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Replacement of missing dentition is one of the common reasons to attend a dental practice for individuals who wish to restore their aesthetics and function. There are a variety of treatment modalities for the replacement of a single missing tooth that is a removable of partial denture, a fixed partial denture or an implant supported restoration. Each of these treatment options have their own advantages and disadvantages. Adequate clinical experience becomes a most important factor for treatment planning in fixed and removable prosthodontics. The cantilever fixed partial denture is defined as a restoration having one or more abutments at one end while the other end of the restoration remains unsupported. Anterior teeth replacement can be effectively done using a short-span cantilevered fixed partial denture. Studies report that conventional cantilevered fixed prostheses of various designs have a survival rate of 82% over a 10 year period and cantilevered resin-retained prosthesis show survival rates 83 92% during a 5 year period. While treatment planning for fixed cantilever bridges, there are aesthetic, design and occlusal considerations that should be kept in mind to achieve successful treatment outcome. These are discussed in this paper. Also included, is a clinical case report of a patient that had fixed cantilever prosthesis replacing the maxillary left central incisor with good aesthetic and functional results. Geriatric patients prefer the comfort of a cantilever fixed partial denture to a removable partial denture, since less maintenance is required at subsequent appointments. However, with the rapid advancement in implant dentistry, the use of cantilever fixed partial dentures may be decreasing. This article outlines the basic clinical considerations which may be applied during treatment for fixed cantilever bridges. Key Words: Cantilever bridges; clinical treatment planning; tooth replacement; fixed prosthodontics.

The concept of bilateral cantilevers on a single central implant (T-design) for three-unit implant-supported fixed dental prostheses (ISFDPs) has not been explored nor tested. This technical hypothesis aimed to explore the feasibility of such an approach as a cost-effective alternative to conventional treatments. Careful considerations regarding implant diameter, length, ideal position, occlusal scheme, and bone remodeling are essential to ensure adequate support, stability, and prevention of complications. In this proof of concept, we present a preliminary case with this novel design to replace missing posterior teeth in a patient with narrow bone conditions. In addition, a series of planned investigations and preliminary results, including preclinical studies, are presented to illustrate our concept and its potential clinical implications. Clinically, after two-year follow-up, healthy and stable peri-implant tissues around the ISFDP exemplarily demonstrated excellent stability, functionality, and comfort, which is supported by acceptable fracture resistance data in vitro, suggesting indeed the practical potential and suitability. Thus, we claim that such a treatment modality has the at least theoretical potential to revolutionize implant dentistry by providing innovative and cost-effective treatment options for patients with partial ISFDPs in very specific cases. Of course, further research and evaluations are necessary to validate the clinical implications of this innovative hypothesis. Implementing the 3-on-1 T-bridge approach in partial ISFDPs could offer a promising alternative to traditional methods. If proven successful, this technique may lead to significant advancements in clinical practice, providing a less invasive cost-effective treatment option., (Copyright 2024 SWISS DENTAL JOURNAL SSO – Science and Clinical Topics. License: This work is licensed under a Creative Commons Attribution 4.0 International License.)

Copyright of Roads & Bridges / Drogi i Mosty is the property of Road & Bridge Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction. Management of missing maxillary lateral incisors can be a challenging endeavour for dentists. Whether from agenesis or tooth loss, several treatment modalities are currently present to tackle this task to ensure satisfactory aesthetics. Most patients, especially younger patients are more likely to prefer fixed prosthodontic rehabilitation. Among these options is the computer-aided design and computer-aided manufacturing polymethyl methacrylate (CAD/CAM PMMA) cantilever bridge. Case Descriptions. These two clinical cases describe the management of missing lateral maxillary incisors in two Tunisian female patients with different etiologies, using CAD/CAM PMMA cantilever bridge. Conclusions. CAD/CAM technologies allow for a fairly quick and simple try-in thanks to their high accuracy as well as being predictable, minimally invasive, and affordable treatment options. This type of restoration can be put to use for mid- to long-term solutions to missing maxillary lateral incisors. However, its success depends mainly on patient selection regarding age, general health, occlusal context, and proper indication.

