Longitudinal Cracks Research Articles

Experiment and numerical study on the static and fatigue behavior of a novel deck joint

To increase the prestressing efficiency and alleviate the longitudinal cracking in the concrete slab of composite cable-stayed bridges, a novel deck joint was proposed. The joint is composed of epoxy joint and concrete wet joint, which allows to introduce the prestress before the precast deck slabs are connected to the steel girder, therefore significantly increases the prestressing efficiency. Full-scale test models were fabricated and tested under repeated negative bending load, with the main variables being prestress level and fatigue load amplitude, and the evolutions of displacement, strain, crack width and moment distribution were investigated. A numerical study was conducted to investigate the effects of joint geometries and prestress level on the joint strength, the moment distribution and the neutral axes. The failure mechanism of the joint was revealed and a calculation method was recommended. Results show that the failure modes of the test models are rebar fracture in the tension zone, and the prestress has significant benefits on the joint behavior. The moment distribution between the precast and the post-cast sections is affected by the prestress level and the width ratio of epoxy and wet joints. The recommended method can predict the static flexural resistance of the joint with accuracy.

EVALUATION OF THE LEVEL OF ROAD DAMAGE IN JELIDRO II-KUWUKAN-SAMBIKEREP ROADS USING THE PAVEMENT CONDITION INDEX (PCI) AND BINA MARGA METHOD

The road is a facility for land transportation that serves regional development. The deterioration of road quality can pose constraints on economic and social activities and endanger road users. Small damages can escalate if not promptly addressed, leading to losses. This reasearch aims to determine the type and level of damage on Jelidro II – Kuwukan - Sambikerep Roads STA 0+000 to STA 1+600. There are two methods for obtaining road condition values in this research, the methods are Pavement Condition Index method and the Bina Marga method. On the section of Jelidro II – Kuwukan - Sambikerep Roads, 8 types of damage were found, those are crocodile skin cracks, grade depression, edge cracks, potholes, patches, longitudinal cracks, slip cracks, and ravelling. The results of calculating the road condition value using the PCI method is 63,6 where the road is included in the good category. Calculations using the Bina Marga method get a priority order of 9. The two methods show that the road has the same type of treatment, that is a routine maintenance program with repair methods that can be carried out, namely surface layers such as asphalt resurfacing and patching holes. Keywords: Road Damage; PCI method; Bina Marga method.

Plastic zones for ductile layer sandwiched between two different substrates

This study is an extension of previously developed models of plasticity occurring in the vicinity of ​​a longitudinal crack in a thin elastic-plastic layer sandwiched between two identical, ideally elastic substrates: Varias–Suo–Shih [1], Rogowski-Molski [2], and Rogowski [3]. The solution presented in the current study describes the plastic zone size problem in a thin constrained layer bonded to two different substrates. A well-known two-term K-T Williams [4] stress solution for interfacial cracks is used to obtain the plastic zone size. A new equation with coefficients dependent on the layer and substrate material properties was obtained, allowing for the calculation of the plastic zone size in the thin ductile layer based on the values of the complex stress intensity factor K and T-stresses. The proposed model is tested for several arbitrarily selected interfacial crack geometries, load conditions, bonding layers, and substrate material properties. Because of the complicated oscillatory description of the local stress field, the final solution of the mathematical equation is obtained numerically, ignoring a small zone of intense stress oscillations near the crack tip. Good agreement is obtained between the results from the proposed model and the FEM results in terms of quantity and quality. A novel approach may be utilized in the future as a method for estimating the parameter of fracture criterion for bonded joints.

Characterizing damage evolution in fiber reinforced composites using in-situ X-ray computed tomography, deep machine learning and digital volume correlation (DVC)

