Crack Location Research Articles

Analysis of dynamic features on local fatigue cracks in steel bridges

In steel bridges with orthotropic decks, a common and important engineering structure, fatigue cracks can appear under long-term operation. Existing artificial detection is the main approach to detecting fatigue cracks in steel bridges, in addition to some non-destructive testing or image processing methods, and unmanned aerial vehicle are applied to improve accuracy and efficiency. However, the detection of fatigue cracks in steel bridges based on the variation of dynamic responses or dynamic parameters is another attractive idea, which is still rarely mentioned and investigated in the international literature. The reason is that local cracks usually have negligible effect on the global dynamic characteristics of steel bridges, resulting in the insensitivity to dynamic indexes to fatigue cracks. On this occasion, this study numerically explores and establishes two sensitive damage features to local damage, i.e., the crack in the vertical rib, based on the fatigue cracks found on the Türr Istvan bridge over the Danube River in Hungary. The local vibrations of the bridge are excited through the local impact on the structural details, i.e., the vertical rib, and then the high-order frequencies of the entire bridge are examined. The obtained high-order frequencies are proved to be more sensitive to the fatigue cracks on vertical ribs and increased with the crack depths. On the other hand, the correlation of the stress curves on opposite sides of the crack is sensitive to the depth of the crack. If fatigue cracks are found, the development degree of the fatigue cracks can be monitored more accurately by focusing on the correlation of local stresses near the crack. These two damage features are numerically proven to have feasibility and are expected to break through the insensitivity of the existing dynamic detection methods.

Investigation on Cracking Cause of Drill Pipe Joint Used in an Ultra Deep Well

The drill pipe joint cracked during service, resulting in joint failure. The geometric dimensions of thread, chemical composition and microstructure of the drill pipe joint were tested. The geometric dimensions, chemical composition and microstructure were found to comply with the standard requirements. The whole macroscopic fracture didn’t show obvious corrosion product. The tensile properties, Charpy impact properties, and Brinell hardness met the standard requirements. Microstructure of fracture was analyzed, which showed a typical erosion micromorphology with parallel arranged fatigue strips. Through simulation analysis, it was found that the location of cracking was the stress concentration area. The failure mechanism of the drill pipe joint was revealed. The stress concentration led to fatigue cracking at the drill pipe joint. After the fatigue crack penetrated through the wall thickness, the drilling fluid leaked from the inner wall to the outer wall. The flow rate of the leaking drilling fluid is significantly increased. And it is sprayingly leaked, which further leads to fan-shaped erosion damage of the cracked surface from the inner wall to the outer wall.

Método DIC aplicado na calibração de um modelo MEF de interface coesiva rocha-argamassa

Abstract In civil engineering, the stability of many structures depends on the physical properties of the contact between the concrete seated on the rocky foundation surface. Usually, they are critical structures of great importance to society, such as: bridges, tunnels and dams. Thus, the shear behavior of rock-concrete joints is a key factor of the structural stability. The method of cohesive zones (CZM) allows to simulate the beginning of the formation of a crack and its propagation, without knowing the crack location or when it will start. Thus, in this work, a numerical model was developed capable of simulating the failure due to interfacial delamination of the contact between a structure formed by mortar seated on a rocky granite leaning surface. The calibration of the numerical model was performed using the experimental test results of simple compression on a block of rock in contact with the mortar by an inclined interface. The test was monitored using a high-resolution digital camera. The data were processed using the digital image correlation method (DIC) to obtain displacement data of the laboratory test. The DIC results were used to calibrate the nonlinear numerical model of the test using the bilinear method of cohesive zone in the rock-mortar interfacial contact elements. By a parametric analysis varying the maximum shear stress parameter of the contact cohesive elements, the bilinear law was adjusted (Maximum tensile stress and critical displacement and damage rate). Indirectly, the rate of release of energy of critical deformation from the rupture of the contact was also estimated.