An approximate method for sizing continuity tendons in cast-in-place segmental cantilever box girders is presented in this technical note. Variables investigated are the length of the main span, the length of the continuity tendons, and the geometry of the box girder. Results indicate that secondary moments due to the prestressing of the continuity tendons decrease as the span length increases and as the length of continuity tendon decreases. For girders with a curved soffit, it was found that the type of variation of the girder depth (e.g., parabolic, cubic) has a small effect on the magnitude of the secondary moments. [ABSTRACT FROM AUTHOR]

Post-tensioned balanced cantilever reinforced concrete (RC) bridges allow the economic spanning of wide spans using fewer columns than in more traditional bridges. More and more post-tensioned balanced cantilever bridges are constructed every year all round the world. The aim of this study was to investigate numerically the effects of near-fault vertical ground motions (VGMs) on the seismic behaviour of segmentally constructed, balanced cantilever RC bridges. Two long bridges constructed in Artvin, Turkey – the three-span Budan Bridge and the two-span Sengan Bridge – were selected for the application. Three-dimensional finite-element models (FEMs) of the bridges were created to obtain their dynamic characteristics such as natural frequencies and mode shapes numerically. The frequencies calculated from the FEMs of the bridges were then verified using experimental frequencies measured from ambient vibration tests. Acceleration records of near-fault earthquakes (1992 Erzincan (M = 6·69), 1999 Kocaeli (M = 7·51), 1999 Düzce (M = 7·14) and 1989 Loma Prieta (M = 6·93)) were selected for the seismic analyses. The seismic behaviours of the verified FEMs of the bridges with two and three spans were determined by considering horizontal, vertical and combined horizontal and vertical components of the earthquakes. It was found that near-fault VGM significantly affects the seismic response of segmentally constructed, balanced cantilever bridges. [ABSTRACT FROM AUTHOR]

This paper highlights the development and validation of two innovative modular cantilever (MC) designs for railway overhead applications. Existing MCs are heavy, complex, and prone to failures. Addressing these shortcomings, the proposed designs leverage topology optimization and TRIZ principles to achieve significant improvements: weight reduction: Up to 28% lighter than existing MCs due to optimized material distribution. Enhanced robustness: Improved structural efficiency and strength, reducing failure risk. Simplified assembly and maintenance: fewer components and modular design facilitate easier handling and installation. Environmental resistance: increased durability against fatigue cracking, corrosion, and wear and tear. Numerical calculations and finite element analysis validate the performance of the new designs, confirming their ability to withstand dynamic loading conditions equivalent to traditional MCs. These lightweight, robust, and adaptable solutions offer tremendous potential for reducing costs, improving safety, and optimizing performance in railway overhead applications. [ABSTRACT FROM AUTHOR]

Piezoresponse Force Microscopy (PFM) is capable of detecting strains in piezoelectric materials down to the picometer range. Driven by diverse application areas, numerous weaker electromechanical materials have emerged. The smaller signals associated with them have uncovered ubiquitous crosstalk challenges that limit the accuracy of measurements and that can even mask them entirely. Previously, using an interferometric displacement sensor (IDS), we demonstrated the existence of a special spot position immediately above the tip of the cantilever, where the signal due to body-electrostatic (BES) forces is nullified. Placing the IDS detection spot at this location allows sensitive and BES artifact-free electromechanical measurements. We denote this position as x I D S / L = 1 , where x I D S is the spot position along the cantilever and L is the distance between the base and tip. Recently, a similar approach has been proposed for BES nullification for the more commonly used optical beam deflection (OBD) technique, with a different null position at x O B D / L ≈ 0.6 . In the present study, a large number of automated, sub-resonance spot position dependent measurements were conducted on periodically poled lithium niobate. In this work, both IDS and OBD responses were measured simultaneously, allowing direct comparisons of the two approaches. In these extensive measurements, for the IDS, we routinely observed x I D S / L ≈ 1 . In contrast, the OBD null position ranged over a significant fraction of the cantilever length. Worryingly, the magnitudes of the amplitudes measured at the respective null positions were typically different, often by as much as 100%. Theoretically, we explain these results by invoking the presence of both BES and in-plane forces electromechanical forces acting on the tip using an Euler–Bernoulli cantilever beam model. Notably, the IDS measurements support the electromechanical response of lithium niobate predicted with a rigorous electro-elastic model of a sharp PFM tip in the strong indentation contact limit [ d e f f ≈ 12 pm / V , Kalinin et al., Phys. Rev. B 70, 184101 (2004)]. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW)-layered materials, such as graphite, exhibit unique mechanical properties owing to their structural and mechanical anisotropies. This study reports the development of a mechanical model that reproduces the characteristics of the nonlinear and reversible bending deformation of vdW-layered materials, while taking into account the microscopic mechanism of the discrete interlayer slips. The vdW-layered material was modeled as a stack of interacting discrete deformable layers (semi-discrete layer model), and the interlayer interaction was modeled using a cohesive zone model that reproduced the localized interlayer slip. Using the finite-element method, out-of-plane bending deformation analyses were performed on the cantilevers of the highly oriented pyrolytic graphite (HOPG) and MoTe2, and the validity of the model was verified by comparing it with the experimental results. The model accurately reproduced the loading and unloading behaviors in the experiments for the submicron HOPG cantilevers or the large nonlinear and reversible deformation with a hysteresis loop. Furthermore, the model reproduced well the characteristics of the bending experiments for the micro-MoTe2 cantilevers, or the intermittent decrease in stiffness during the loading process and deformation restoration during the unloading process. These results demonstrated that the designed semi-discrete layer model can be universally applied to reproduce the bending deformation characteristics of a variety of vdW-layered materials and can be employed to effectively elucidate the underlying deformation mechanisms. [ABSTRACT FROM AUTHOR]