In-situ X-ray computed tomography (CT) techniques enable to examine microstructural evolution of composite materials continuously and nondestructively under loading for better understanding the initiation and propagation of microscopic damages. This study explores the tensile damage behavior of notched woven carbon/epoxy composites under successive loading process. Since the image contrast of different composite material phases is normally low and conventional image segmentation techniques are hard to identify microstructures and defects in different directions distinctively, a U-Net image segmentation model based on deep machine learning algorithms is employed to characterize microstructures and material damages precisely and consistently. Digital volume correlation (DVC) approach is proposed here tocharacterize the three-dimensional (3D) deformation fields of carbon/epoxy composites at different loading steps, and the DVC results are used to predict location of damage initiation and propagation. It is found that the damage modes of notched carbon/epoxy composites mainly include fiber breakage, longitudinal cracks in warp fiber tows, and transverse cracks in weft fiber tows. The individual fiber breakage occurs in warp fiber tows at the intermediate loading level, and longitudinal and transverse cracks appear in further loading levels. Longitudinal cracks and fiber breakage events take place in a region tangent to the notch tip and exhibit a strong interaction. The development of longitudinal cracks promotes the initiation and propagation of transverse cracks. In addition, the strain concentration regions in 3D deformation fields match well with the microscopic cracks segmented by the U-Net deep learning model. This study demonstrated that the integration of X-ray computed tomography, digital volume correlation and image semantic segmentation enables to identify damage initiation, evolution, extent and mechanism.

Effect of the Hole Diameter in Mechanical Properties of Wood: Experimental and Numerical Approaches

Introducing openings or holes into wooden structures is a common practice for providing utility services. However, this practice leads to stress concentration, resulting in a reduction in stiffness and load-carrying capacity. Therefore, understanding the effects of holes on beam properties is important for design considerations. This study investigates the mechanical behavior of a wooden beam made from juvenile Pinus elliottii containing open cylindrical holes with three different diameters: 4, 8, and 12 mm. The mechanical properties were evaluated for compression parallel to the fibers, quasi-static bending, and tension perpendicular to the fibers. Numerical simulations were conducted using a finite element (FE) model, considering the orthotropic elastic properties determined from experimental tests and elastic ratios reported in the literature. The experimental results indicated that the influence of hole diameter was not significant on the compressive properties; however, longitudinal crack failures began to form for holes with diameters of 8–12 mm. Regardless of hole size, the compressive and bending characteristics revealed that hole location did not affect the stiffness, strength, or damage mechanisms.

Revolutionising Egyptian pavement design: a comprehensive E* database and advanced modeling approach for contextually informed performance predictions

ABSTRACT This research assesses the dynamic modulus (E*) as a pivotal rheological attribute for characterizing viscoelastic behaviour in various indigenous asphalt mixtures across diverse scenarios. An exhaustive investigation involving 32 laboratory-designed asphalt mixes and two field mixes explores the influence of traffic loading patterns, air voids, binder sources, and climatic conditions on E*. Utilizing Superpave gyratory compaction, 68 E*-specimens are compacted and subjected to E*-testing, leading to master curve development. Evaluation of NCHRP 1-37A and NCHRP 1-40D Witczak models demonstrates their fair to excellent accuracy in predicting E* for Egyptian mixes. The NCHRP 1-40D model stands out with an R² of 0.94, showcasing superior accuracy and minimal bias. This study integrates AASHTOW are Pavement ME Design (PMED) to analyse pavement sections, revealing the impact of design factors, characterized by measured E*, on predicted pavement performance, encompassing asphalt concrete rutting, alligator cracking, longitudinal cracking, and terminal international roughness index. The investigation highlights the marginal impact of substituting predicted E* for measured E* on AASHTOWare pavement performance indicators for Egyptian mixes under default binder characteristic values. This research contributes valuable insights into the interplay of E* and pavement performance, facilitating wellinformed decisions in pavement design and analysis across diverse conditions in the Egyptian context.

Kajian Analisis Desain Teknis Pemeliharaan Jalan Beton Desa Maluku Kec. Maritengngae Kab. Sidrap

Road maintenance or upkeep is not an easy problem to do because it requires quite a large amount of money. This is what causes the government to appear slow in repairing road damage so that the damaged roads become worse and wider. In reality, so far the government has carried out road maintenance and repairs when the road was in a condition that was in serious disrepair, so it is certain that the costs required will be very large and it can also be ascertained that the losses suffered by road users while the road is damaged, are also very large. big or even worthless. However, in implementing the preservation program, proper management is required so that the preservation program can be carried out effectively and efficiently. The aim of this research is to determine the type of damage found on concrete roads in Maluku Village, Kec. Maritengngae District. Sidrap along 2 km and technical study of concrete road maintenance program in Maluku Village, District. Maritengngae District. Sidrap along 2 km. The results of the research show that the damage on the concrete road in Maluku Village, Kec. Maritengngae District. Sidrap has patch damage, edge damage, cracks, transverse cracks, longitudinal cracks and holes. The most dominant damage is damage to holes and damage to roads on the concrete road in Maluku Village, Kec. Maritengngae District. Sidrap has 2 types of treatment, including Periodic Maintenance and Routine Maintenance Program. And handling the most dominant type of damage from STA 0+000 to 2+000 is a routine maintenance program of 100%.

