Cumulative Deformation Research Articles

EVALUATION METHOD FOR CUMULATIVE PLASTIC DEFORMATION OF HYSTERETIC DAMPERS INSTALLED IN SMRF

By yielding under small inter-story deformation, hysteretic dampers installed to a response control structure absorb seismic energy and effectively control the damage to the frame. When designing such a structure, it is important to estimate the maximum deformation and the cumulative plastic deformation of the dampers against ground motions. Especially in the early stage of design, simple methods are useful for the preliminary study of determining the characteristics of the dampers. In this research, the shortcomings of the existing simple methods are discussed and a new method is proposed. Its accuracy and applicability are investigated using numerical examples.

Short and long term performance of a slab track in a transition zone: an embankment to tunnel analysis

Railway track transition zones are characterised by an abrupt change in track support stiffness, which increases dynamic wheel loads and leads to the acceleration of differential settlement and track degradation. This work aims to study concrete slab track transition zones, with a focus on embankment-to-tunnel sections. The analysis uses a hybrid methodology, combining 3D finite element modelling with empirical settlement equations, in an iterative manner. At each iteration, the track-ground stress fields are calculated using a 3D model, before passing them to a calibrated empirical equation capable of computing settlement across the transition. Then, before starting the next iteration, these settlements are used to modify the 3D model geometry, thus account for the effects of the previous settlement. Regarding the short-term dynamic behaviour, the results demonstrate a concentration of stresses in the concrete slab and HBL. Regarding the long -term behaviour, the results show a maximum cumulative permanent deformation close to 0.52 mm. Moreover, the effectiveness of a resilient mat placed in the transition was tested. The results show a decrease in the stress levels in the transition and the attenuation of the variation of displacements in the concrete slab.

Effect of Deformation Degree on Microstructure and Texture of AZ31 Magnesium Alloy in Hot Drawing

Microstructure and texture evolution of the AZ31 magnesium alloy wire under different deformation degrees was investigated by continuous hot drawing deformation. With the increase of cumulative deformation degree, the grain refinement effect is remarkable. However, there is a critical deformation degree, and excessive deformation will increase the grain size. During the deformation process of hot drawing, the dynamic recrystallization mechanism of AZ31 magnesium alloy wire changed from twin dynamic recrystallization to rotary dynamic recrystallization. With the increase of cumulative deformation, the initial {0001} <11-20> silk texture gradually changed into {0001} <10-10> silk texture.

Monitoring Method of Large Section Bifurcated Small Clear Distance Tunnel during Information Construction Control

Constructing a large section bifurcated small clear distance tunnel poses significant challenges due to its large section and small clear distance, complex and overlapping construction steps, unsynchronized excavation and support processes, and disturbance of surrounding rock caused by blasting. Timely and effective construction monitoring is crucial to ensure construction safety and quality. However, traditional monitoring methods are unable to fully satisfy requirements and realize real-time monitoring. Therefore, this study proposes an automatic monitoring and control method for a large section bifurcated small clear distance tunnel to leverage the positive role of information construction. Using the Xiamen Haicang Evacuate Channel project as a case study, this paper introduces the tunnel monitoring and layout scheme of monitoring points. The monitoring data were analyzed from different perspectives, including cumulative deformation, deformation rate, cumulative deformation control value, and deformation rate control value. The follow-up excavation and support measures were optimized based on the measurement results. Additionally, an automatic monitoring and control method of the middle rock pillar combined with the criterion of stability of the middle rock pillar was proposed, constructing a working idea and framework for timely feedback and three-dimensional and dynamic monitoring. Site monitoring predicted the danger before construction and provided feedback on construction information to improve the specific construction method of subsequent excavation and support. The proposed automatic monitoring and control method can solve the problem of accidental errors in traditional monitoring methods and enable real-time automatic monitoring. The research results provide valuable experience for constructing a bifurcated small clear distance tunnel.

