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Background: Mandibular second premolar agenesis is a common problem in orthodontics and is often treated in conjunction with maxillary counterbalancing extractions. However, in cases without maxillary crowding or dental protrusion, space closure may pose challenges leading to compromised occlusal results or patient profile. Multiple techniques have been described to treat these patients; nevertheless, there is a paucity of data comparing effectiveness of space closure utilizing various anchorage techniques. The goal of this study is to assess the effectiveness of the Herbst device during mandibular molar protraction and compare it to the use of temporary anchorage device (TADs) in patients with mandibular second premolar agenesis. Materials and methods: This retrospective study included 33 patients with mandibular premolar agenesis treated without maxillary extractions. Of these patients, 21 were treated with protraction Herbst devices and 12 with TADs. Changes in molar and incisor positions, skeletal base positions and occlusal plane angulations were assessed on pretreatment (T0) and post-treatment (T1) lateral cephalograms. Scans/photographs at T0 and T1 were used to evaluate canine relationship changes representing anchorage control. Space closure and breakage/failure rates were also compared. Data was analyzed with paired and unpaired t-tests at the significance level of 0.05. Results: Within the Herbst group, changes in mandibular central incisor uprighting and mandibular molar crown angulations were statistically significant. However, no significant differences were noted between the Herbst and TAD groups. Protraction rates as well as overall treatment times were comparable (0.77 mm/month vs. 0.55 mm/month and 3.02 years vs. 2.67 years, respectively). Canine relationships were maintained or improved toward a class I in 82.85% of the Herbst sample, compared to in 66.7% of the TAD sample. Emergency visits occurred in 80.1% of the Herbst group, with cementation failures or appliance breakages as the most common reasons. Conclusion: The Herbst device could be a viable modality in cases with missing mandibular premolars where maximum anterior anchorage is desired, or if patients/parents are resistant to TADs. Furthermore, they could be beneficial in skeletal class II patients with mandibular deficiency who also need molar protraction. However, the increased incidence of emergency visits must be considered when treatment is planned. [ABSTRACT FROM AUTHOR]

AbstractIn case of strong seismic-induced vibration, some metallic support and anchorage systems may exhibit elastoplastic deformation. To consider this elastoplastic deformation in the seismic design of equipment, standards such as CEN/TS 2004 recommend a very simplified behavior coefficient which is constant. Neither post-elastic characteristics such as the hardening coefficient, the ductility capacity, nor the dynamic content of the equipment are considered so far in this approach. In this paper, the influence of the elastoplastic deformation in supports on equipment responses is examined by means of a systematic numerical analysis. As highlights, the effect of elastoplastic supports strongly depends on the frequency of the equipment and the post-elastic characteristics. In certain cases, the effect of elastoplastic deformation in supports can be ‘unfavorable’ with respect to the assumption of elastic supports. This is the case for support-equipment systems of high frequency for which it is recommended to limit elastoplastic deformation. Conversely, for flexible support-equipment systems, it is beneficial to explore the ductility capacity of metallic supports. Finally, for engineering applications, behavior coefficients to consider the elastoplastic deformation in supports are proposed in the format of an abacus as a function of ductile capacity, hardening coefficients, and dimensionless frequencies of the equipment. [ABSTRACT FROM AUTHOR]

When modelling the anchorage performance of rebars with the tri-linear law, the calculation process of the load–deformation relation is complicated. The reason is that when the rebar–grout interface entered the elastic–softening–debonding stage, the softening section length and debonding section length vary simultaneously. To solve this issue, this paper proposes an enhanced numerical calculation method. When the rebar–grout interface entered the elastic–softening–debonding stage, the softening section length was fixed to a specific value. One loop function was created to calculate the debonding section length. With this method, the number of iteration calculations significantly decreased. The credibility of this calculation method was confirmed with experimental results. Two case studies were conducted to compare the load–deformation relation obtained with the original calculation method and enhanced calculation method. The results showed that good consistency existed between the results obtained by those two methods. This finding can significantly improve the calculation efficiency when studying the anchorage performance of rebars. Moreover, this paper provides new insight for users to optimise the modelling process of rebars. [ABSTRACT FROM AUTHOR]

Soil nails and tieback anchors are used extensively for excavation support and slope stabilization; however, their performance can be complicated by limited pullout capacity or installation challenges. This paper presents the results of field load tests performed on anchorage elements with snakeskin-inspired surfaces that do not require grout and that can reduce the force required for installation. These tests evaluated the effects of the asperity geometry, soil type, and embedment depth on the anchor load transfer behavior and pullout capacity. The tests consisted of jacked installation and pullout loading in sites consisting of dense sand and structured silt. The test results in sand indicate that the installation force and pullout skin friction increase as the asperity height is increased and the asperity length is decreased. The pullout capacity of the snakeskin-inspired anchors in sand was between 1.2 and 4.2 times greater than the capacity of a reference rough anchor. In the structured silt site, disturbance during installation influenced the pullout behavior, resulting in a decrease in anchor capacity as the asperity height was increased. However, the anchor capacity with small asperity heights was greater than that of the reference rough anchor. The snakeskin-inspired anchors mobilized direction-dependent skin friction, resulting in pullout skin friction values that were as much as 3.0 and 4.5 times greater than those generated during installation in the sand and silt sites, respectively, due to mobilized passive resistances during pullout. The results indicate that the snakeskin-inspired anchors can outperform conventional driven anchors in sands. However, the possible effects of installation disturbance should be evaluated carefully in sensitive, structured soils. [ABSTRACT FROM AUTHOR]

