Delay compensation method plays an important role in maintaining the stability and accuracy of the real‐time hybrid simulation (RTHS). Inverse compensation (IC) method establishes a first‐order discrete transfer function model to represent servo‐hydraulic dynamics and provides an easy‐to‐implement compensation for RTHS. Only one parameter is required for the IC method, and it can be adjusted through

Although statistical models are efficient in most cases to analyze concrete dam displacements, these models are built on several hypotheses, leading to uncertainties especially for special periods. The special statistical models, improving estimations of the non‐stationary thermal and the non‐monotonic time‐dependent effects, are proposed for the displacements of high arch dams during their initial

Long‐term performance of existing bridge structures provides stakeholders with information that facilitates decision making for reasonable and optimal maintenance and management. The neutral axis (NA) is a potentially reliable and robust indicator to evaluate bridge performance since it depends on the loss of elastic modulus or effective sectional area. In this study, the NA indicator is defined and

The application of the acoustic emission (AE) and damage theory to the evaluation of coal rock stability requires a clear comprehension of the influence of joints. The mechanical and AE response characteristics and damage evolution characteristics of samples with different joint angles were analysed through uniaxial compression tests. The results show that the angle between the loading principal stress

Considering that dam deformation and its influencing factors present complex nonlinearities, a modified deformation monitoring model is proposed in this study. On the basis of the systematic analysis of the effects of environmental influencing factors on dam deformation, this study attempts to explore the functional relation between dam deformation and sediment deposition based on the theory of classical

The accurate and stable identification of the traffic load distribution on the bridge deck is of great significance to bridge health monitoring and safety early warning. To accomplish this task, we have combined the weigh‐in‐motion system (WIMs) with machine vision and developed a traffic load monitoring (TLM) technology for the whole bridge deck. For bridge health monitoring, the TLM should be available

Time‐frequency analysis of structural vibration responses provides essential information for structural system identification, modal updating, and condition assessment. However, spurious peaks introduced by the strong noise will significantly increase the false positive rate as well as compromise the sparse time‐frequency signal representation. This paper proposes a high‐resolution time‐frequency representation

In this article, a novel algorithm is proposed for real‐time system identification using hierarchical interhealing model classes. One major difficulty in the system identification for large structures is to determine the complexity of the structural model and the number of unknown parameters. One can detect finer damages with more unknown stiffness parameters, but this may cause fluctuating or even

Damage, be it a material or a geometric degradation, modifies some features of the response foreseen by the original structural design. These variations, once the dependence on the damage causing them is established, can be used for identification purposes. In the literature, vibration‐based approaches usually compare some responses of linear elastic structures with dissipative properties that are

Mode shapes have been playing a vital role in the research and application of bridge structural health monitoring. This paper presents a novel indirect method identifying bridge mode shapes using dynamic responses of a tractor–trailer vehicle model, which consists of one tractor and three instrumented trailers. In an effort to eliminate the road roughness effect, accelerations of adjacent trailers

No abstract is available for this article.

Structural health monitoring (SHM) has been developed and applied to bridge structures since the early 1980s. Numerous approaches and techniques have been proposed and applied to supertall structures during the recent decade. This paper reviews the SHM techniques and applications in supertall structures. The vibration analysis techniques, seismic effect monitoring, wind effect monitoring, comfort assessment

This paper proposes a practical solution to control a problem of a class of continuum mechanics systems in which spatial equations corresponding to vibrational motions are not resolvable through conventional analytical approaches. Control scheme is constructed based on discrete sliding mode technique regarding a rigid model of a system such that control inputs are selected between Lyapunov stability

Particle tuned mass dampers (PTMDs) have attracted recent attention for reducing seismic demands on large structures. Yet, research on the control performance of PTMDs for soil–structure interaction (SSI) systems under earthquake excitations is non‐existent. This paper presents a comprehensive investigation on the effectiveness of PTMD devices for pile‐supported multistory frames through shaking table

The problem of decentralized semi‐active stabilization of vibration of a beam structure is studied. The decentralized controller's architecture is attained by means of optimal system modelling. In this approach, based on a specially designed and optimized set of basis functions, the solution to the continuous Euler–Bernoulli beam equation is approximated by a discrete system, where the mass and stiffness