Remote Sensing Monitoring and Analysis of Jinwuco Lateral Moraine Landslide-Glacial Lake Outburst in Southeast Tibet

On 25 June 2020, a glacial lake outburst flood (GLOF) occurred in Jinwuco, Nidou Zangbo, and southeast Tibet, causing catastrophic damage to multiple infrastructures such as roads, bridges, and farmlands in the surrounding and downstream areas. Due to the lack of long-term monitoring of glacial lake and glacier changes in the region and the surrounding surface, the spatial and temporal evolutionary characteristics and triggering factors of the disaster still need to be determined. Here, we combine multi-temporal optical remote sensing image interpretation, surface deformation monitoring with synthetic aperture radar (SAR)/InSAR, meteorological observation data, and corresponding soil moisture change information to systematically analyze the spatial and temporal evolution characteristics and triggering factors of this GLOF disaster. Optical images taken between 1987 and 2020 indicate that the glacial lake’s initial area of 0.39 km2 quickly grew to 0.56 km2, then plummeted to 0.26 km2 after the catastrophe. Meanwhile, we found obvious signs of slippage beside the lateral moraine at the junction of the glacier’s terminus and the glacial lake. The pixel offset tracking (POT) results based on SAR images acquired before and after the disaster reveal that the western lateral moraine underwent a 40 m line of sight (LOS) deformation. The small baseline subset InSAR (SBAS-InSAR) results from 2017 to 2021 show that the cumulative deformation of the slope around the lateral moraine increased in the rainy season before the disaster, with a maximum cumulative deformation of −52 mm in 120 days and gradually stabilized after the disaster. However, there are three long-term deformation areas on the slope above it, showing an increasing trend after the disaster, with cumulative deformation exceeding −30 mm during the monitoring period. The lateral moraine collapse occurred in a warm climate with continuous and intense precipitation, and the low backscatter intensity prior to the slide suggests that the soil was very moist. Intense rainfall is thought to be the catalyst for lateral moraine collapse, whereas the lateral moraine falling into the glacier lake is the direct cause of the GLOF. This study shows that the joint active–passive remote sensing technique can accurately obtain the spatial and temporal evolution characteristics and triggering factors of GLOF. It is helpful to understand the GLOF event caused by the slide of lateral moraine more comprehensively, which is essential for further work related to glacial lake hazard assessment.

Physical modeling of long-term dynamic characteristics of the subgrade for medium–low-speed maglevs

To investigate the dynamic characteristics and long-term dynamic stability of the new subgrade structure of medium–low-speed (MLS) maglevs, cyclic vibration tests were performed under natural and rainfall conditions, and the dynamic response of the subgrade structure was monitored. The dynamic response attenuation characteristics along the depth direction of the subgrade were compared, and the distribution characteristics of the dynamic stress on the surface of the subgrade along the longitudinal direction of the line were analyzed. The critical dynamic stress and cumulative deformation were used as indicators to evaluate the long-term dynamic stability of the subgrade. Results show that water has a certain effect on the dynamic characteristics of the subgrade, and the dynamic stress and acceleration increase with the water content. With the dowel steel structure set between the rail-bearing beams, stress concentration at the end of the loaded beam can be prevented, and the diffusion distance of the dynamic stress along the longitudinal direction increases. The dynamic stress measured in the subgrade bed range is less than 1/5 of the critical dynamic stress. The postconstruction settlement of the subgrade after similarity ratio conversion is 3.94 mm and 7.72 mm under natural and rainfall conditions, respectively, and both values are less than the 30 mm limit, indicating that the MLS maglev subgrade structure has good long-term dynamic stability.

Development and testing of knife-plate connected steel panel dampers

Steel panel dampers (SPDs), consisting of the inelastic panel and elastic connecting segments, have been widely used in steel building structures commonly with brace- or stub-column-type configurations, especially in high seismic regions. The elastic connecting segments of stub-column-type SPDs were usually significantly enlarged to ensure their elasticity under the associated extreme loads of the inelastic panel. With the aim of improving the structural efficiency and ductility capability of SPDs, a novel design, named as knife-plate-connected SPD (KSPD), was proposed in the study. The proposed KSPD consisted of one steel panel and two boundary-columns on the horizontal sides with pinned column ends, which were achieved by knife-plate details, connecting to the framing systems. The designed configuration of KSPDs potentially reduced the aspect ratio of the steel panels for easily achieving shear yielding while remaining the stud-column appearance, and mitigated the deformation amplification of the steel panels usually occurred in conventional stub-column-type SPDs. Five full-scale KSPD specimens with various configurations of the panel stiffeners have been experimentally examined and compared under cyclic loadings including fatigue cycles. The feasibility of the KSPD design was experimentally validated, and the developed KSPDs were verified to achieve stable energy dissipation and significant ductility of approximate ten and cumulative plastic deformation (CPD) value up to 796. For the design purpose of the members, the width-to-thickness limits of the steel panel were established to prevent panel buckling and the sub-panel edge fracture upon the test results, respectively, and a design inequality of the knife plates upon strengths was developed to prevent the fracture of the knife plate. Finally, the design suggestions of the proposed KSPD were summarized upon the experimental results and findings of the study.