Every football statue transcends mere physical representation; it stands as a public monument constructed to commemorate and honor specific subjects. The football statue involves an intricate interplay of communication factors and functions, potentially transforming into a message imbued with encyclopedic signs to serve its communicative purposes. Importantly, the football statue, as a communication phenomenon, extends beyond a simple semiotic relation between the statue and a viewer. We must also consider the addresser's intentions, including strategies for engaging the viewer as an addressee. This duality involves referencing both historical and spatial contexts (the physical environment) beyond the message itself. And various semiotic means – also poetic – capture the viewer's attention and maintain contact. We understand the semiotics of football statues from the perspectives of Eco (encyclopedia, intentio auctoris, model reader), Jakobson (communication model), Peirce (icon, index, symbol, collateral experience), and Barthes (relay, anchorage). Our analytical descriptions/examples solely concern UK statuary after an examination of 89 statues. [ABSTRACT FROM AUTHOR]

Based on the shortcomings of traditional bolts in the process of supporting surrounding rock, the structural composition and working principle of new bolts have been studied in detail. The working principle of the new bolt is divided into the elastic deformation stage and slip stage, and the energy constitutive equation of the corresponding stage is analysed. Then, Abaqus software is used to numerically simulate the working state of the bolt under static tension. With increasing drawing load, the maximum axial stress of the bolt and the von Mises stress of the surrounding rock first increased and then tended to stabilize, and the maximum axial displacement of the bolt gradually increased. The axial stress of the bolt was concentrated at the damping module, and the stress was mainly concentrated at the front damping module. The deformation of the bolt is mainly concentrated in the damping module of the first section, and the deformation of the bolt decreases rapidly with increasing anchoring depth. On-site pull-out tests confirmed that the drawing force of the new bolt increased by 128% and 24% compared with that of the pipe bolt and the left handed without longitudinal rebar bolt, respectively. The novel bolt has the characteristics of high strength and large displacement, which allows it to support the surrounding rock well and has good application prospects. [ABSTRACT FROM AUTHOR]

In the construction of the Shenzhen--Zhongshan Link, a temporary anchorage system, distributed uniformly along the pipe wall, has been employed. To assess the safety and reliability of this system, a combined method utilizing numerical analysis and model experiments was applied to study the safety of the temporary anchorage system and the reliability of the tension rods. Firstly, an overall model of the caisson segment based on GINA rebound force was established to analyze the stress state of the entire system. Secondly, a comprehensive numerical analysis and model experiment verification were conducted for the single tensioning system, revealing its failure mode and safety margin. The results indicate that the tension rod systems are uniformly stressed at an average of 444 kN during underwater jointing, with a safety factor of 1.94. At this point, the maximum von Mises stresses appearing at the front plate corners and the lower edge of the U-groove, with stress values of 181.8 MPa and 172.4 MPa, and safety factors of 1.54 and 1.71, respectively. When the tension rod force reaches 940 kN, the tensioning system reaches its bearing limit, with initial yielding occurring at the front plate corners. Model experiments were conducted to verify the theoretical analysis results, under a test load of 444 kN, the stresses at the front plate corners and the lower edge of the U-groove were 159.6 and 195.9 MPa, respectively. As the test load increased to 940 kN, these stresses reached 390 and 389 MPa, exhibiting good agreement with the numerical analysis. Considering the uncertainty of loads and materials, a reliability analysis of the tension rods was conducted, yielding a reliability index of 4.34, meeting the secondary safety standard. Based on the comprehensive analysis, it can be concluded that the temporary anchorage system in the caisson segments of the Shenzhen--Zhongshan Link exhibits excellent safety margins. [ABSTRACT FROM AUTHOR]

With the increase in port throughput and the development of the trend of large-scale ships, selecting applicable anchor positions for ships and ensuring the rational and comprehensive utilization of anchorage areas have become a key issue in utilizing the rate of anchorage resources, ensuring the safety of ships anchoring operations and promoting the development of the shipping industry. Existing anchor position selection and detection algorithm studies are limited to a two-dimensional plane for ship anchor position selection, with few studies considering intelligent detection algorithms for safe ship anchoring water depths based on three-dimensional space, considering conditions such as wind and waves. By considering water depth conditions and the objectives of anchorage safety issues, this study proposes an intelligent detection method for ship anchor detection to find the ship's ideal anchor location in the anchorages by applying the Monte Carlo algorithm. In the processing step, in combination with the Monte Carlo random plane anchor position detection algorithm and Monte Carlo random sampling water depth detection method, the anchor position circle radius model, safe spacing model, anchoring area detection model and safe water depth model are used for examining the anchorage area for awaiting the ship in three-dimensions. To verify the accuracy of the proposed model, based on the scale of common ship types and considering the most conservative parameters, a series of simulation experiments are conducted to check whether the water depth meets the requirements and fully ensure the safety of the experimental results. The research results indicate that the detection almost cover the whole anchorage area and obtain safe water depth restrictions. This method helps to improve the efficiency of ship anchoring and makes actual anchoring operations safer. Under the premise of ensuring sufficient safe spacing between ships, the anchorage ground can accommodate more ships and simulate multi-type ship anchor position detection operations concerning various ship-type parameters to further ensure the safety of ship anchoring. [ABSTRACT FROM AUTHOR]