In this paper, a hierarchical outlier detection approach is proposed for online distributed structural identification. In contrast to centralized identification, distributed identification extracts important features from the raw response data at the sensor nodes and transmits only them to the base station. Therefore, outlier detection is substantially more complicated than the traditional approach

While conventional seismic isolation bearings are usually inefficient for bridges with tall piers, rocking foundation is a promising approach mitigating their seismic demands and improving post‐earthquake resilience. However, excessive tilt angle might occur at rocking interface and lead to overturning during strong earthquake excitations. This paper investigates the efficiency of various energy dissipation

Past earthquakes have shown that traditional structural design relies on the component ductility to dissipate the earthquake energy. This has led to significant damage for the structure. Innovative energy dissipation devices have been developed in the past to dissipate the earthquake energy. However, the big disadvantage of traditional energy dissipation devices is the lack of self‐centering capabilities

Prestressed concrete beams are widely used in structures and infrastructures for their superior control effects on cross‐sectional area, cracking, and deformation. However, the fire resistance of ordinary prestressed beams is unsatisfactory due to the serious material degradation of concrete and steel, as well as the prestress loss at elevated temperatures. To achieve an acceptable fire resistance

This study introduces simple piecewise linearisation in time series (SPLiTS), for time‐domain inversion (TDI) to estimate the physical parameters of nonlinear structures. SPLiTS considers a nonlinear structure to be a set of piecewise linearised structures based on each half‐cycle wave in the displacement response data. For the linearisation, SPLiTS intentionally minimises the effect of the central

In this paper, a sensitivity‐based finite element (FE) model updating method using singular value decomposition (SVD) of frequency response function (FRF) is introduced. An exact sensitivity equation is proposed by incorporating measured responses of a damaged structure in the mathematical formulations. A set of incompletely measured natural frequencies of a damaged structure and mode shapes of the

No abstract is available for this article.

Bayesian optimal sensor placement, in its full generality, seeks to maximize the mutual information between uncertain model parameters and the predicted data to be collected from the sensors for the purpose of performing Bayesian inference. Equivalently, the expected information entropy of the posterior of the model parameters is minimized over all possible sensor configurations for a given sensor

Nonlinear mapping of the fuzzy relation exists between structural inputs and outputs, as well as between structural global and local response. It is difficult for the numerical simulation to introduce the nonlinear effects of the variability of loading effects and the uneven deterioration of structure. The big monitoring data make it feasible to mine these nonlinear effects, and the network of deep

Fire accidents in the concrete structures affect the safety of human beings and structural components. Due to higher temperatures, thermal cracks are conceived in concrete elements. Crack identification, localization, and quantification are the three major components in the damage assessment system. This paper aims to detect thermal cracks of fire‐affected concrete structures using ripplet transform‐based

In this study, the bridge concrete structure is taken as the research object, and the real image is used for crack identification. In structural engineering, surface cracks are the main indexes of durability and service performance of structures. Artificial visual inspection is often considered ineffective in terms of cost, safety, evaluation accuracy, and reliability. In this article, a simple, high‐classification

Many existing structures suffer from damage due to age or accumulated damage from hazards. It is important to accurately assess the present conditions of these aging, deteriorating, and damaged structures. In recent years, laser scanners have been increasingly used for capturing the in situ conditions of structures. They are used for collecting dense and high‐resolution point clouds of scenes for structural

This paper presents an innovative gear‐driven rotation‐amplified rubber viscoelastic damper (GRRVD) to reduce the seismic shift responses of beam‐column connections in frame structures. Based on the principle of gear transmission, the damper can amplify the rotational deformation of the beam‐column joints of frame structures according to actual engineering needs and give full play to the energy dissipation

This paper presents a comparative study about the numerical and experimental system identification and model updating‐based automated damage detection of concrete‐encased composite column‐beam connections. Four different column‐beam connection types named as CBC#A, CBC#B, CBC#C, and CBC#D were considered without any changes in geometrical configuration. Numerical and experimental dynamic characteristics

The detection of wheelset bearing faults is of extreme importance for railway vehicle operation safety. Wheelset bearing faults induce impulses in vibration signals, which are hard to detect because of signal modulation and environmental noise. To suppress noise and identify these impulses effectively, we propose a method that leverages morphological signal and image processing techniques. The proposed