Underwater Engineering Crack Identification based on Lightweight Convolutional Neural Network

Convolutional neural network is an effective model for image feature recognition, which is widely used in crack recognition and risk detection. The crack identification of underwater engineering involves a huge scale of data, and the traditional R-CNN model and Faster R-CNN model have the problems of large number of model parameters and low efficiency for crack identification. Therefore, a lightweight convolutional neural network based crack identification method for underwater engineering is proposed to optimize the efficiency and accuracy of crack identification. Deep separable convolution is used to replace the common convolution of YOLOX network (an open source high-performance object detection algorithm), reducing the redundant parameters of the model to achieve lightweight design. Following the backbone feature extraction network framework of YOLOX, Transformer (a structure based on attention mechanism and forward neural network) vision module is adopted to replace the CSP structure (a feature extraction structure) at the end of the backbone network, adding attention mechanism and enhancing key information extraction capability. Make up for the problem of decreasing feature extraction accuracy caused by decreasing parameter number; Finally, the adaptive spatial feature fusion strategy is used instead of the traditional feature pyramid cascade to implement feature fusion and improve the feature extraction ability of small targets. The test results show that the improved YOLOX lightweight convolutional neural network has good prediction ability for underwater engineering cracks, and can accurately select the crack location, with fewer false detection and missed detection cases. Ablation experiments show that this study builds a lightweight convolutional neural network model, which improves the accuracy of the model to identify underwater engineering cracks. The improved lightweight convolutional neural network is suitable for crack identification in underwater engineering and can be widely applied in the field of underwater engineering risk identification.

Smart monitoring of RC T beams strengthened by external bonded FRP

This study aimed to investigate the cracking behaviour of RC beams strengthened by external smart bonded FRP. A smart CFRP consists of two textile fabrics inside which a distributed fibre-optic sensor (DFOS) is inserted. During the test, the sensor measured the mechanical strain distribution of the composite with a millimetric spatial resolution. Simultaneously crack openings along the beams were detected and measured using digital image correlation (DIC). The results of the strengthened beams were analyzed in comparison to the reference beam, and the crack width are compared. Subsequently a smart CFRP was described and implemented in the tested beams and was used to measure the cracks location. The measurement of strain profile allow then to obtain the level of beam damaged during the loading.

Probabilistic inspection planning for fatigue cracks in floating production, storage, and offloading units

Probabilistic inspection planning for fatigue cracks in floating production, storage, and offloading units

О возможности локального измерения трещиностойкости конструкционных сталей с привязкой к структуре

The scale of heterogeneity of the structures of steels and alloys can be rather large both within one sample and within a product. The procedure adopted in practice for determining the integral values of crack resistance characteristics cannot always reflect this circumstance. In this regard, it is necessary to develop methods for assessing the crack resistance of a medium with a heterogeneous structure. In this work, the authors determined the crack resistance of large forgings made of heat-hardenable 38KhN3MFA-Sh steel (0.38%C–Cr–3%Ni–Mo–V) based on the critical crack opening δс and the J-integral. The presence of critical stages in the development of a ductile crack during testing was assessed by acoustic emission measurements. In combination with the obtained methods of digital fractography of 3D images of fractures, this allowed relating the shape and position of the leading edge of each crack jump to the load-displacement diagram. Measuring the crack opening geometry during the test showed the possibility of determining directly the coefficient of crack face rotation when estimating δс. In general, this allowed constructing a map of the distribution of parameter δс values over the thickness of the sample and estimating the scale of the scatter in crack resistance within one sample – up to 30 %. Such a localization of measurements, primarily of the δc parameter, is comparable to the scale of heterogeneity in the morphology of various types of structures, which was assessed based on the measurement of digital images of the dendritic structure, the Bauman sulfur print, non-metallic inclusions on an unetched section, and ferrite-pearlite banding in the microstructure. This makes it possible to link local crack resistance values to various fracture mechanisms and their accompanying structural components.

Investigation of corrosion behavior of Al–TiO2 nanocomposite produced using air plasma spray and accumulative roll bonding method

This work is an attempt to study the Al–TiO2 nanocomposite properties applying accumulative roll bonding process. For this purpose, nano Titania powder was first coated on aluminum foil by air plasma spraying process. The nanocomposite was then fabricated in one, two, three, five, and seven cycles by ARB. To investigate the effect of ARB process cycles on an Al-5% wt. TiO2 nanocomposite, characterization tests including XRD, quantitative XRD analysis by MAUD software, FESEM, EDS, electrochemical impedance, and TAFEL polarization tests were performed on the samples. The results indicate that the crystallite size reduced from 156 to 31 nm and the dislocation density quadrupled in the composite. The results of XRD analysis showed an increase in the dislocation density in the composite when the number of cycles increases. The reduction of crystallite size and increase of the grain boundaries have caused a sudden increase in the dislocation density. As the ARB cycle increases, the local porosity decreases and the local cracks due to the separation of the titanium sprayed droplets disappear in the matrix phase, and the reinforcing phase has more diffusion in the matrix. With the increase of ARB cycles, the percentage of titanium and oxygen elements on the surface was decreasing, but they remained until the last cycle. Among the non-rolled and rolled samples in different cycles, ARBed samples after 1 cycle and 5 cycles had not only the lowest and highest corrosion current densities but also the highest and lowest total resistance (Rt), respectively. This indicates max corrosion resistance due to the decrease in defect and porosity resulting from plasma spray and min corrosion resistance as a result of formation of galvanic cell between Al-matrix and Ti-reinforcing particles, respectively.