Microstructure, properties and deformation mechanism of HCCM horizontal continuous casting Cu–Ni–Co–Si alloy strip during cold rolling

Cu-1.3 wt%Ni-1.0 wt%Co-0.9 wt%Si-0.1 wt%Mg alloy strip with 10 mm in thickness produced by heating-cooling combined mold (HCCM) horizontal continuous casting was cold rolled. Microstructure evolution and mechanical properties of the cold-rolled alloy strips with different reduction were studied, and the deformation mechanism was clarified. The results showed that the continuous casting strips had axial columnar grain with main <001> orientations and straight small angle grain boundaries, the elongation after fracture was up to 25.0%, which can be directly processed by large deformation cold rolling, and the maximum cumulative cold deformation was up to 99%.When the reduction was 40% and 60%, the dislocation bands crossed each other and shear bands formed, and the alternating distribution of soft/hard oriented grains were conducive to improve the deformation coordination ability of micro-region under high strain. When the deformation exceeded 80%, deformation twins formed and the twins had strong interaction with the shear band and grain boundaries, resulting in strong shear and rotation of the local grains. The tensile strength and hardness increased from 464 MPa to 137HV of the as-cast strip to 629 MPa and 208HV with reduction 90%, respectively, while the elongation decreased from 25.0% to 4.1%. These results can lay a foundation for the development of compact method for producing high performance Cu–Ni–Co–Si alloy strips.

Integrated Approaches for Field Mapping by Traditional Investigation and Satellite PSInSAR Data: Results from the Montemartano Landslide (Central Italy)

The study presents an integrated investigation of a complex landslide based on multitemporal stereo aerial photographic interpretations, existing geotechnical monitoring data, and different PSInSAR datasets. The available information allowed for the quantification of the deformation history, also in periods with no monitoring in the field, making it possible to revise the geometry of the landslide compared to the official landslide mapping. Data from sparse inclinometers are compared with more spatially continuous satellite measurements, showing that the two monitoring techniques are consistent in terms of cumulative deformation trend and in terms of response to prolonged drought and wet periods. Therefore, reliable landslide mass displacements can be monitored using satellite products when ground instrumentations are no longer operating. Understanding the landslide behavior to rainfall conditions offers an important insight into the velocities and cumulative displacements expected during similar stages of enhanced landslide activity. The findings can be helpful to support urban planners in re-evaluating hazard and risk classification and implementing efficient mitigation techniques to reduce landslide damage.

Cumulative cyclic response of offshore monopile in sands

Satisfactory performance of offshore wind turbines is governed by the cyclic response of its foundation under wind and wave. Most methods of evaluating the lateral cumulative deformation of monopile due to cyclic loading are based on small-diameter pile tests installed in dry sand. This paper investigates the cumulative deformation of large-diameter monopiles installed in saturated sand. A numerical model was developed employing FLAC3D and was validated by comparing its predictions with the results of triaxial tests and centrifuge tests. The validated numerical model was used to evaluate and compare the cyclic responses of monopiles between saturated case and no pore pressure case. To evaluate the cumulative deformation for offshore monopile due to cyclic loading, the numerical model was refined to account for the effects of number and amplitude and frequency of cyclic loading, soil permeability coefficient, soil relative density and pile diameter. It was found that the larger subsidence and the less capacity of soil around the pile is caused by accumulation and dissipation of transient excess pore pressure, thus the monopile in saturated sand would experience the larger cumulative deformation. Correspondingly, based on this parametric study, an analytical model was developed to calculate the pile-top cumulative displacement of offshore large-diameter monopile under lateral cyclic loading considering the effects of pile diameter. This analytical model was validated against the results of centrifuge tests and model pile tests in saturated sands.