Maintenance Strategy for the Muliama-Wa2e-Makki Road Section in Jayawijaya Regency, Papua Province, Highlands

In Jayawijaya Regency, there are several prioritized road sections, including national, provincial, and district roads. The Muliama-Wame-Makki road section is classified as a provincial road serving as an alternative route, with a total length of 22 kilometers connecting Jayawijaya Regency and Lanni Jaya Regency. The traffic on this road is quite heavy with a diverse composition (Mixed Traffic). An analysis using the Pavement Condition Index (PCI) was conducted based on field survey data, including measurements of the extent, types, and quantities of surface damage per 200 meters along each road segment. The types of damage observed on the Muliama-Wame-Makki road section include patching, longitudinal cracks, alligator cracking, and pavement subsidence, with a total damage percentage of 1.684%. The maintenance strategy is determined based on the PCI calculation and Bina Marga method, suggesting that routine maintenance is sufficient for addressing the observed issues.

Characteristics and Influence Rules of Roadside Ponding along the Qinghai–Tibet Highway

Due to climate change and seasonal precipitation, water conditions in the Qinghai–Tibet region are a significant factor affecting the stability of subgrades. The accumulation of large amounts of surface water leads to subgrade diseases along the Qinghai–Tibet Highway. Based on remote sensing photos obtained from Google Earth Engine and processing the photos using ENVI 5.6.3 and CAD 2019 software, this paper analyzed the distribution characteristics of surface water and studied the impact of roadside ponding on subgrade diseases. The results showed that the total area of surface water was more than 3.7 million m2, and the surface water was most widely distributed in large river areas such as the Tuotuo River and Buqu River. The subgrade diseases of the Qinghai–Tibet Highway could be categorized into three types: settlement, longitudinal crack, and frost boiling, which accounted for 71.09%, 17.13%, and 11.78% of the total number of subgrade diseases, respectively. Additionally, the ground mean annual temperature was an important factor affecting the distribution of surface water, with the surface water area showing an increasing trend with the increase in ground mean annual temperature, and roadside ponding was most likely to form in the high-temperature extremely unstable permafrost area.

Multiscale modeling of environment-dependent heterogeneous media by a Thermo-Hydro-mechanical damage model

Evaluating the combined environmental effects, such as external loads, water saturation, and thermal variations, on the mechanical performance of porous media is challenge, mainly due to its inherent heterogeneity and complex multi-physical field mechanisms. This study developed a multiscale thermo-hydro-mechanical damage modeling framework to investigate environment-dependent heterogeneous porous media, with a specific focus on pavement infrastructure. The notable features of this framework comprise: (1) introducing an upscaling homogenization method to connect material thermo-mechanical properties across various scales while considering seasonal variations, (2) creating a downscaling transfer procedure to translate structural responses and temperature fields from macroscopic to mesoscopic scales, providing insights into their multiphysics mechanisms at different scales, and (3) proposing a new sequential coupled algorithm in multiscale simulations for comprehensive multi-field cross-scale calculations. The key findings demonstrated that under hydro-thermo-mechanical loading, shear transverse damage occurs mainly at the macro media surface, while tension longitudinal cracks appear at the bottom of the meso-scale material layer. Damage patterns vary with seasons, with more shear damage prevalent during the summer and an increased occurrence of tension cracks during the winter. Additionally, water-saturated media are more susceptible to “down-top” cracking compared to dry ones. The proposed model can be easily extended to investigate the mechanical behaviors of various heterogeneous porous media under a range of environmental conditions.