Local crack arrestability of hydrogen-related fracture in high-strength martensitic steel

Local crack arrestability of hydrogen-related fracture in high-strength martensitic steel

ANALYSIS OF NATURAL FREQUENCIES FOR EARLY DAMAGE DETECTION IN CFRP SHAFTS USING RSM-BASED FREQUENCY CONTOUR PLOTS

This study explores early damage detection in carbon fiber-reinforced polymer shafts by analyzing natural frequencies. Modern engineering components often face increased flexibility and high stress levels, leading to cracks in rotating parts, which can result in premature failures. To address this issue, modal analysis, specifically natural frequency analysis, is employed to identify deviations caused by cracks. Cracks alter stiffness and mass distribution, leading to shifts in natural frequencies. The study employs finite element models to simulate various crack locations and depths, normalizing them with respect to shaft diameter and length. A cantilever shaft configuration is utilized with refined mesh structures near the transverse crack. The analysis leverages the frequency contour method with response surface methodology to visualize how crack depth and location influence normalized natural frequencies. Results indicate that crack depth has a significant impact on natural frequencies, while crack location has a subtler effect. Combining depth and location produces the most pronounced frequency variations. The corresponding R² values for the normalized first and third natural frequencies are 95.69% and 96.32%, while for the normalized second natural frequency this value is 75.70%. The study also demonstrates the use of frequency contour curves for accurate crack detection, with the 1st and 3rd natural frequencies being reliable indicators.

Analysis and experimental verification of dynamic characteristics of cantilever plate with fatigue crack

Fatigue cracks in aero-engine blades seriously threaten the stability and reliability of the engine. It is very necessary to identify and diagnose the crack state through vibration signals, and predicting its vibration rules through dynamic analysis is the basis of crack identification. At present, the dynamic model of cracked blades with breathing cracks is mainly established by implanting cracks, and there is a lack of relevant experimental validation. To address the above deficiencies, this paper firstly obtains the real extension path of the cracked plate through the fatigue testing machine, and then introduces it into the cantilever plate finite element model. Then the correctness of the proposed model is verified by natural frequency obtained from hammering test and frequency sweeping test. Finally, the effect of different crack parameters such as crack depth, crack location and plate length on the crack vibration characteristics is investigated based on simulations and experiments. The results indicate that (1) the real fatigue crack obtained by tensile test has larger amplitude peaks under excitation frequency compared with wire-cut crack, and it has stronger nonlinearity to better reflect the vibration characteristics; (2) Specimens show obvious nonlinear characteristics that significant amplitude peaks occur at multiples of excitation frequencies in both experiments and simulations; (3) For the cantilever plate containing breathing cracks, the vibration amplitude totally increased by 18.5% with the increase of crack depth, and it decreased by 41.5% throughout as the crack location became further away from the plate root. This study provides a theoretical basis for detection and diagnosis of blade cracks.

Numerical Study for Damage Identification in Beams Using Continuous Wavelet Transformation and Convolution Neural Network

The discovery and identification of damages in engineering structures is very important in the field of engineering maintenance, as it is a great challenge in presenting new methods in measuring vibrations and discovering damages with the development in the field of automation and high accuracy in discovering damages. In this study, natural frequencies and mode shapes of transverse vibration for damage detection in structures are investigated. The study is performed for various crack depth and crack location. And suggested a new technique based on Continuous Wavelet Transform (CWT) and Convolution Neural Network (CNN). The comparison will be done by simulating the oscillations of a cantilever steel beam with and without defect as a numerical case. The proposed new technique proved to outperform classical methods and has achieved a100% accuracy in the identification of defect position for the data studied.