Large-size shape memory alloy plates subjected to cyclic tension: Towards novel self-centring connections in steel frames

In this study, the hysteretic behaviour of shape memory alloy (SMA) plates under cyclic tension-release loadings was examined to promote their seismic applications, with an emphasis on large-size SMA plates with different geometries. Based on a series of SMA plate coupons extracted from base plates with different geometries, the thermal characteristics were investigated, and the phase transformation behaviour of the SMA plates was characterised. Subsequently, cyclic tension-release tests were conducted on the SMA plates in the laboratory, and the key mechanical performance indexes including the transformation strength, post-yield behaviour, self-centring capabilities, and energy dissipation abilities were carefully investigated. According to the results, SMA plates have a comparatively encouraging self-centring ability and moderate energy dissipation capabilities within a specified strain range. However, larger SMA plates show less satisfactory self-centring behaviour and are prone to brittle fracture at the edges. Based on the test programme, a numerical investigation was conducted to offer further insight into the potential applications of large-size SMA plates in the seismic field. A practical modelling procedure, namely the hybrid finite element (FE) modelling technique, was proposed and used to reproduce the degradation and cumulative residual deformation in the SMA plates. Moreover, nonlinear response history analyses (NL-RHAs) were performed on a prototype steel frame equipped with SMA plates in the connections to verify the feasibility of using large-size SMA plates in steel structures.

Research on a double frame hydraulic press with PTS using winding steel wires

The desired preloading effect of a hydraulic press frame parts (upper/lower semi-circular beams and columns) with Pre-Tightening Stress (PTS) by means of Winding Steel Wires (WSW), which is directly related to the reliability and normal safe operation of the hydraulic press. The deformation of the Hydraulic Press Column (HPC) is an important indicator of the optimal preloading effect of the hydraulic press. As a technical bottleneck, the continuous cumulative deformation of a HPC under seven time-varying steps is critical issues especially in theoretically calculated for a 20 MN double-frame hydraulic press with PTS using WAW. A solid model with a PTS frame is pre-designed by 3D software, and two simulation methods, equivalent pressure loading and equivalent temperature loading, are used to simulate and analyze the continuous cumulative deformation of the HPC under each step in Ansys Workbench software. By comparing the deformation and error analysis in the three cases above, the feasibility of the two simulation methods is verified, which leads to the advantages and disadvantages of each method in order to guide the subsequent design.

Effect of rolling deformation on microstructure and mechanical properties of Mg–Y–Nd–Al alloy

In this paper, a low-cost and high-performance Mg–4Y–3Nd–1.5Al rolled magnesium rare earth alloy sheet was developed by a multi-pass rolling process. The effect of cumulative rolling deformation on the microstructure and mechanical properties of the alloy sheet was studied. It is found that with the increase of rolling passes, the proportion of dynamic recrystallisation grains increases, the grains are refined and the texture strength is weakened due to the combined effect of particle excitation nucleation mechanism and grain-boundary-induced nucleation mechanism. The results show that fine-grain strengthening and work hardening are the main reasons for the high strength of the alloy sheet. This experiment provides scientific guidance for developing fine-grained magnesium alloy sheets.

Monitoring Land Subsidence along the Subways in Shanghai on the Basis of Time-Series InSAR

In recent years, Shanghai has entered a stage of microscale land subsidence, but the uneven subsidence is still significant, with long-term impacts on the operational safety of subways and other infrastructures. On the basis of 154 high-resolution Terra Synthetic Aperture Radar-X (TerraSAR-X) images captured from 2013 to 2020 and the time-series persistent scatterer-interferometric SAR (PS-InSAR) method, the land subsidence along the subways in Shanghai was acquired, and the levelling data of 56 benchmarks were used to validate the measurements derived by PS-InSAR. The results indicated that the two data sets agreed well, with a correlation coefficient of 0.9 and maximum D-value of 4.0 mm derived from six pairs of comparative data sequences. The proportion of PS points showing deformation rates between −3.0 mm/a and 3.0 mm/a reached 99.4%. These results indicated that the land subsidence trend along the subway was relatively stable overall, while significant deformation was distributed mainly along the suburban subways, especially the lines that were newly open to traffic, such as Line 5 and the Pujiang line (PJ Line); along these lines, the proportions of PS points with deformation rates exceeding ±3 mm/a were 7.2% and 7.6%, respectively, and the proportions were much smaller in the other lines. The maximum cumulative deformation (MCD) along the subways was located between Jiangchuan Road Station and Xidu Station of Line 5 with a value of −66.4 mm, while the second and third MCDs were −48.2 mm along Line 16 and −44.5 mm along PJ Line, respectively. Engineering constructions, such as human-induced ground loads, foundation pit constructions, and road constructions, were the main factors affecting local land subsidence. The analysis results also showed that land subsidence was relatively significant during the period before the subways were open to traffic due to subway construction, while land subsidence clearly slowed after the subway lines were open to traffic. This deceleration in land subsidence was closely related to the rise in the groundwater level.