Bridges are vital assets of transport infrastructure, systems, and communities. Damage characterization is critical in ensuring safety and planning adaptation measures. Nondestructive methods offer an efficient means towards assessing the condition of bridges, without causing harm or disruption to transport services, and these can deploy measurable evidence of bridge deterioration, e.g., deflections due to tendon loss. This paper presents an enhanced input-doubling technique and the Artificial Neural Network (ANN)-based cascade ensemble method for bridge damage state identification and is exclusively relying on small datasets, that are common in structural assessments. A new data augmentation scheme rooted in the principles of linearizing response surfaces is introduced, which significantly boosts the efficiency of intelligent data analysis when faced with limited volumes of data. Furthermore, improvements to a two-step ANN-based ensemble method, designed for solving the stated task, are presented. By adding the improved input-doubling methods as simple predictors in the first part of the cascade ensemble and optimizing it, we significantly boost accuracy (7%, 0.5%, and 8% based on R2 in predicting tendon losses for three critical zones that were defined across the deck of a real deteriorated prestressed balanced cantilever bridge). This improvement is strong evidence of the accuracy of the proposed method for the task at hand that is proven to be more accurate than other methods available in the international literature. [ABSTRACT FROM AUTHOR]

Context: Airborne pathogens, defined as microscopic organisms, pose significant health risks and can potentially cause a variety of diseases. Given their ability to spread through diverse transmission routes from infected hosts, there is a critical need for accurate monitoring of these pathogens. This study aims to develop a sensor by investigating the vibrational responses of cantilever and bridged boundary-conditioned single-layer graphene (SLG) sheets with microorganisms, specifically SARS-CoV-2, attached at various positions on the sheet. The dynamic analysis of SLG with different boundary conditions and lengths was conducted using the atomistic finite element method (AFEM). Simulations were performed to evaluate SLG's performance as a sensor for biological entities. Altering the sheet's length and the mass of the attached biological object revealed observable frequency differences. This sensor design shows promise for enhancing the detection capabilities of graphene-based technologies for viruses. Methods: Finite element method (FEM) analysis is employed to model the sensor's performance and optimize its design parameters. The simulation results highlight the sensor's potential for achieving high sensitivity and rapid detection of SARS-CoV-2. Bridged and cantilever boundary conditions are applied at the ends of the SLG structure by using ANSYS software. Simulations have been conducted to observe how SLG behaves when used as sensors. In armchair graphene, under both boundary conditions, an SLG (5, 5) structure with a length of 50 nm displayed the highest frequency when a SARS-CoV-2 molecule with a mass of 2.6594 × 10−18 g was attached. Conversely, the chiral SLG (17, 1) structure exhibited its lowest frequency at a length of 10 nm. This insight is crucial for grasping detection limits and how factors such as size and boundary conditions influence sensor efficacy. These biosensors hold immense promise in biological sciences and medical applications, revolutionizing patient care by enabling early detection and accurate pathogen identification in clinical settings. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The continuous improvement of bridge construction technology has resulted in an ongoing expansion of bridge spans, which has concomitantly increased the difficulty of controlling the alignment of long-span bridges during construction. In order to address the issue of the grey prediction model exhibiting a significant discrepancy in its alignment predictions for long-span continuous girder bridges, a pre-camber prediction method for bridges based on a combination of the grey model (GM) and BP neural network (GM-BP) is proposed. Firstly, the parameters are identified according to their influence on the pre-camber, and the appropriate parameters are selected as the original data to improve the efficiency of prediction. Subsequently, the original data are preliminarily fitted by the GM(1,1) model, and the predicted values are used as inputs for training the neural network. Finally, the new predicted values are output using the nonlinear fitting ability of the BP neural network. To assess the efficacy of the model, it is applied to the prediction of the pre-camber of the girder segments of a bridge under cantilever construction. The pre-camber prediction for 11#–13# girder sections was based on 10 sets of monitoring data from constructed girder sections. The results demonstrated that the average relative error of the GM-BP combined prediction model was 3.01%, which was 5.68% less than that of the GM(1,1) model, and the overall prediction exhibited a closer alignment with the original data. The GM-BP combined prediction model is an effective method for ensuring the alignment control of bridge construction and is able to achieve high accuracy and stability in its predictions in the case of limited and irregular data. [ABSTRACT FROM AUTHOR]