Vibration monitoring and acoustic emission sensing during progressive load tests of corroded reinforced concrete beams

Corrosion of reinforcement in concrete civil structures poses a significant challenge to their integrity and durability. To ensure the safety and longevity of such structures, effective monitoring strategies that can accurately detect, localise and assess the progression of damage are crucial. For most existing concrete structures, this is often challenging, as damage is already present when the monitoring campaign starts. In addition, reinforced concrete structures can be subject to a combination (or a succession) of corrosion and load-induced damage. By combining multiple measurement techniques, a more accurate and reliable condition assessment of concrete civil structures can be aimed for. This paper presents a comprehensive experimental study of the combination of vibration-based monitoring (VBM) and acoustic emission (AE) sensing techniques during progressive load tests of corroded reinforced concrete beams. Five beams were subjected to a cyclic four-point bending test, three of which were previously corroded while two beams remained undamaged prior to the mechanical loading. The influence of pre-existing corrosion damage and corresponding longitudinal concrete cracking on the modal characteristics (natural frequencies and strain mode shapes) and AE outcomes is investigated during the four-point bending test. The monitoring results obtained by both techniques are shown to be influenced by the pre-existing longitudinal concrete cracking caused by the reinforcement corrosion. Lower AE activity and a lower reduction in natural frequencies is observed for corroded RC beams during load bending tests when compared to uncorroded specimens. In addition, bending cracks occurring within the corroded zones appear to have a very limited effect on the identified strain mode shapes. These observations could possibly result in an underestimation of the damage and corresponding overestimation of the load-carrying capacity, as the corrosion damage conceals the occurrence of bending cracking on the AE and VBM outcomes.

The analysis and design of jointed plain concrete pavements with wider slabs

Despite the cost-effective nature of asphalt pavements, concrete pavements are preferred for their superior serviceability. Many agencies use Jointed Plain Concrete Pavement (JPCP) designs with a standard slab size of 3.5 × 4.5 m, focusing on transverse cracking. However, night-time Longitudinal Top-Down Cracking (LTDC) can occur in widened slabs due to tandem and tridem axles. This study employs a Finite Element (FE) approach to assess wider slabs under various loads. Longitudinal tensile stresses at critical points were found to increase with the slab width. Therefore, the study emphasizes the need for a design approach addressing transverse and longitudinal cracking. The design of the wider slabs (4.5 × 4.5 and 5.0 × 4.5 m) is demonstrated using a case study. If the longitudinal joint in a 9.0 m slab is placed at 5.0 m from the edge, the pavement could perform better than other slab sizes. However, it is necessary to design the pavement considering both longitudinal and transverse cracking.

Experiment and Numerical Simulation on Thermal Cycling Performance of YSZ-Based Sealing Coatings with “Brick-Mud” Layered Structure

The failure of premature thermal cycling spalling off is the bottleneck problem currently faced by yttrium oxide partially stabilized zirconia (YSZ) ceramic-based sealing coatings. Studies on the thermal cycling performance of coatings with “brick-mud” structures were carried out by experimental and simulation methods in this paper. The results showed that, as the thickness of “mud” layer increased, the bonding strength of the “brick-mud” structure coatings gradually decreased. When the thickness of the “mud” layer was about 3 μm and 10 μm, the thermal cycling lives of the T1 and T2 coatings were improved by 90.0% and 135.7%, respectively, compared with conventional coating (T0 coating), while that of the T3 coating (containing thick “mud” layers of about 20 μm) was decreased by 81.4%. The stress field of M2 “mud” layers with different thicknesses was subjected to a comprehensive effect by thermal mismatch stress and pores in “brick” layer. Compared with the medium and thick “mud” layers, the thin “mud” layer sustained obvious larger σ22 max and σ12 max, indicating its potential for the preferential initiation of transverse microcracks. In addition, the thin “mud” layer withstood the largest σ11 max and had the strongest potential for longitudinal crack growth. Both transverse and longitudinal cracking could consume energy during thermal cycling and reduce the stress concentration at the top coating/bond coating interface. These were the main reasons for the improvements in the thermal cycling performances of the T1 and T2 coatings. The degree of crack deflection and the capacity of energy dissipation in the “mud” layer increased significantly with its thickness. However, the propagation length of transverse cracks also gradually increased in the meantime. Especially when the “mud” layer was 20 μm, the length of the transverse cracks increased rapidly. Thus, early interlayer delamination failure occurred in the T3 coating during thermal cycling.

Investigations on the effect of natural veined calcite on the mechanical properties of limestone.