This paper investigates the effects of uncertainties and modeling errors on the performance of nonlinear updating process through an experimental study on two 1/8‐scale four‐story steel moment‐resisting frames. To examine the accuracyo of the models calibrated using different data features and modeling assumptions, the actual structural responses obtained from shaking table tests and the response of

This paper presents a solution to the multi‐site structural damage identification problem using a data‐driven method and constrained independent component analysis (cICA). While existing studies in this field presented encouraging results for single‐site damage identification, limited research effort has been devoted to identifying multi‐site damage due its complexity. Efficient features for single‐site

Modal parameter variation plays an important role in bridge health monitoring. But tracking the long‐term variation of modal parameters is restricted by the modal identifiability. Since some modes cannot be identified due to the limitations of sensor locations or excitation conditions, the identified modes will be missing or misclassification in the tracking process. In this paper, the multistage tracking

Bridge stay cables are susceptible to dynamic excitations due to their low intrinsic damping and lateral stiffness. Installation of transverse passive dampers near the cable‐deck anchorage on a rigid/flexible support is one of the practical measures to mitigate cable vibrations. The limited performance of conventional positive stiffness dampers (PSDs) has led to the emergence of negative stiffness

A comprehensive study has been carried out on the seismic behavior of straight‐tenon joints (STJs) reinforced with the state‐to‐art friction damper. Quasi‐static cyclic tests were conducted on three reinforced test specimens and one contrast joint, and friction coefficients were selected as the variables. The failure modes and the cyclic behaviors of both STJs and fiction plates were obtained. Numerical

Real‐time dynamic hybrid testing (RTDHT) is a state‐of‐the‐art experimental technique for evaluating the performance of a structural system subjected to time‐varying loads. Because of the superiority of shaking table for testing rate‐dependent and inertial effect existing in structural system, shaking table‐based RTDHT is an important branch in RTDHT family, in which shaking table is used to impose

Application of recycled coarse aggregate concrete (RAC) will generate considerable environmental benefits. However, the properties of RAC must be studied before being adopted in structures. In this research, the failure process and damage assessment of RAC under compression were investigated by applying acoustic emission (AE) technology. The variables include loading rates, maximum coarse aggregate

Masonry heritage structures are often affected by slow irreversible deterioration mechanisms that can jeopardise structural stability in the foreseeable future. Static structural health monitoring (SHM), aimed at the continuous measurement of key slow‐varying parameters, has the potential to identify such mechanisms at a very early stage. This can greatly facilitate the implementation of adequate preventive

An inerter‐based quasi‐zero stiffness (IQZS) vibration isolator is proposed to further enhance the dynamic performance of the QZS one. It combines the superior nonlinear stiffness characteristic of the QZS vibration isolator and the beneficial mass magnification effect of the inerter. The diamond‐shaped structure is used as the negative stiffness structure; an additional spring is added together with

In recent years, several studies proposed new techniques aimed at improving the performances of rigid block‐like objects under base excitation. The majority of these studies considered passive control methods, such as base isolation or other techniques based on the tuned mass damper principle. Only few studies considered active and semi‐active control methods applied to the dynamics of rigid blocks

Over the last two decades, vibration‐based structural health and condition monitoring has gradually become one of the main methods for monitoring changes in a structure on a global scale. This method has been applied to damage detection in many areas, including aerospace, mechanical and structural systems. However, it has not been widely used for identifying condition change of the structure itself

In this paper, experimental data from tests of a helical fluid inerter are used to model the observed hysteretic behavior. The novel idea is to test the feasibility of employing mem‐models, which are time‐invariant herein, to capture the observed phenomena by using physically meaningful state variables. First, we use a Masing model concept, identified with a multilayer feedforward neural network to

Bridge infrastructure assets possess ultimate value for safe, resilient, and sustainable transportation networks. Monitoring of bridge structural characteristics is an essential process to minimize damage‐associated risk but requires expensive sensor instrumentation, manpower, and expert intervention. Besides, certain bridges' vitality exceeds practical needs due to their landmark identity with symbolic

No abstract is available for this article.