This study introduces an innovative wedge anchor for double-layer carbon fiber reinforced polymer (CFRP) plate cable to address the current limitation of traditional wedge anchors. By employing the design concept of "secondary force transmission path", the friction force for anchoring the CFRP plate is effectively transferred into the barrel through its contracting wedge, thus reducing the clamping pressure requirement of traditional wedge anchorage for anchoring thick or double-layer CFRP plates. Based on this conception, this study presents a theoretical analysis model for predicting the influence of parameter variations on the compressive stress of the CFRP plate, which can serve as a tool for rapid configuration preliminary design. Through finite element analysis, the internal stress distribution of the anchor is thoroughly investigated, and the theoretical analysis model for fast predicting compressive stress of CFRP plate is also validated. The results also indicate that the anchorage conception is valid and effective, providing sufficient anchorage of CFPR plates with an anchorage length of 100 mm. [ABSTRACT FROM AUTHOR]

Since the fall of the Saddam Hussein regime in 2003, Iraqi Shi’a political actors have been the main forces leading the country, dominating the domestic legislative scene over their Sunni and Kurdish counterparts. This article brings innovative analysis and classification of actors, such as Islamic Da’wa Party, Badr Organization, Asa’ib Ahl al-Haq (AAH), Harakat Huquq, Al-Hikma, Islamic Supreme Council of Iraq (ISCI), Sadrist Movement, or Imtidad, bringing more light on the Iraqi political scene since the parliamentary elections in 2021. The ideological anchorage of the parties is evaluated in two dimensions, religious and sectarian, placing them on the Islamic-secular and sectarian-nationalist axes, reflecting their approach towards intra-religious issues, vilayet al-faqih, possible normalization of relations with Israel, sectarianism, and nationalism. The methodology of this research is based on Chapel Hill Expert Survey data collection, semi-structured interviews with politicians and political experts from the Kurdistan Region of Iraq and Iraq, Jordan, and the United Kingdom, content analysis of examined actors’ statements on social and official media and opinion polls, reflecting the voices of the Iraqi society. The main results of this research singled out clusters of more pro-Iranian actors (Badr Organization, AAH, Harakat Huquq), with the highest tendency to use Islamic and sectarian policies, followed by more traditional Iraqi political actors such as Islamic Da’wa Party and ISCI. Al-Hikma, Sadrist Movement and Imtidad then inclined to be more nationalist and secular. Finally, it shows the Iranian influence as a crucial factor in shaping the domestic and foreign policies of thoseactors. [ABSTRACT FROM AUTHOR]

Although plain round or square section reinforcement is no longer used in new construction, there are many older structures still in service built with such bars. In recognition of the need for guidance on the assessment of load‐carrying capacity of structures reinforced with such bars, design codes are now introducing or re‐introducing provisions to assess the capacity of laps and anchorages of such reinforcement. The authors have contributed to the introduction of design rules in the fib Model Code 2020. This paper describes the derivation of these provisions. Starting from the form of expression proposed earlier by the authors, the data from which these proposals are derived is specified and modifications in interpretation preparatory to a statistical analysis are outlined. A rigorous multivariate statistical procedure is then employed firstly to determine a mean strength expression for the capacity of anchorages and laps which is then validated against test data. Further statistical analysis is subsequently used to determine a design expression using the approach outlined in EN 1990, taking appropriate account scatter in test data. Finally, some comparisons are presented between the assessment expressions proposed and design provisions that were in place when these types of bars were in common use. Areas where earlier design provisions may be non‐conservative are identified. [ABSTRACT FROM AUTHOR]

In this paper, steel–polyethylene hybrid fiber-reinforced strain-hardening cementitious composites (HECC) are applied in beam–column external joint core region to form a novel HECC/reinforced concrete (RC) composite beam–column joint with reduced anchorage length of beam longitudinal rebar and eliminated transverse rebar, and thus to alleviate rebar congestion and simplify the construction process efficiently especially for precast RC frame structures. Five external beam–column joint specimens are constructed and tested under cyclic loading to illustrate the influences of the anchorage length of beam longitudinal rebar and longitudinal rebar ratio on the seismic performance of beam–column joint. The effects of design parameters on seismic performance, including hysteresis behavior, degradation of strength, energy dissipation capacity, and cracking patterns are discussed in detail. Experimental results indicate that the replacement of normal concrete with HECC in beam–column joint core region could apparently reduce the amount of stirrups in the joint core area while maintaining reliable seismic behavior. Remarkably, specimen with no stirrups in the core area exhibits nearly equivalent seismic behavior to that of the control RC specimen. Furthermore, the application of HECC in joint core area allows for a substantial reduction of the required anchorage length for the beam longitudinal rebar to 9d, which further simplifies the construction process considerably. [ABSTRACT FROM AUTHOR]

This paper explores the China-US relationship through a thematic analysis of 781 YouTube comments on the China-US Anchorage Summit. Guided by the six conditions of Dahlberg's model of an ideal online public sphere, this study has found: first, the emerged themes from the selected comments fit in with Dahlberg's six conditions in terms of gratitude, opposition, reflection, respect, accuracy, and inclusion. Second, the YouTube platform presents the online commentators an ideal public sphere for active and meaningful interactions with one another, thus showcasing that an online public sphere is feasible, practical, and ideal. As implications, the research findings herein reinforce the validity of Dahlberg's model by showcasing YouTube as one of the most important social media outlets which materializes the existence and facilitates the operation of an ideal online public sphere. Meanwhile, the research findings also shed light onto further explorations of the online social media and genuine understanding of the developmental trajectory of the China-US relationship. [ABSTRACT FROM AUTHOR]

