Investigating Performance of High-Rate GNSS-PPP and PPP-AR for Structural Health Monitoring: Dynamic Tests on Shake Table

Abstract

This paper investigates the usability of the GNSS PPP methods, traditional PPP with a floatambiguity solution and with Ambiguity Resolution (PPP-AR), in structural health monitoring applications based on experimental tests using a single-axis shaking table. To evaluate the performance of the PPP methodologies, harmonic oscillations of the motion table with amplitudes ranging from 5 mm to 20 mm and frequency between 0.2 Hz and 2.5 Hz were generated representing a wide range of possible structural motions. In addition, ground motion similar to those experienced during a real earthquake, the Kobe (1995), and step motions were generated on the shaking table. GNSS-PPP-derived positioning results were compared, in both of the frequency and time domains, with reference data comprising LVDT (Linear Variable Differential Transformer) data and relative positioning data. Results show that both PPP methods' measurements can be used in the computation of the harmonic oscillations' frequencies compared to the LVDT and relative positioning values. The observed amplitudes of the harmonic oscillations are slightly different from the LVDT values in the order of millimeters. Results of step motion experiment demonstrated that PPP-AR is better than traditional PPP in exhibiting the quasi-static or static displacement offsets. In addition, the capability of PPP-AR method is evaluated to the natural frequency of a small-scale structural model excited on the shaking table. The frequency spectrum of this small-scale structural model derived from the PPP-AR method is consistent with FEM (Finite Element Model) predicted value. All results demonstrate the potential of the high-rate GNSS PPP methods to reliably monitor structural and earthquake-induced vibration frequencies and amplitudes for both the structural and seismological applications.

Aging of ground Global Navigation Satellite System oscillators

“…GNSS (Global Navigation Satellite System) clocks are the core of navigation and positioning, where it is very important to ensure continuous and reliable operation in a wide range of applications, e.g. autonomous vehicles [8], dynamic displacements [26] or real-time positioning [25] and many others [12]. As research shows it has a main impact on the inaccuracy of results if clock are modelled incorrectly [5,7,13,17].…”

Investigating the effect of observation interval on GPS, GLONASS, Galileo and BeiDou static PPP

“…PPP is a powerful tool for many scientific research, such as atmospheric and ionospheric studies (Ge et al 2021a;Ma and Verhagen, 2020;Wang et al 2020), monitoring of deformation, tectonic and earthquake activities (Vazquez-Ontiveros et al 2020;Alcay et al 2019;Mendoza et al 2012), geophysical studies (Geng et al 2017) and, time transfer (Ge et al 2020). One of the most important aspects of PPP compared with the precise differential positioning is that positioning accuracy of mm to cm can be obtained using a single receiver in the static and kinematic modes, respectively (Yigit et al 2021;Yigit et al 2014;Alcay and Turgut 2021). However, the convergence time in PPP still poses a challenging problem.…”

“…High-rate GNSS positioning (with frequency of 1 Hz or higher) has become possible following the evolution of the GNSS receivers, and has been used effectively in GPS seismology (Xu et al 2013), structural health monitoring (Yigit et al 2021), and the detection of dynamic displacements (Paziewski et al 2018).…”

Yüksek zamansal çözünürlüklü çoklu-GNSS PPP-AR yönteminin yatay yönlü dinamik davranışları tespit edebilme yeteneğinin değerlendirilmesi

“…Yigit vd. [39] GPS/GLONASS uydu kombinasyonlarına dayalı PPP-AR ve geleneksel-PPP tekniklerinin dinamik davranışları belirleyebilme kabiliyetini araştırmış ve PPP-AR tekniğinin geleneksel-PPP tekniğine olan üstünlüğünü açıkça ifade etmişlerdir.…”

“…Mevcut literatür incelendiğinde görülmektedir ki, kısa süreli dinamik davranışların tespiti çalışmalarında PPP-AR tekniğinin performansı oldukça az incelenmiştir. Buna ek olarak yukarıda tartışılan çalışmalardan Yigit vd [39] hariç çoğu, genellikle 1 Hz örneklem aralığına sahiptir ve bu durum 1 Hz örneklem aralığından daha sık bir zamansal çözünürlükte PPP-AR tekniğinin 0.5 Hz'den daha yüksek frekans değerine sahip yapı hareketlerini veya kuvvetli yer hareketlerinden kaynaklanan deprem dalgalarını yakalama kabiliyetinin araştırılması gereken bir alan olduğunu göstermektedir. Ayrıca erişilen literatür çalışmalarında PPP-AR tekniğinin yapı sağlığı izlemeleri alanındaki etkinliği GPS/GLONASS uydu kombinasyonuna dayalı olarak incelenmiş, Galileo uydu takımyıldızının geleneksel-PPP ve PPP-AR tekniklerine olan katkısından henüz söz edilmemiştir.…”