КОНЦЕНТРАЦІЯ ТЕРМОНАПРУЖЕНЬ В ЦЕМЕНТОБЕТОНІ В ОКОЛІ КАПІЛЯРА, ЧАСТКОВО АБО ПОВНІСТЮ ЗАПОВНЕНОГО ВОДОЮ ПІД ЧАС ЇЇ ЗАМЕРЗАННЯ

Abstract. The article presents the results of theoretical modeling of the effects of thermoforce deformation of a cement-concrete medium in the vicinity of a capillary, partially or completely filled with water, at the stages of lowering the temperature of the system to zero degrees Celsius, turning water into ice at zero degrees and the subsequent drop in temperature. Based on the basic principles of the theory of thermoelasticity, differential equations of deformation of the system are constructed, taking into account the incompatibility of the thermomechanical characteristics of its phases and the peculiarities of the behavior of water when the temperature changes, which consists in its fluidity, incompressi-bility, the dependence of the coefficient of thermal expansion on temperature and the increase in volume when turning into ice. Closed-form solutions are constructed for these equations. It was established that in all cases the thermal stress in the cement-concrete medium is concentrated in the vicinity of the capillary wall and decreases inversely proportional to the square of the radial coordinate. At the stage of turning water into ice, they significantly exceed the strength limit of cement concrete and are the main reason for the formation of localized radial cracks that reduce the frost resistance of the cement concrete structure. Keywords: road materials, capillary pores, water freezing, ice expansion, thermal stress.

Finite Element Method Analysis of Potential Shaft Breakage in Truck Wheel Drive Due to Initial Crack

The need for truck transportation in the city of Langsa is increasing. This is because the residents of Langsa use trucks as a means of transporting palm oil from plantations. Engine component failures are often experienced in every mechanical construction, and these failures are marked by the breaking of these engine components. Cracks become one of the potential sources of failure in the machine structure. There is a need to detect cracks in the shaft at an early stage to prevent damage. Therefore, it should be investigated using appropriate techniques at the early stage of crack formation. The purpose of this research is to find the potential source of shaft fracture relative to the initial crack location on the shaft. This research method is carried out by determining the same initial crack dimensions at two different locations. The initial crack locations are determined through a case study of frequent fractures in the fillet spline and fillet flange locations. The calculation results show that the permissible stress of the shaft is 80.7 MPa. The finite element method simulation results show that the maximum shear stress value on the shaft without an initial crack is 65.234 MPa, on the shaft with an initial crack in the fillet spline location is 69.654 MPa, and on the shaft with an initial crack in the fillet flange location is 78.79 MPa. The finite element method simulation results also show that the von Mises shear stress value on the shaft without an initial crack is 113.29 MPa, on the shaft with an initial crack in the fillet spline location is 120.66 MPa, and on the shaft with an initial crack in the fillet flange location is 137.23 MPa. The finite element method simulation results further show that the von Mises shear strain value on the shaft without an initial crack is 0.000567, on the shaft with an initial crack in the fillet spline location is 0.000630, and on the shaft with an initial crack in the fillet flange location is 0.000693. In conclusion, the potential source of failure experienced by the shaft between the two locations of frequent failure is the shaft with an initial crack in the fillet flange location.

Kaji Teoritis Pengaruh Variasi Letak Retak Terhadap Perambatan Retak Dengan Pendekatan Double Cantilever Beam (DCB)

One of the causes of structural failure is the presence of defects in the form of cracks that appear during the manufacturing or usage process of the structure. The propagation of cracks in the structure greatly depends on the value of the energy released rate possessed by the defective structure. Therefore, it is necessary to calculate the energy released rate of a structure that has a crack. One simple approach is the double cantilever beam (DCB) method. The DCB approach is derived from the change in strain energy with respect to the change in crack length. In this study, variations in crack length and crack location will be analyzed using the DCB approach and compared with the Finite Element Method (FEM) approach. It can be concluded that the calculation of strain energy can be performed using the cantilever beam approach, where the results do not significantly differ from the FEM calculations. Additionally, the strain energy is heavily influenced by the length of the beam, as longer beams result in a significant increase in strain energy (cubic relationship). The value of Energy Released Rate (ERR) is highly influenced by the crack length; a longer initial crack length leads to a quadratic increase in the Energy Released Rate (ERR). Furthermore, the value of Energy Released Rate (ERR) is also affected by the crack location; the closer the crack is to the surface of the beam, the higher the Energy Released Rate (ERR) will be.