Lateral deformation of expressway embankment on the Qinghai–Tibet Plateau: field observation and theoretical model

ABSTRACT This study discusses a two-year-long field observation of the lateral deformation and ground temperature of an experimental expressway embankment on the Qinghai-Tibet Plateau. The distribution features and evolution process of lateral deformation were obtained and analysed. The results showed that the maximum lateral deformation over 2 years was higher than 14 mm and continues to increase. Large lateral deformations occur only at two depths and can be disregarded at other depths. In layers with large lateral deformation, the cumulative lateral deformation grows periodically during the thawing period and decreases during the freezing period. The distribution and evolution features of the monitored lateral deformation indicated that it was caused by thermal stress, and the lateral deformation may be identified as creep–springback deformation under variable thermal stress conditions. Finally, a creep model under a periodic thermal load was established to verify the effectiveness of the proposed lateral deformation mechanism in explaining the lateral deformation behaviour of embankments. The calculations showed that the proposed mechanism can explain the crucial features and accumulation of lateral deformation. The results and analyses reported in this study can provide new references for research on road deformation and disease development.

Experimental investigation on dynamic characteristics of fiber-binder modified subgrade filler after freezing-thawing under cyclic loading

To examine the dynamic stability of fiber-binder modified subgrade filler (MSF), the dynamic triaxial test of MSF is carried out under the long-term cyclic loading after the freeze–thaw cycle. This paper describes the relationship between cumulative plastic strain (CPS) and the number of loading cycles (NLC) changing with different fiber contents, fiber lengths, additions of binder material, and freeze–thaw cycles. The critical dynamic stress under various influencing factors is determined by the numerical fitting method, and the critical dynamic stress model of MSF with multi-factor change is established. Then the normalized dynamic strength mechanical model is proposed by analyzing the normalized characteristics of dynamic strength concerning static strength. It is found that the MSF is brittle failure, the relationship between CPS and loading cycles before failure is roughly linear, and the shape of the curve after failure is approximately exponential. Compared with unmodified subgrade filler, the CPS resistance of MSF is significantly improved. The dynamic stress level required for the failure of MSF increases with fiber length and the addition of binder material increasing, and there is an optimum fiber length of 12 mm corresponding to the maximum cumulative deformation resistance. The improvement measures could improve the freeze–thaw resistance of the subgrade filler. After three and nine freeze–thaw cycles, the dynamic stress intensity of the MSF increased by 1.9 and 2.4 times compared with the unmodified filler. The proposed critical dynamic stress mechanical model of MSF provides an effective method and reference basis for controlling the long-term cumulative deformation of the railway subgrade in seasonally frozen soil regions. The normalized strength model of failure strength for MSF varying with the NLC is helpful to quickly judge the dynamic stress level required for the subgrade failure within a given number of train loads.

Critical Dynamic Stress and Cumulative Plastic Deformation of Calcareous Sand Filler Based on Shakedown Theory

Calcareous sand is a special marine soil rich in calcium carbonate minerals, characterized by brittle particles. It is, therefore, widely used as a filling material in the construction of islands and reefs. In this study, a series of cyclic tri-axial tests were conducted on calcareous sand taken from a reef in the South China Sea under different confining pressures and cyclic stress ratio (CSR). Then, applying the shakedown theory, the cumulative deformation of calcareous sand under a long-term cyclic load of aircraft was evaluated. Results showed that with the increase in the effective confining pressure, the stress–strain curves of calcareous sand showed a change from the strain-softening to the strain-hardening state; the volumetric strain of calcareous sand showed a change from shear shrinkage and then shear expansion to continuous shear shrinkage. Calcareous sand showed three different response behaviors under cyclic load: plastic shakedown, plastic creep and incremental plastic failure. With the plastic strain rate as the defining index, this study determined the critical CSR of calcareous sand under different shakedown response statuses and found them to increase with the effective confining pressure. The empirical formula for critical stress was established based on the fitting analysis of critical CSR under different confining pressures, taking the confining pressure as the variable. At the early stage of the cyclic load, calcareous sand samples were under compression. When the resilient modulus grew rapidly and the number of loading cycles continued to increase, the particles of calcareous sand samples were crushed, causing the fine particles to fill the voids among coarse particles, further compacting the samples and increasing the resilient modulus of calcareous sand samples. Hardin’s breakage potential model was adopted to quantitatively describe the particle breakage of calcareous sand samples before and after tests. The results indicated that calcareous sand samples produced obvious particle breakage when the CSR was small. As the CSR increased, the extent of the breakage of the sample particles first increased and thereafter stabilized. This study provides a theoretical reference for the assessment of the dynamic stability of calcareous sand subgrade subjected to traffic loads.