In this study, the robust optimum design of a recently developed passive control device, i.e., tuned mass damper inerter (TMDI) is investigated to control a 10‐story base‐excited shear building benchmark. The H2 and H∞ of three different objective functions (i.e., minimizing roof displacement, minimizing 7th‐story displacement, and maximizing the TMD stroke) are selected as objective functions for

The installation of a damping bracing system is regarded as an effective means to upgrade the seismic capacity of steel moment‐resisting frames (MRFs), a common structural form for buildings. However, conventional damping braces are incapable of eliminating residual deformation demand. Shape memory alloy (SMA) braces present an emerging seismic upgrading solution to this problem. However, the corresponding

Output‐only identification of civil structures is a challenging yet in escapable task, as input excitations are unmeasurable in many real‐world situations. This paper presents a new output‐only technique to jointly identify the model parameters of adjacent buildings from their recorded seismic responses. Classic output‐only identification techniques are based on various limiting assumptions about the

This paper demonstrates the potential to use measured deflection responses of a bridge to random traffic as a means of monitoring its structural health. Three displacement transducers are simulated on the bridge at different locations, providing absolute deflection data. The stiffness profile through the length of the bridge is calculated using these data. Vehicle axle loads are calculated as well

The mathematical monitoring model‐based interpretation of recorded quantities, especially of displacements, is essential for the structural health diagnosis of concrete dams. In practice, dam displacements are frequently interpreted and predicted by the hydraulic, seasonal, and time model, which considers the thermal deformation effect of a dam body by the periodic harmonic factor. The main purpose

In this paper, damage indicators are presented for bridges based on measured data collected under uncontrolled traffic conditions. The test bridge considered is a small stiff concrete culvert with low dynamics, making it suboptimal for monitoring with accelerometers. Largely static strain responses are measured, with the variability in the vehicle weights and configurations addressed by handling the

Crack detection is an important issue in the health monitoring and performance evaluation of concrete structures. Based on the heat transfer theory, a temperature tracer method and a monitoring system for crack detection in underwater concrete structures are presented in this paper. The system is composed of an integrated sensing and heating system, a monitoring tube, and multiple casing tubes. The

Dampers with negative stiffness behavior have been widely investigated for structural vibration control due to their superior performance. In practical applications, a support in series with these dampers might have some flexibility, that is, the stiffness is positive but finite. This paper investigates the effects of that flexibility on the performance of a passive negative stiffness damper (PNSD)

Visual inspections is a common approach for the network‐scale monitoring of bridges. One of the main challenges when interpreting visual inspections is the observations being subjective and thus the observation uncertainty varies among different inspectors. In addition, observations uncertainties can be dependent on the structural element condition. These two factors introduce difficulties in differentiating

This paper presents a novel and accurate model‐reference health monitoring system for the location of damage to building structures using the dissipated energy approach, frequency domain convolutional neural networks (CNNs), and principal component analysis (PCA). Due to the fact that the earthquake introduces several stress cycles in different directions in the structure, load–strain curves can be

This paper presents a technique for vibration‐based damage detection and localization in engineering structures based on the high‐speed three‐dimensional Digital Image Correlation (HS 3D‐DIC) and local modal filtration. The efficacy of the proposed procedure is demonstrated on a frame structure with different severities of localized damage. The full‐field vibration data acquired under the white noise

The paper introduces a procedure to automatically identify key vehicle characteristics from vibrations data collected on a suspension bridge. The primary goal is to apply a model of the dynamic displacement response of a long‐span suspension bridge to traffic loading, suitable for automatic identification of the vehicle passage over the bridge. The second goal is to improve the estimation of the structural

This paper proposes a bolt looseness detection method based on the ultrasonic wavefield energy in the Lamb wave reflected from a target bolt. The full wavefield inside the area of the specimen containing the target bolt was first visualized. The ultrasonic wave propagation imaging (UWPI) approach was used for visualizing the interaction of the wavefield with the elements on the specimen such as the

To assess the current conditions of bridges in practice, a manual visual inspection is commonly used for maintenance purposes. Because manual visual inspection is time consuming, expensive, and laborious, computer vision with deep learning techniques has recently been introduced as a promising tool for automatic damage detection and classification. However, damage localization is difficult in that