Electrosynthesis and Performance of Homogeneously Mesoporous Ni-Rich Ni-Pt Thin Films for Efficient Hydrogen Evolution Reaction in Acidic Media

The development of green hydrogen technology requires abundant electrocatalyst materials to (partially) replace costly platinum while maintaining the catalytic efficiency and durability. Nickel is an excellent choice for the partial replacement of Pt for water splitting, and is widely used for electrocatalysis in alkaline media. Although Ni cannot provide an activity identical to Pt, specific nanostructures aimed at a high surface-to-volume ratio, such as nanoporous structures, can significantly improve catalytic efficiency. However, in acidic media, the use of non-noble metals for electrocatalysis requires extensive durability tests to confirm the stability of the alloy. Additionally, the impact of hydrogen itself is often overlooked, as hydrogen is known to cause hydrogen embrittlement in Ni and its alloys.This contribution deals with the synthesis of a homogeneously mesoporous Ni-Pt alloy with high catalytic efficiency (Fig. 1). By electrodeposition from aqueous media, Ni-rich Ni-Pt alloy thin films are synthesised in a wide compositional range (between 60 and 99 at% Ni), depending on the deposition potential. The addition of the amphiphilic block copolymer Pluronic P-123 to the electrolyte formulation enables a micelle-assisted deposition process, resulting in films with homogeneous porosity with an approximate pore size of 10 nm irrespective of composition. Moreover, all thin films are single-phase and nanocrystalline [1], and show excellent performance under hydrogen evolution reaction (HER) in acidic media [2].As determined by Rutherford backscattering (RBS), the as-deposited Ni-Pt thin films with film thickness between 180 nm and 260 nm exhibit Pt enrichment at the surface of 1-2 nm in depth, after which Ni and Pt exhibit constant composition over depth. After hydrogen evolution in 0.5 M H2SO4, a gradient in Ni/Pt ratio over the film thickness is established, indicating preferential leaching of Ni into the electrolyte, and resulting in higher Pt content at the surface. Due to the porosity of the thin films, this leaching affects the entire film thickness. A chronopotentiometric durability test (24 h) reveals that the overpotential stabilises over time, indicating that the leaching of Ni is suppressed once a certain Pt/Ni ratio is attained in the thin films. In addition, the HER electrocatalysis is accompanied by a significant hydrogen uptake, determined by elastic recoil detection analysis (ERDA). Depending on the electrodeposition parameters, the as-deposited thin films already exhibit significant hydrogen concentrations between 2 and 10 at%. After the HER durability test, local cracking is observed by SEM, related to an excess of hydrogen in the thin films. Despite the cracking, no significant detachment of the films from the substrate is observed. The hydrogen contained in the films is assumed to be interstitial and does not affect the metallic nature of the Ni-Pt films. An X-ray photoelectron spectroscopy (XPS) post-analysis shows that the fraction of metallic Ni with respect to Ni in higher oxidation states is higher after exposure to the HER than for the as-prepared surface. Acknowledgement: Financed by the European Union – NextGenerationEU.[1] K. Eiler, J. Fornell, C. Navarro-Senent, E. Pellicer, J. Sort, Nanoscale, 2020, 12, 7749[2] K. Eiler, S. Suriñach, J. Sort, E. Pellicer, Appl. Catal. B, 2020, 265, 118597Figure 1: SEM micrograph of a mesoporous Ni93Pt7 thin film. Figure 1

Evaluating the Corrosivity of Relevant Environments That Can Form on the Surface of Spent Nuclear Fuel Canisters

Austenitic stainless steels (SS), utilized extensively in coastal environments due to their enhanced corrosion resistance, are susceptible to localized corrosion and stress corrosion cracking (SCC) when exposed to chloride environments and sufficient stresses. One potential scenario under which SCC may pose a concern is the storage and eventual transport of spent nuclear fuel (SNF) in SS canisters. The SS canisters are stored in many locations across the United States and may be subjected to corrosion from brines formed by deliquescence of salt aerosols of varying compositions. Recently, the compositions of salts collected from the surface of SNF interim storage canisters at four different storage sites have been evaluated; these represent both coastal and inland sites, and widely differing compositions. The observed salt chemistries vary from laboratory salts commonly used in corrosion testing (i.e., NaCl, MgCl2, and artificial seawater). Herein, we evaluate the relative corrosivity of the brines through polarization scans, exposure tests, and modeling efforts. The results of this study are discussed in terms of potential canister degradation and improved methods to determine the corrosivity of field-relevant environments. SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525. This document is SAND2023-02443C.