The article presents a retrospective study about the rehabilitation of partially edentulous patients using cantilever bridges. Among several methods of preparing dentitions for partially edentulous patients, is a cantilever bridge, which has it own failure rate. While analyzing the failures of cantilever bridges, it was ascertained that they occurred both due to biological and technical causes. The study was done taking into consideration, 136 patients who had cantilever bridges fitted between 1963 and 1985, who were then called for follow-up. It was found that when the periodontal tissue was insignificantly reduced, at least two abutment teeth were used as anchors combined with one or two extension units. Biological failures were found to be 23.3% and technical failures at 12.7%.

To investigate the automatic monitoring technology of key construction nodes and structures of super-large bridges constructed with cantilever, the 0# block radar measurement and control, the settlement monitoring of construction sections and the mechanical response monitoring of whole bridge were carried out during the deformation and stress stages of the cantilever construction bridge section. The measurement and control data of stress and deformation in actual construction and simulation data were compared and analyzed, and the safety state of bridge section during construction was judged by the coincidence. By the mathematical statistics method, the accuracy of radar monitoring data was compared with that of traditional monitoring data. The research results show that radar monitoring can work around the clock and can analyze typical fluctuations in cloud images in combination with construction logs. The fitting value of millimeter-wave radar monitoring block 0# deformation data is 0.051 44, which is better than 0.006 32 of the traditional monitoring method and has stronger correlation with the numerical simulation curve. During the whole construction period, the monitoring data of the force and deformation of each segment of the whole bridge fluctuate around the theoretical values with small fluctuation range, and the continuous beam is always in safe state. [ABSTRACT FROM AUTHOR]

The article reports in the application of gantry machines in pre-cast segmental balanced cantilever bridges. It discusses their generic forms along with the impact they have on permanent structure and design of the bridge. It highlights their components with consideration of their effect on cost and productivity. It describes the advantages of expenditure, quality and programmes of their utilization. It also points the benefits of separating their design from supply.

The timber lounge bridge with cantilever beams is a kind of bridge architectural heritage that is different from the simply supported timber beam bridge and timber arch lounge bridge in typology. It has important historical, artistic, and scientific values. For the preventive protection and repair of the timber lounge bridge with cantilever beams, this paper proposes a scientific and reliable quantitative evaluation method for its structural safety status, taking the typical timber lounge bridge with cantilever beams, Yongqing Bridge, as a case study. The evaluation consists of three stages: firstly, analyzing the typology of the timber lounge bridge with cantilever beams and recording the deterioration; secondly, establishing the evaluation system and grading criteria for the timber lounge bridge with cantilever beams; thirdly, using the finite element method to calculate the importance of the components and quantitative evaluating the structural safety status of the timber lounge bridge with cantilever beams by using the improved analytic hierarchical process (IAHP) and making the final decision. The results of this study can provide a scientific basis for quantitative evaluation of the structural safety status, preventive protection, and repair of the timber lounge bridge with cantilever beams. [ABSTRACT FROM AUTHOR]