Coal‐measure strata is a typical layered structure, a better understanding of the bearing characteristics of fully grouted bolts in layered rock mass is of great significance for roadway support. However, limited studies have been conducted to investigate the bearing performance of fully grouted bolts in layered rock mass. In this paper, a numerical model of fully grouted bolt in layered rock mass was established, and a tri‐linear bond–slip model of the anchorage interface was imported into the numerical model by the user‐defined Fish language. The effects of strata sequence, strata thickness, and strata number in layered rock mass on the bearing performance of fully grouted bolts were systematically analyzed. The results show that fully grouted bolts in soft–hard type (SH‐type) layered rock mass has higher bearing capacity. The greater the thickness of the soft rock in the layered rock mass, the more significant the influence of the strata sequence on the bearing performance of fully grouted bolts. The bearing capacity of fully grouted bolts decreases with the increase of the thickness ratio of soft rock to hard rock. The greater the thickness of the hard rock in the layered rock mass, the more beneficial to the bearing performance of fully grouted bolts. With the increase of the strata number, the bearing capacity of fully grouted bolts gradually decreases. For bolt support of layered rock mass, the deep anchoring foundation of fully grouted bolts should be arranged in hard rock or elastic zone rock as much as possible, and rock grouting can be adopted to reduce the difference in mechanical properties between layered rock mass and improve the durability of fully grouted bolts. The research results may provide useful guidance and reference for the support design of fully grouted bolts. [ABSTRACT FROM AUTHOR]

Anterior open bite (AOB), characterized by the lack of vertical overlap between upper and lower anterior teeth, poses a considerable challenge in orthodontics. The condition depends on many factors that combine to render it difficult to achieve post treatment stability. AOB is commonly classified as dental, skeletal, or functional on the basis of the clinical presentation and causative factors. Traditionally, skeletal AOB necessitates surgical intervention, whereas nonsurgical approaches such as extrusion arches and the Multiloop Edgewise Archwire Technique (MEAW) can be employed in more straightforward cases. Functional appliances are reserved for situations in which a patient's growth potential offers the possibility of effectively addressing AOB. This review presents a strategic treatment approach for addressing AOB, taking into account the classification and severity of the condition. The proposed SHE framework describes the use of mini-screws (S) for anchorage and vertical control, encouragement to correct habits (H), and the utilization of extractions and elastics (E). By incorporating extra-radicular mini-screws, AOB closure is achieved through anterior retraction in extraction cases or whole arch distalization of dentition with elastics in non-extraction cases. This framework emphasizes habit correction through a regimen of oral myofunctional therapy (OMT) and habit-correcting appliances to enhance posttreatment stability. This review suggests that nonsurgical correction is viable in the majority of cases, whereas surgical intervention should be reserved for severe cases of skeletal vertical overgrowth or horizontal discrepancies. [ABSTRACT FROM AUTHOR]

Abstract Background Mandibular second premolar agenesis is a common problem in orthodontics and is often treated in conjunction with maxillary counterbalancing extractions. However, in cases without maxillary crowding or dental protrusion, space closure may pose challenges leading to compromised occlusal results or patient profile. Multiple techniques have been described to treat these patients; nevertheless, there is a paucity of data comparing effectiveness of space closure utilizing various anchorage techniques. The goal of this study is to assess the effectiveness of the Herbst device during mandibular molar protraction and compare it to the use of temporary anchorage device (TADs) in patients with mandibular second premolar agenesis. Materials and methods This retrospective study included 33 patients with mandibular premolar agenesis treated without maxillary extractions. Of these patients, 21 were treated with protraction Herbst devices and 12 with TADs. Changes in molar and incisor positions, skeletal base positions and occlusal plane angulations were assessed on pretreatment (T0) and post-treatment (T1) lateral cephalograms. Scans/photographs at T0 and T1 were used to evaluate canine relationship changes representing anchorage control. Space closure and breakage/failure rates were also compared. Data was analyzed with paired and unpaired t-tests at the significance level of 0.05. Results Within the Herbst group, changes in mandibular central incisor uprighting and mandibular molar crown angulations were statistically significant. However, no significant differences were noted between the Herbst and TAD groups. Protraction rates as well as overall treatment times were comparable (0.77 mm/month vs. 0.55 mm/month and 3.02 years vs. 2.67 years, respectively). Canine relationships were maintained or improved toward a class I in 82.85% of the Herbst sample, compared to in 66.7% of the TAD sample. Emergency visits occurred in 80.1% of the Herbst group, with cementation failures or appliance breakages as the most common reasons. Conclusion The Herbst device could be a viable modality in cases with missing mandibular premolars where maximum anterior anchorage is desired, or if patients/parents are resistant to TADs. Furthermore, they could be beneficial in skeletal class II patients with mandibular deficiency who also need molar protraction. However, the increased incidence of emergency visits must be considered when treatment is planned.

Objective To evaluate the clinical efficacy of clear aligner for crowded dentition in early permanent teeth by moving the upper and lower molars far. Methods A total of 36 adolescent patients with Class Ⅰ Angle malocclusion admitted in our department from March 2017 to August 2023 were enrolled, and they were 17 males and 19 females, and at a mean age of 13.20±0.53 years. Clear aligner was applied to push the upper and lower molars backward to obtain a neat dentition. Lateral cephalometric X-ray film before and after treatment was measured, and paired t-test was used to compare the cephalometric measurements before and after treatment. Results The average course of treatment was 21.2 months. Overbite, overjet and molar relationship were turned to normal after treatment, and the soft tissue profile was maintained. Analysis of relevant cephalometric items showed that the Ptm-U6 distance was decreased by 2.89±1.22 mm, and the Go-L6 distance was decreased by 2.61±1.07 mm after treatment, with significant differences (P < 0.01). While, there were no statistically differences in UL-EP, LL-EP, NLA and FCA before and after treatment. Conclusion With reasonable treatment target and good tooth movement design, clear aligner can effectively move the upper and lower molar distally to correct moderate dentition congestion in early permanent teeth, and meanwhile the patients' profile is maintained.