Extreme load analysis of flexible wave energy converters utilising nonlocal continuum damage mechanics

In recent years, there has been a notable increase in interest towards Flexible Wave Energy Converters (FlexWECs). These flexible energy harvesters solve structural design challenges faced by rigid-body WECs by responding to external loading by changing shapes. Typically, the structures are made from rubber-like materials which pose few challenges from a material modelling point of view. Firstly, the material is in the finite strain regime requiring a hyperelastic modelling approach, but more critically the material response is expected to change during the operational lifetime. There is softening from both time-dependent viscoelasticity and micro-void growth caused by fatigue loading. The goal of this paper is to understand the latter mechanism and how it manifests within a membrane. To account for this damage accumulation, the gradient-enhanced nonlocal damage model is coupled to a hyperelastic Neo-Hookean constitutive law. The framework has been implemented in the commercial finite element software ABAQUS by exploiting its fully coupled thermo-mechanical formulation. A parametric study is performed on two FlexWEC archetypes: a submerged pressure differential and a floating bulge wave attenuator. The performance evaluation of these devices is carried out by analysing the evolution of the pressure–volume relation and pressure-stretch relation, respectively. The results show that the nonlocal aspects of damage in the pressure differential FlexWECs are small due to membrane action, but the saturation of damage does affect the pressure–volume function of each membrane. However, in the case of attenuator, the damage regularisation plays a crucial role in its behaviour due to the steep stress gradient from the crest of the wave. The outcomes from these analyses suggest FlexWEC design is advantageous from a fatigue loading perspective as it always reaches an equilibrium state which minimises the stress-differential, reducing the likelihood of localised crack growth.

Synthesis of Diels–Alder bond and hydrogen bond synergistic shape memory self‐healing polyurethane elastomers

AbstractSelf‐healing materials exhibit the ability to repair damage and restore their function. Shape memory assisted self‐healing (SMASH) materials are smart materials that automatically close localized microscopic cracks and repair these cracks by bonding damaged surfaces. A novel temperature‐responsive SMASH polymer composite was established by introducing Diels–Alder bonds (D–A) in polyurethane. In this article, dynamic D–A produced by the polymerization of furfurylamine and 4,4’‐bismaleimidodiphenylmethane was introduced into the molecular chain to enable the polyurethane elastomers containing D–A bonds to acquire self‐repairing capability. The self‐healing properties of the synthesized material were examined using polarized light microscopy, which revealed excellent fracture healing. The mechanical properties before and after healing were tested, in which the initial maximum tensile strength of the material could reach 7.9 MPa, and the maximum tensile strength after self‐healing was 7.3 MPa, with a repair rate of 91.8%; the maximum elongation was 585.9%, and the maximum elongation after self‐healing was 469.5%, with a repair rate of 80.1%. In addition, this material has excellent repair performance for microcracks of different scales, and the micromolten part of the surface after heating can fill the micrometer cracks, play the role of antiaging, and extend the service life of the material.

Damage quantification of a metallic beam under thermo-mechanical loads using novel empirical correlations and neural network

This research examines the interactions between fracture depth and crack location on a cantilever beam’s dynamic response under thermomechanical loads. The structure’s stiffness is significantly influenced by temperature, and changes in stiffness can alter the response’s damping, frequency, and amplitude. The basis for measuring damage to an Aluminium 2024 specimen under thermomechanical loads is provided by these variations. Cantilever beams are used in experiments that are carried out at elevated temperatures, such as 50°C, 100°C, 150°C, and 200°C, as well as at room temperature (non-heating). This analysis takes into account a cantilever beam with different initial fracture depths and positions. The outcomes of the experimental, analytical, and numerical work are found to be in good accord. This research mainly fill the gaps of recent techniques for structure health monitoring of metallic structures where the coupled loads exist. Dynamic response formulation is presented experimentally on beam for the first time under thermo-mechanical loads. The dynamic parameters vary with material stiffness, thus; this change is also investigated by introducing the temperature as a key variable using a specially designed temperature controller. A novel technique is presented for damage estimation in metallic structures using the experimental data that is currently accessible which is later compared with the neural network approach. This tool helps in finding out and quantifying damagesusing dynamic response, temperature along withfinding of subsurface cracks. The results establisha clearway of diagnosing the crack growth at any particular instant under thermo-mechanical loads within the operational condition.