Some arms of nanorobots display L-shaped structures. The transverse free bending vibration of an L-shaped cantilever nanobeam carrying a tip nanoparticle is investigated. Based on the nonlocal elasticity, the nonlocal parameter is introduced to capture the size effect of the mechanical behavior of the cantilever–mass system. The frequency equation is deduced analytically. Exact resonance frequencies of the L-shaped nanocantilever–mass system are numerically evaluated and compared with their corresponding values of the macro-scale L-shaped cantilever–mass system. The numerical results show that the nonlocal parameter declines the resonance frequencies. If removing the nonlocal parameter, our results reduce to the resonance frequencies of transverse bending vibration of L-shaped cantilevers with an attached tip mass. The effects of the nonlocal parameter, the ratio of the attached mass to the structure mass, the length ratio of two members of the L-shaped cantilever–mass system on the resonance frequencies are analyzed. [ABSTRACT FROM AUTHOR]

BACKGROUND: All-ceramic cantilever bonded bridge has become a hot topic in the clinical aesthetic restoration of anterior teeth due to its advantages in treatment time, invasiveness, aesthetics and price. OBJECTIVE: To summarize the solutions to the clinical technical difficulties of all-porcelain cantilever bonded bridge and its advantages in the application of anterior teeth, and to introduce the clinical follow-up methods of the existing all-porcelain cantilever bonded bridge, in order to provide clinical and scientific guidance in the field of aesthetic repair of partial dentition defects of anterior teeth. METHODS: The articles published from 1955 to 2021 were retrieved by the first author on Web of Science, PubMed, CNKI, and Wanfang databases. The English search terms were “denture, partial, fixed, resin-bonded, resin bonded bridge, Maryland bridge, adhesive bridge, single-retainer, all-ceramic”. The Chinese search terms were “bonded bridge, Maryland bridge, adhesive bridge, all-ceramic, cantilever, single-retainer”. Totally 60 articles were summarized for review after screening. RESULTS AND CONCLUSION: (1) Effective surface pretreatment with zirconia ceramic material could prevent the occurrence of fracture. Designing the retention form of the box-shaped hole near the gap side and the nail hole at the bulge of the tongue is one of the current consensus of experts, which can effectively reduce the occurrence of bonded bridge shedding and improve the long-term retention effect. Under the condition of meeting the indications, the all-ceramic cantilever adhesive bridge has the advantages of low incidence of complications such as caries and periodontal disease, good aesthetic effect, and long retention time, and can be used as a permanent restoration. (2) For clinical studies, in addition to counting the basic success rate of retention rate, it is recommended to simultaneously use the oral health-related quality of life questionnaire, satisfaction questionnaire, and the American Public Health Association prosthesis evaluation criteria to comprehensively evaluate the repair effect. (3) It should be noted that different studies have defined the retention rate and success rate differently, which makes certain deviation for data statistics. Therefore, the actual clinical effect of all-ceramic cantilever bonded bridge is worthy of further investigation. [ABSTRACT FROM AUTHOR]

Wooden cantilever covered bridges are known for their marvelous shapes and manufacturing technique. Many wooden cantilever covered bridges were constructed during Ming and Qing Dynasties in Anhua province, China, due to the "Tea-Horse Trade" policy. The excellent performance of wooden materials and exquisite building techniques have kept these wooden bridges well-preserved and worthy of investigation. This paper conducted a comprehensive review of wooden cantilever covered bridges in Anhua, especially for the eight bridges listed as historical and cultural heritage protected at the provincial or the national level. The discussions covered the historical background of the bridges, their locations and dimensions, and the details of their structures including the cantilever systems, corridors, and roofs. Moreover, the cultural background was introduced to better understand the meaning of the decorations carved on the bridges and the logic of location selections. [ABSTRACT FROM AUTHOR]