BACKGROUND: The reciprocal force generated by the molar distalization with clear aligners can lead to anchorage loss. The effect of arch shapes and missing second premolars on anchorage has not been reported. OBJECTIVE: To analyze the effect of arch shapes and missing second premolars on anchorage during molar distalization with clear aligners using the finite element method. METHODS: Cone-beam CT data from an adult male were acquired from the database to establish the maxilla-upper dentition-periodontium-rectangular attachment-clear aligner model. The distal movement amount designed on the bilateral second molars was set to 0.25 mm. First, there were two groups in the study: second premolar bilateral presence and absence groups. Then, four subgroups in each group were created: tapered arch, ovoid arch, square Class II Division 1 arch, and Class II Division 2 arch groups. The Ansys software was used to calculate the displacement of the anchorage tooth and the stress of the periodontal ligament. RESULTS AND CONCLUSION: Mesial tipping and extrusion of first molars and premolars, labial inclination and intrusion of anterior teeth occurred during the upper second molar distalization with clear aligners. When the bilateral second premolars were missing, the mesial displacement of first molars increased significantly while that of first premolars and anterior teeth decreased in all groups. The square Class II Division 1 arch group showed the least anterior labial inclination, while the tapered arch group showed the most. There was no significant difference between the ovoid arch group and the tapered arch group. Moreover, the magnitude of tipping in the square Class II Division 2 arch group was slightly higher than that in the Class II Division 1 arch group. The stress of the periodontal ligament of the anchorage teeth was concentrated on the cervical and apical regions of the teeth. And the lowest stress level was detected in the square arch group. Compared with the other groups, the stress on the labial cervical area of the periodontal ligaments was also significantly relieved in the square arch group. To conclude, the square arch is more favorable in terms of anterior anchorage control and periodontal ligament stress distribution. Anterior labial inclination efficiency can be increased in cases of Class II Division 2 by designing the anterior labial inclination in conjunction with molar distalization. If the second premolar is missing during molar distalization, it is not conducive to opening up the space in the area of the missing tooth. [ABSTRACT FROM AUTHOR]

Aim of study: This study aimed to use EDS (Energy Dispersive X-ray Spectrometry) in order to quantitatively and qualitatively assess secondary retention (osseointegration) by evaluating the elemental composition of the mini-implants (MIs) surface after their use as anchorage in orthodontic treatment, which could highlight possible osseointegration. Materials and methods: A total of 30 Infinitas™ mini-implants obtained from patients with an average age of 21.93 years, were analyzed using EDS. Scanning electron microscopy (SEM) was also performed to asses the mini-implants. Results: In all groups, new bone formation occurred between the threads of the MIs and the bone surface, partially extending along the thread. Fibroblast-like structures were observed using SEM. The Pearson correlation coefficient indicates that there is no significant correlation between %Ca and duration (coefficient = -0.085; p-value = 0.655). The atomic percentages of the elements on the MI surface, revealed from EDS analysis and also present in bone composition, are comparable to the percentages of elements in the alveolar bone from the study, according to Dunn’s Multiple Comparison test. Conclusions: The results suggest the presence of newly formed bone on the MIs surface

Abstract The paper describes the contracting and logistics conditions contributing to the level of anchorage in the grain, coal and fertiliser export trades of Vancouver. Increases in the level of anchorage in these trades have created economic, environmental and governance issues. Comparison of the logistics structures and practices in these commodity trades gives insights into the reasons for different levels of anchorage. Conditions in and data from the port of Vancouver are used to simulate conditions in the grain trade and to demonstrate the critical importance of the variability of ship loading times to levels of anchorage. The incidence of the costs of anchorage is examined. The terms in voyage charterparties used in the grain trade are found to inhibit efficient use of vessel time.

The generalized model and parameter equation for the internal fracture surface of tensile type anchor cable anchorage section are constructed, and the calculation model of ultimate bearing capacity is derived based on the principle of limit equilibrium. The shape of the internal fracture surface in the anchorage section and the expression of its parameter equation are experimentally studied, and the variation law of the parameter equation and fracture range with the diameter of the anchor cable and confining pressure is analyzed. The parameter equation is substituted into the calculation model to realize the calculation and verification of the model. Through theoretical derivation, a calculation model of ultimate bearing capacity of anchor cable is obtained, which comprehensively considers the average shear strength of anchorage section, the shape of fracture surface, fracture range and confining pressure. The tests show that according to the magnitude of the confining pressure on the anchorage section, the internal fracture surface takes on two shapes: cylindrical and trumpet‐shaped, the parameter equation of trumpet‐shaped fracture surface obeys logarithmic distribution approximately. The coefficient a decreases with the increase of confining pressure but increases with the increase of anchor cable diameter, the constant b increases with the increase of confining pressure but decreases with the increase of anchor cable diameter. The ranges of horizontal and vertical fracture decrease with the increase of confining pressure, and increase with the increase of anchor cable diameter. The deviations between the theoretical calculation and the experimental results are less than 6.5%. [ABSTRACT FROM AUTHOR]