Research on the deformation control of surrounding rock about large-section tunnel in strong-medium weathered slate

Affected by dip angle and thickness of strata and the tunneling method, soft rock tunnel has obvious characteristics of large deformation, long deformation time and difficult support. Based on a case study of Gelong the deformation and failure mechanism of surrounding rock, stress characteristics of supporting structural and control method of large section highway tunnel passing through strong-medium weathered carbonaceous slate stratum are studied. This paper proposed construction method based on strengthening the longitudinal stiffness of supporting structure and increasing the integrity of surrounding rock, The results showed that the deformation of surrounding rock and the stress of supporting structure increased rapidly in the early stage of construction. The cumulative deformation of vault settlement and horizontal convergence reached 116.9 mm and 97.9 mm, respectively, accounting for 73.53% and 76.62% of the total deformation. The proportion of surrounding rock pressure shared by the primary support and the secondary lining was about 8.9:1.1. This shows that the initial support after comprehensive reinforcement has a strong supporting capacity, and effectively reduces the secondary lining pressure of the tunnel, which plays a vital role in the long-term service of the secondary lining.

Numerical calculation of a 20MN heavy duty hydraulic press for analyzing the double frame pre-stressed steel wire winding

The expected preloading effect of a hydraulic press frame parts (upper/lower semi-circular beams and columns) with pre-stressed by means of Winding Steel Wires which is directly related to the reliability and normal safe operation of the hydraulic press. The deformation of the Hydraulic Press Column (HPC) is an important indicator of the optimal preloading effect of the hydraulic press. A novelty of this project is to break through a bottleneck technology, the continuous cumulative deformation of a Hydraulic Press Column under seven time-varying steps is critical issues especially in theoretically calculated for a 20 MN double-frame hydraulic press with pre-stressed using WAW. A solid model with a pre-stressed frame is pre-designed by 3D software, and two simulation methods, equivalent pressure loading and equivalent temperature loading, are used to simulate and analyze the continuous cumulative deformation of the HPC under each step in Ansys Workbench software. By comparing the deformation and error analysis in the three cases above, the feasibility of the two simulation methods is verified, which leads to the advantages and disadvantages of each method in order to guide the subsequent design.

MT-InSAR Unveils Dynamic Permafrost Disturbances in Hoh Xil (Kekexili) on the Tibetan Plateau Hinterland

Hoh Xil is an uninhabited extremity secluded on the Tibetan Plateau hinterland. A complete mapping of ground motion variation in Hoh Xil is essential for in-depth understanding of terrain’s responses to climate change on the Tibetan Plateau. However, the inaccessibility and extremely harsh environment impeded extensive field investigations on landform alteration and its formative process. Such difficulty can be resolved by Interferometric Synthetic Aperture Radar (InSAR), which enables a broad detection of subtle permafrost motions at millimeter precision. This study, for the first time, accomplished a Multi-temporal InSAR (MT-InSAR) deformation mapping from 2015 to 2020 in Hoh Xil, with a wide coverage of about 200,000 km <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . 1,592 Sentinel-1 images were processed based on the small baseline subset (SBAS) technique. The results show that Hoh Xil was experiencing dynamic permafrost disturbances. Thawing permafrost with both the linear subsidence rate higher than 2 mm/yr and the periodic amplitude over 2 mm was primarily detected in areas of flat or gentle slopes. The InSAR cumulative deformation is highly correlated with permafrost thawing depth. Significant lag times were identified between seasonal oscillation of InSAR deformation and land surface temperature (LST). Thermokarst landforms of retrogressive thaw slumps and thermokarst lakes broadly formed and dynamically evolved as a consequence of permafrost degradation. Particularly, widespread thawing permafrost characterized by the spatial clustering of thermokarst lakes appeared to occur in areas adjacent to large lakes. The discovered dynamic permafrost disturbances in Hoh Xil manifested even the secluded Tibetan Plateau hinterland was facing the threat of climate change.