The damage behavior of limestone rock masses containing calcite mineral filling under uniaxial compression experimental conditions is unclear, and the fracture mechanism of the rock masses needs to be further explored. In this study, uniaxial compression tests were conducted on limestone rock specimens containing veined calcite by combining acoustic emission and digital image correlation techniques. The effects of veined calcite on the generation and development of cracks on the surface of the specimens until the formation of macroscopic penetration and the strength properties of the rock mass were analyzed. The results showed that the transversely distributed veined calcite caused significant stress concentrations in the rock specimens. The longitudinally distributed veined calcite caused cracks in the specimens or influenced the expansion path of the longitudinal principal cracks. The final damage pattern of the specimens didn't differ significantly from that of conventional rock masses due to the presence of veined calcite. The presence of the veined calcite had effect on the uniaxial compressive capacity of the rock, but the load variation process of the specimen with time still conformed to the load variation pattern during the uniaxial compressive test of conventional rocks.

Degradation of RC Columns under Combined Exposure to Axial Loading, Stray Currents, and Chloride Ingress.

Coastal regions, home to a significant portion of the world's population, confront a formidable challenge: the corrosive impact of chloride-rich environments on vital infrastructure. These areas often host essential transportation systems, such as trains and metros, reliant on pre-existing electrical infrastructure. Unfortunately, complete isolation of this infrastructure is rarely feasible, resulting in the emergence of stray currents and electrical potentials that expedite corrosion processes. When coupled with conducive mediums facilitating chemical electrocell formation, the corrosion of reinforced concrete elements accelerates significantly. To combat this issue, international standards have been established, primarily focusing on augmenting the thickness of reinforcement bar covers and restricting stray voltage between rails and the ground. Nevertheless, these measures only provide partial solutions. When subjected to service loads, these elements develop cracks, especially when exposed to stray currents and chlorides, dramatically increasing corrosion rates. Corrosion products, which expand in volume compared to steel, exert internal forces that widen cracks, hastening the deterioration of structural elements. The study deals with the degradation of reinforced concrete columns under the combined action of loads, chloride-rich environments, and electrical voltage-simulating stray currents. In these conditions, degradation and reduction of load-bearing capacity accelerate compared to unloaded conditions, significantly amplifying the corrosion rate. Astonishingly, even in the absence of mechanical loads, stray currents alone induce tensile stresses in elements due to corrosion product formation, leading to longitudinal cracks parallel to the reinforcement bars.

Machine Learning Modeling of Wheel and Non-Wheel Path Longitudinal Cracking

Roads degrade over time due to various factors such as traffic loads, environmental conditions, and the quality of materials used. Significant investments have been poured into road construction globally, necessitating regular evaluations and the implementation of maintenance and rehabilitation (M&R) strategies to keep the infrastructure performing at a satisfactory level. The development and refinement of performance prediction models are essential for forecasting the condition of pavements, especially to address longitudinal cracking distress, a major issue in thick asphalt pavements. This research leverages multiple machine learning methods to create models predicting non-wheel path (NWP) and wheel path (WP) longitudinal cracking using data from the Long-Term Pavement Performance (LTPP) program. This study highlights the marked differences in distress conditions between WP and NWP, underscoring the importance of precise models that cater to their unique features. Aging trends for both types of cracking were identified through correlation analysis, showing an increase in WP cracking with age and a higher initial International Roughness Index (IRI) linked to NWP cracking. Factors such as material characteristics, kinematic viscosity, pavement thickness, air voids, particle size distribution, temperature, KESAL, and asphalt properties were found to significantly influence both WP and NWP cracking. The Exponential Gaussian Process Regression (GPR) emerged as the best model for NWP cracking, showcasing exceptional accuracy with the lowest RMSE of 89.11, MSE of 7940.72, and an impressive R-Squared of 0.63. For WP cracking, the Squared Exponential GPR model was most effective, with the lowest RMSE of 12.00, MSE of 143.93, and a high R-Squared of 0.62. The GPR models, with specific kernels for each cracking type, proved their adaptability and efficiency in various pavement scenarios. A comparative analysis highlighted the superiority of our new machine learning model, which achieved an R2 of 0.767, outperforming previous empirical models, demonstrating the strength and precision of our machine learning approach in predicting longitudinal cracking.