The demand for strengthening reinforced concrete (RC) structures has increased considerably. Implementing carbon-fiber-reinforced polymer (CFRP) bars and concrete jacketing are the most effective techniques for RC beam retrofitting. Using the mechanical anchorage system (MAS) to attach CFRP bars to old concrete is highly recommended to avoid any debonding when it is applied to cyclic loads. However, the design of strengthening details is the most challenging issue because it involves many effective parameters. In this study, a design process for strengthening beams using CFRP bars with new MASs and concrete jacketing is proposed, and various design schemes are studied. The number of applied MASs and the thickness and grade of the concrete jacket were investigated through experimental testing and finite element (FE) simulations to define strengthening design details, such as the number and size of employed CFRP bars. Accordingly, an analytical technique was formulated to predict the performance of the strengthened beam in terms of the nominal ultimate load. The results demonstrated the high performance of the proposed system in preventing premature debonding. The proposed system enhances the beam capacity from 44 kN to 83 kN, representing an increase of more than 90%. In contrast, the conventional near-surface mounted (NSM) system exhibits a lower percentage increase at less than 37%. Both FE simulations and analytical approaches can be effectively employed to predict the behavior and capacity of the strengthened beam while considering various design parameters. [ABSTRACT FROM AUTHOR]

AbstractMiniscrews are temporary skeletal anchorage devices that are widely used in orthodontic treatment, and their success depends on the placement area, angle, technique, and screw dimensions. This study aimed to investigate the effects of miniscrew lengths, insertion angles, and force directions on a mandible model consisting of teeth, cortical and cancellous bones. One Dental Volumetric Tomography (DVT) scan from a patient who had miniscrews were used for mandibular bone modeling to perform finite element analysis. The model variables included miniscrew lengths (6, 8, and 10 mm), insertion angles (−15°, 45°, 60°, and 90°), and force directions (30°, 45°, and 60°). The minimum and maximum stresses were calculated as 18.61 and 37.11 MPa at 6 mm and 10 mm, respectively. According to the insertion angles, the lowest stress was observed at 60°, while the highest stress was found at 15° in the ventral direction. At force directions, the lowest stress was at 60°, and the highest stress was at 45°. However, there were no significant differences in insertion angles and force directions. A statistically significant difference was determined in miniscrew length. As a result, the best result was calculated to be 6 mm inserted at a 60° angle, which could induce the lowest stress. Increasing the miniscrew length will increase the stress on the mandible. In addition, because of the higher force direction, stress decreases with shorter power arms. [ABSTRACT FROM AUTHOR]

Although mechanically stabilized earth (MSE) walls typically require a reinforcement length-to-wall-height ratio of 0.7, the use of short reinforcement may be inevitable in certain situations, such as building MSE walls in mountainous areas, widening existing highways, or restoring eroded roadways. Intuitively, connecting the rear end of reinforcement in shored mechanically stabilized earth (SMSE) walls to the stable face behind can compensate for insufficient reinforcement anchorage length. However, the effectiveness of this approach remains debatable in the existing literature. This study aims to provide more complementary data and insight into the behavior of SMSE walls at a working stress state. A finite difference numerical model was first validated using measurements from centrifuge and full-scale tests. Then, a parametric study was conducted to evaluate the effects of wall geometry, reinforcement parameters, and backfill properties on the lateral facing displacement and maximum reinforcement tensile loads of SMSE walls. The numerical simulations show that, while connected conditions certainly improve the stability of the SMSE wall at the limit state, they may, counterintuitively, worsen the performance of the wall and increase the maximum reinforcement loads at working stress conditions, presenting a design dilemma. The reasons for the results obtained are discussed in detail, and optimized approaches are proposed to improve the performance of SMSE walls. [ABSTRACT FROM AUTHOR]

The interfacial bonding strength (IBS) of a reef limestone anchorage body at different curing ages was investigated based on pull-out and push-out experiments. By combining the experiments with dynamic impact disturbance, the damage evolution of the IBS for the reef limestone anchorage body was determined. The IBSs of the bolt-mortar (B-M) interface and reef limestone-mortar (R-M) interface increase logarithmically with curing age: IBSs are positively correlated with curing age. Under the effect of impact disturbance, the IBSs of two types of anchorage body both show a descending tendency; while as the curing age increases, the impact-resistant capabilities of the anchorage body are enhanced, accompanied by the gradual decrease of interfacial damage. Hence, engineering activities characterized by strong dynamic disturbance should be avoided as much as possible at early curing ages of the limestone anchorage body in engineering practice. In the meanwhile, the calculations using wave velocities to denote rock damage deviate significantly from the real damage strength of anchorage body interfaces. Therefore, one should be cautious in adopting damage thresholds for an anchorage body calculated using wave velocities. [ABSTRACT FROM AUTHOR]

An experimental campaign was undertaken to characterize the mechanical properties of newly proposed aluminum alloy ribs (ARs)-anchored glass fiber–reinforced polymer (GFRP) bars via tensile, short beam shear and pullout tests. The investigated variables consisted of bar surface treatments (smooth, shallow-ribbed, and deep-ribbed) and anchorage design parameters (radial extrusion and initial wall thickness). The results derived from the tensile test showed that the tensile strength of the ARs-anchored GFRP bars could be designed and optimized by adjusting the radial extrusion and initial wall thickness of the anchorage. The short beam shear test further validated that the presence of the ARs on the GFRP bar increased its interlaminar shear strength by up to 25%. The pullout test conducted on specimens with favorable anchorage design parameters based on tensile and short beam shear tests demonstrated significantly high bond strengths between 11.45 and 46.63 MPa at the bar–anchorage interface, with enhancements ranging from 60% to several times compared with that of the bar–concrete interface under different parameter combinations. The proposed ARs-anchored GFRP bars present an effective alternative to conventional GFRP bars in applications where a short anchorage length is preferred. [ABSTRACT FROM AUTHOR]

