a tunnel with 9.7m diameter in tertiary clay : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P648–660. Publ Bangkok: AIT, 1986

Design of a tunnel with 9.7m diameter in tertiary clay : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P648–660. Publ Bangkok: AIT, 1986

Prediction of horizontal behaviour of pier foundations : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P547-561. Publ Bangkok: AIT, 1986

Prediction of horizontal behaviour of pier foundations : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P547-561. Publ Bangkok: AIT, 1986

Interactive finite element mesh generation for three dimensional tunnel analysis : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986P609–628. Publ Bangkok: AIT, 1986

Interactive finite element mesh generation for three dimensional tunnel analysis : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986P609–628. Publ Bangkok: AIT, 1986

Analytical requirement for the simulation of shallow sandy ground tunnel : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P661–671. Publ Bangkok: AIT, 1986

Analytical requirement for the simulation of shallow sandy ground tunnel : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P661–671. Publ Bangkok: AIT, 1986

Strain analysis of jointed rock masses for monitoring the stability of underground openings : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P599–608. Publ Bangkok: AIT, 1986

Strain analysis of jointed rock masses for monitoring the stability of underground openings : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P599–608. Publ Bangkok: AIT, 1986

Boundary element method for determining stresses around openings in non-homogeneous rock media : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P629–647. Publ Bangkok: AIT, 1986

Boundary element method for determining stresses around openings in non-homogeneous rock media : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P629–647. Publ Bangkok: AIT, 1986

Special problems in the computer aided analysis of underground structures : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986P727–746. Publ Bangkok: AIT, 1986

Special problems in the computer aided analysis of underground structures : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986P727–746. Publ Bangkok: AIT, 1986

Computer design and analysis of pile caps and spread footings : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P532-546. Publ Bangkok: AIT, 1986

Computer design and analysis of pile caps and spread footings : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P532-546. Publ Bangkok: AIT, 1986

Face stabilization control of earth pressure type shield : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P698–726. Publ Bangkok: AIT, 1986

Face stabilization control of earth pressure type shield : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P698–726. Publ Bangkok: AIT, 1986

Nonlinear excavation analysis through the finite element activity concept : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P672–684. Publ Bangkok: AIT, 1986

Nonlinear excavation analysis through the finite element activity concept : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P672–684. Publ Bangkok: AIT, 1986

Computer aided bound solutions in a cohesive material : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P685–697. Publ Bangkok: AIT, 1986

Computer aided bound solutions in a cohesive material : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P685–697. Publ Bangkok: AIT, 1986

Computer aided desining, detailing, and drafting of transmission line tower foundations : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P562-574. Publ Bangkok: AIT, 1986

Computer aided desining, detailing, and drafting of transmission line tower foundations : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P562-574. Publ Bangkok: AIT, 1986

Note on the use of rigid-plastic analysis : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P591–598. Publ Bangkok: AIT, 1986

Note on the use of rigid-plastic analysis : Proc Symposium on Computer Aided Design and Monitoring in Geotechnical Engineering, Bangkok, 3–6 December 1986 P591–598. Publ Bangkok: AIT, 1986