Fitness-for-Service assessment of a Hydrogen-Induced crack in an inlet gas separator pressure vessel using computational modelling

Hydrogen-induced cracking is the cracking of carbon steel or low-alloy steel in a wet H2S environment, driven by the diffusion of hydrogen atoms into the steel due to corrosion reaction. The formation of blisters and hydrogen-induced cracks in pressurized components in the oil and gas or petrochemical industries imposes a serious risk to personnel safety and production continuity. In this study, a fitness-for-service assessment of a gas separator pressure vessel containing 3.76 % H2S and 3.47 % CO2 was analyzed using finite element analysis as required by level III assessment in API 579–1/ASME FFS-1 2021. Different load scenarios, including internal pressure, static head from liquid, dead weight, and wind loads, were considered using elastic-perfectly plastic stress analysis. The hydrogen-induced affected area, with dimensions of 2650 mm × 900 mm, was shown to sustain an internal pressure of 14.8 MPa, which is above 1.35 times the design pressure (i.e., 12.1 MPa). The assessment of API 579–1/ASME FFS-1 in level I and II failed due to the presence of a hydrogen-induced crack near the weldment. However, the evaluation in level III assessment considered the influence of residual welding stresses on both longitudinal and circumferential cracks in their as-welded state. The findings indicated that the affected area fell within the acceptable region of the failure assessment diagram, thereby confirming the continued safe operation of the HIC damaged pressure vessel while accounting for welding residual stresses.

Damage of a post-tensioned concrete bridge – Unwanted cracks of the girders

The cracking of a post-tensioned T-beam superstructure, which was built using the incremental launching method, is analyzed in the paper. The problem is studied in detail, as specific damage was observed in the form of longitudinal cracks, especially in the mid-height zone of the girder at the interface of two assembly sections. The paper is a case study. A detailed inspection is done and non-destructive testing results of the girders are briefly discussed. The attention is especially focused on advanced and comprehensive numerical simulations of the bridge mechanical behavior. Linear and nonlinear static calculations are performed employing the Finite Element Method at global and local levels of precision, enabling deep insight into the bridge response during all the stages of bridge construction and after it is opened to traffic. The crack propagation process in local analyses is described by the application of the Concrete Damage Plasticity law, the parameters of which were carefully chosen. The predicted damage patterns closely resemble those observed at the site. The results reveal, that the girder damage process was initiated when centric prestressing was applied, because vertical reinforcement of the assembly section front-end surface was not designed. However, the damage did not compromise the safety of the bridge. Finally, the repair methods employed are described and also a discussion is presented on how to prevent the occurrence of such cracking.

Effect of local bond behavior degradation on tension stiffness in reinforced concrete with pre-existing longitudinal cracks

Reinforced concrete structures often have cracks when exposed to corrosion of rebars. This induced crack can deteriorate the bond capacity between concrete and rebar, affecting the structural performance of the member. This study conducted pull-out and uniaxial tension tests on cracked specimens to investigate the effect of bond behavior degradation on the tension stiffening effect. It uses an innovative approach to simulate concrete cracking by inserting an aluminum pipe into the concrete and filling it with an expansion agent to replicate the volumetric expansion caused by rebar corrosion. The local bond-slip behavior degradation is modeled using Popovics formulation based on pull-out cracked bond specimens. Furthermore, uniaxial tension tests reveal that induced cracks decrease transverse crack numbers and reduce the tension stiffening effect, primarily due to bond loss. However, this degradation becomes insignificant after a total deformation of 1.5 mm, corresponding to about 0.1% in average strain. Finally, analytical results confirm that tension stiffness does not necessarily decrease with increased induced crack width. Instead, the tension stiffness may increase in case of high bond loss due to induced crack.

Detecting deck damage in concrete box girder bridges using mode shapes constructed from a moving vehicle

Longitudinal cracks at the bottom of the deck are a common form of hidden damage in box girder bridges. Timely detection of deck cracking is critical to ensure the safe operation of box girder bridges. This paper proposes a damage detection method for the deck of box girder bridges using mode shapes constructed from a moving vehicle. One stationary excitation vehicle excites the local bending modes of the deck, and the other vehicle moves along the planned path. The moving vehicle acceleration is collected to construct mode shapes on the driving path. First, generalized beam theory is used to analyze the dynamic behavior of the box girder bridge. The theoretical model of the proposed approach is built to analyze the response of the vehicle-bridge system under shaker excitation, and mapping relationship between the instantaneous amplitude of the vehicle response and the local bending mode of the deck is deduced. The damage indicator based on the mode curvature is used to determine the crack position. Then, a damage detection process for field testing is proposed. Technical details such as excitation parameters, driving path, and narrowband filtering are explained. Finally, factors that affect damage detection, including road roughness, crack length, and crack height are investigated via numerical analysis. Results show that the proposed method can detect medium damage.