Structural damage in the steel bridge anchorage, if not diagnosed early, could pose a severe risk of structural collapse. Previous studies have mainly focused on diagnosing prestress loss as a specific type of damage. This study is among the first for the automated identification of multiple types of anchorage damage, including strand damage and bearing plate damage, using deep learning combined with the EMA (electromechanical admittance) technique. The proposed approach employs the 1D CNN (one-dimensional convolutional neural network) algorithm to autonomously learn optimal features from the raw EMA data without complex transformations. The proposed approach is validated using the raw EMA response of a steel bridge anchorage specimen, which contains substantial nonlinearities in damage characteristics. A K-fold cross-validation approach is used to secure a rigorous performance evaluation and generalization across different scenarios. The method demonstrates superior performance compared to established 1D CNN models in assessing multiple damage types in the anchorage specimen, offering a potential alternative paradigm for data-driven damage identification in steel bridge anchorages. [ABSTRACT FROM AUTHOR]

Four exterior reinforced concrete beam–column joint subassemblages with poor reinforcement details and low-quality materials were constructed and subjected to cyclic lateral deformations under constant axial loading of the columns. The longitudinal rebars at the top of the beams were well-anchored in the joint region with a 90° hook and transversely welded to prevent premature slippage. The same was true for the longitudinal rebars at the bottom of the beam of the first specimen. Contrarily, the anchorage of the rebars at the bottom of the beam of the other three subassemblages was straight and of insufficient length. One of these specimens (the second) also had deficient lap splices of the column reinforcement, while the other three specimens had continuous column rebars. The third and the fourth subassemblage were designed with different joint aspect ratio and beam shear span/depth ratio values. The overall seismic performance of the specimens was evaluated and compared. The failure mode of the subassemblages was accurately predicted by the proposed analytical model. It was clearly demonstrated that the anchorage of the rebars, the length of the lap splices, the joint aspect ratio and the shear span/depth of the beam ratio value crucially affect the cyclic response of beam–column joints and, hence, may cause a severe detrimental impact to the overall structural integrity. [ABSTRACT FROM AUTHOR]

Reducing waiting times is crucial for ports to be efficient and competitive. Important causes of waiting times are cascading interactions between realistic hydrodynamics, accessibility policies, vessel-priority rules, and detailed berth availability. The main challenges are determining the cause of waiting and finding rational solutions to reduce waiting time. In this study, we focus on the role of the design depth of a channel on the waiting times. We quantify the performance of channel depth for a representative fleet rather than the common approach of a single normative design vessel. The study relies on a mesoscale agent-based discrete-event model that can take processed Automatic Identification System and hydrodynamic data as its main input. The presented method's validity is assessed by hindcasting one year of observed anchorage area laytimes for a liquid bulk terminal in the Port of Rotterdam. The hindcast demonstrates that the method predicts the causes of 73.4% of the non-excessive laytimes of vessels, thereby correctly modelling 60.7% of the vessels-of-call. Following a recent deepening of the access channel, cascading waiting times due to tidal restrictions were found to be limited. Nonetheless, the importance of our approach is demonstrated by testing alternative maintained bed level designs, revealing the method's potential to support rational decision-making in coastal zones. [ABSTRACT FROM AUTHOR]

The paper describes the contracting and logistics conditions contributing to the level of anchorage in the grain, coal and fertiliser export trades of Vancouver. Increases in the level of anchorage in these trades have created economic, environmental and governance issues. Comparison of the logistics structures and practices in these commodity trades gives insights into the reasons for different levels of anchorage. Conditions in and data from the port of Vancouver are used to simulate conditions in the grain trade and to demonstrate the critical importance of the variability of ship loading times to levels of anchorage. The incidence of the costs of anchorage is examined. The terms in voyage charterparties used in the grain trade are found to inhibit efficient use of vessel time. [ABSTRACT FROM AUTHOR]

An efficient treatment plan using a temporary anchorage device should be built following the principle of reducing the number of tads to obtain a multiple biomechanical advantage. The following case report concerns the Biga system, a strategy that supports orthodontists during class II corrections and vertical control through treatment. A 12-year-old girl with a high angle of skeletal class II was selected. A novel biomechanical strategy was effectively applied using two tads on the upper arch to obtain sequential distalization of the upper teeth and to correct the lower arch spee curve using third-class elastics. Eventually, on the same tads, a double cantilever was applied to control the overbite and intrusion during incisors' retraction. The Biga system is an easy biomechanical strategy that ensures the three-dimensional control of treatment mechanics in class II patients. [ABSTRACT FROM AUTHOR]