Deck caps of bridges—in Germany shortly known as "bridge caps"—are usually made of steel reinforced concrete to form the anchoring area for the guardrail of bridge deck edges on existing cantilever slabs. Combined with protective devices, the outside arranged deck caps provide safety against lateral breaking or crashes of vehicles. Due to their exposed position in the cross section of bridges and the particularly intensive stresses, the deck caps are considered as wear parts and have to be renewed several times during the service life of a bridge. The decisive factor here is the discrepancy between the frost resistance of the concrete and the crack width restriction. On the one hand, only very small cracks (<0.2 mm) can be accepted to prevent corrosion of the rebars under the strong exposure of these elements. To confine crack widths without applying an excessively high degree of reinforcement, a low concrete compressive strength is advantageous. On the other hand, a sufficient frost resistance requires a correspondingly high compressive strength. With carbon reinforcement, these contrary points could be defused and simultaneously the needed durability could be provided. Therefore, slightly modified deck cap concretes combined with a carbon reinforcement mesh were tested to examine the bond behavior with and without freeze–thaw attack. To prove the characteristics of this combined system, the crack formation and crack distribution were investigated experimentally. The test results were compared to calculated values from a mathematically tool to be able to develop different reinforcement concepts in future that can ensure an optimized crack formation and crack width for deck caps. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the use of a single Astra Tech implant to support a two-unit cantilever fixed dental prosthesis. Materials and method: Twenty-nine subjects with an edentulous space (at least equivalent to two bicuspid units) in the premolar/molar segments of the maxilla or mandible with opposing natural teeth or a fixed/removable prosthesis were treated. They were provided with either a 4 or 5.0 mm diameter fixture MT OsseoSpeed. Prostheses were constructed using a cast-to abutment as a one-piece unit with porcelain fused to precious metal to allow direct screw retention. Results: Subjects expressed a high satisfaction with treatment, including appearance and function. The most important complication was abutment screw loosening. It occurred as a single episode in four subjects and in another six subjects the loosening was recurrent. Bone levels were stable and there were no significant differences in radiographic bone height between cantilever and non-cantilever sides of the implant at any time point. Conclusion: Single implants can be successfully used to support two-unit cantilever FDPs in the premolar region. A common factor could not be identified in relation to abutment screw loosening. To cite this article: Palmer RM, Howe LC, Palmer PJ, Wilson R. A prospective clinical trial of single Astra Tech 4.0 or 5.0 diameter implants used to support two-unit cantilever bridges: results after 3 years. Clin. Oral Impl. Res. 23, 2012; 35-40. doi: 10.1111/j.1600-0501.2011.02160.x [ABSTRACT FROM AUTHOR]

A satellite with two solar wings can be modeled using a pair of symmetric flexible cantilever beams connected to a central rigid body. Due to certain reasons, the symmetric flexible cantilever beams may be turned into asymmetric ones, which will inevitably influence the vibration properties of the structural system. By changing the structural sizes and adding local mass on one side of the two beams, a structural system with asymmetric mass distribution is obtained and its vibration characteristics are investigated. Hamilton's principle with the assumed mode method is employed to establish the equation of motion of the asymmetric structural system. The natural frequencies, mode shapes, frequency response curves and displacement time histories of the system are calculated, and they are compared with those of the structural system with a symmetric mass distribution. The correctness and feasibility of the present analytical method are verified by means of the finite element method (FEM) and a vibration experiment. The analytical results show that the mass asymmetry of the two beams leads to the mode localization phenomenon, and the coupling effect between the two beams and the central rigid body is enhanced. The larger the mass asymmetry is and the closer the position of the added local mass to the end of the cantilever beam is, the more obvious of the mode localization phenomenon is and the more obvious of the coupling effect between the two beams and the central rigid body is. The present investigation results are helpful for the dynamic analysis and design of spacecraft structures composed of flexible solar wings and a central rigid body. [ABSTRACT FROM AUTHOR]

Propped cantilever truss is not a common bridge construction technique. The performance of such bridges under operational and extreme loading is not reported in the literature either. In this paper, failure mechanisms in a propped cantilever truss bridge are reported using field investigation. The field observations are supplemented by numerical analysis to identify the causes of failure. A a systematic account of damage mechanisms in bridge components is also reported. The failure of the Lamgadi Bridge over the Seti River in Nepal is used as a case study example. The loading and construction protocols are detailed, and numerical analysis results are juxtaposed with the field observations to explain the failure mechanisms. Field observations and numerical results show that lack in adequate design is the most likely cause of the bridge collapse. Numerical results also indicate that the roller support at the propped end, unlike the hinged pot bearing used in the as constructed bridge would have been a safer choice. The failure could have been easily prevented with proper numerical simulation of the bridge response during the design phase. [ABSTRACT FROM AUTHOR]

Abstract: The yawing moment acting on the box-girder deck of reinforced concrete bridges constructed using the balanced cantilever method during the erection stage has been experimentally analyzed by testing different types of bridge cross-sections. Experimental results show that the yawing moment coefficient decreases as the bridge decks become streamlined, and that the yawing moment coefficient reaches a maximum when the bridge deck length is nearly twice the deck width. [Copyright &y& Elsevier]