Shape memory alloys (SMAs) show great potential in self-centering structures because of their appealing superelastic feature and good energy dissipation capability. The mechanical properties of SMA bars have been extensively studied over the past decades. However, the characteristics of smooth surface and poor machinability of the SMA bars, especially the widely used nickel–titanium SMAs, bring challenges to the anchorage systems in practical applications. This existing limitation is especially prominent for SMA bars designed to be used at the critical deformation locations of structural members or in seismic devices experiencing extreme working conditions. For this reason, this paper develops a novel hybrid threaded-swaged anchorage system to overcome the limitations of the current SMA mechanical splices. The uniaxial behavior of the threaded-swaged anchorage systems under different loading conditions was investigated experimentally with emphasis on the seismic application-oriented responses. Furthermore, the influence of eccentricity on the anchorage system was also considered to evaluate the SMA bars with large end rotation induced by the rocking behavior of the self-centering structures during earthquake shaking. Test results reveal that the performance of the proposed anchorage system is satisfactory with stable behavior under different loading conditions, which can provide a promising anchorage solution for SMA bars used in seismic resilient design. Moreover, a practical design method for this anchorage system is proposed for implementation in seismic applications. [ABSTRACT FROM AUTHOR]

The article discusses the Pterygoid Anchorage Technique, a method used in orthodontics for molar distalization. It involves inserting temporary anchorage devices (TADs) in the pterygoid region to provide better anchorage. The article presents a case report of a patient who underwent this treatment, resulting in the correction of an open bite and a stable occlusion. It also discusses the challenges and risks associated with the technique, such as anatomical variation and potential complications during TAD insertion. The article concludes by mentioning the potential benefits of using pterygoid miniscrews in orthodontic treatment. [Extracted from the article]

This article explores the use of lower third molars as anchor teeth in orthodontic treatment for Class III malocclusion. It presents a case study where fully erupted lower third molars were utilized as anchor teeth, eliminating the need for mini-implants. The treatment plan involved lingual fixed appliances and Class III elastics, resulting in successful correction of the malocclusion. The study suggests that using lower third molars as anchorage can be a viable option for patients who will eventually have their third molars extracted. [Extracted from the article]

The stress response behaviors of steel wires at the anchorage part of bridge cables under tension and bending coupling loads play a predominant role in determining their fatigue life and failure modes. The inherent complexity of the spiral geometry and the large diameter of actual bridge cables made the stress response behaviors of steel wires at the anchorage part unclear up to now. An analytical method was proposed for spiral steel wires at the anchorage part of semiparallel steel wire cables under tension and bending coupling loads. The corresponding refined numerical modeling method was also developed for studying the local anchorage part. Both the analytical formulation and numerical model agree well with the related experimental results in the literature. The presented analytical and numerical methods are thereby efficient and accurate to simulate bridge cables under tension and bending coupling loads. The critical slip curvature of steel wires increases linearly with the tensile strain of the bridge cable. The axial stresses of the steel wires of the bridge cable at a given longitudinal location display a linear relation with the angular change at the anchorage end. For steel wires located at the guide deviator part of the bridge cable, the axial stress behavior differs between the stick and slip states. It changes to a chord curve in the longitudinal direction in the stick state, while it follows an exponential function with respect to the polar angle in the slip state. The axial stress range of the outermost steel wire of the bridge cable increases linearly with the harmonic tension load range and the bending load range, separately. Regarding the phase difference between harmonic tension and bending coupling loads, a phase difference of 0 represents the most unfavorable combination for the bridge cable. By contrast, when the phase difference falls between 0 and π/2, the two harmonic loads tend to mutually inhibit each other's effects on the cable's behavior. [ABSTRACT FROM AUTHOR]

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The roof of a large-span broken rock mass is supported by prestressed anchorage, which can maintain the stability of the roadway roof to the greatest extent. Therefore, it is of great significance to study the supporting mechanism and supporting effect of prestressed anchorage on the roof of large-span broken rock mass for ensuring the long-term stability of large-span underground engineering and open-pit large-section tunnel engineering under broken rock mass. The strength change of anchorage body after anchorage is analyzed and the pre-stressed anchorage support mechanism of the roof of large-span broken rock mass is analyzed. Taking the support problem of large-span roadway in grade IV broken rock mass of Jinchanghe Polymetallic Mine as the engineering background, a numerical model is established for its support mode. The layout of structural unit Cable in FLAC3D software, the key part of numerical model establishment's analyzed. A new three-stage layout method is designed. The bolt and anchor cable are divided into pre-tightening section, free section, and anchorage section at FLAC3D software level, and their specified parameters are given for numerical calculation. Three groups of numerical simulation schemes with different support methods are established to prove the effect of prestressed anchorage support. The results show that the tensile stress of the roof in the support area is less than the tensile strength of the broken rock mass roof. Compared with the ordinary non-prestressed support design scheme, the plastic zone volume decreases by 61. 95%, and the vertical settlement of the roof in the Z direction decreases by 83. 90 %. The surrounding rock in the prestressed anchorage range is effectively controlled, and the safety of the stope roof is guaranteed. [ABSTRACT FROM AUTHOR]

The employment of the maritime medium by Southern Levantine societies is examined here through its engagement with coastline facilitation and the building of artificial harbors where natural bays are insufficient or non-existent. The development and availability of technologies and methods are surveyed and analyzed vis-à-vis local choices made to adopt or to reject mediating tools such as jetties, quays, and breakwaters. The article discusses technological and conceptual innovations against the background of long-term practices, essentially in favor of natural features. Despite the early adoption of emerging technologies by such exemplars as Iron Age Atlit, Hellenistic Akko-Ptolemaïs, or Roman Caesarea, the rest of the Southern Levant did not join in, and Caesarea, Akko-Ptolemaïs, and Atlit fell short of maintaining their facilities in the long term. The solution for ships was found instead in natural anchorages and, much more dominantly, in the beaching of smaller vessels and offshore anchoring of larger ones. [ABSTRACT FROM AUTHOR]