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Advancements in industry and increased energy demands have led to the construction of onshore and offshore platforms. The stability of these platforms is a major challenge for geotechnical engineers. Expandable anchors have recently been proposed to address this issue. Researchers have investigated the bearing capacity of anchors with different shapes and plate numbers using experimental and numerical methods. The use of a suitable method for numerical modeling of expandable anchors is necessary to determine their performance. The current study evaluated the bearing capacity of multi-plate anchors using the coupled Eulerian-Lagrangian, discrete element, and finite element methods and compares their results. The effect of an increase in the number of plates (to three), the distance between plates, the plate shape (square or circular), and the soil density (80% or 60%) on the bearing capacity of the anchors was determined. The results showed that the Eulerian model was in very good agreement with the experimental results and that the square anchor exhibited a higher bearing capacity than the circular anchor. An equation is proposed for the calculation of the bearing capacity of expandable anchors. [ABSTRACT FROM AUTHOR]

The conventional Mohr–Coulomb (M-C) failure criterion is commonly used in existing studies to determine the ultimate pullout capacity of plate anchors buried in cohesive-frictional soils. However, this criterion overestimates the tensile strength of these soils by assuming a linear failure envelope (in both compression and tensile regimes) within the normal-shear stress space. In this study, the ultimate pullout capacity of horizontally buried plate anchors in cohesive-frictional soils was determined, accounting for the effect of tensile strength cutoff. The study proposed a series of semianalytical solutions utilizing the kinematic horizontal slice approach and investigated the ultimate pullout capacity of four different anchor shapes, including circular, square, rectangular, and strip anchors. The impact of nonassociated flow rule on the results was also examined. It has been observed that the results obtained using the M-C failure criterion with a tension cutoff are significantly lower than those obtained using the conventional M-C failure criterion. The difference between both results increases as soil cohesive strength increases and anchor burial depth decreases. These findings clearly demonstrate that eliminating tensile strength from the strength envelope leads to a more conservative estimate of plate anchor pullout capacity. The study emphasizes changes in anchor failure surfaces for various parameter combinations and provides results that are consistent with specific solutions reported in the literature. Practical Applications: The study investigates using plate anchors to enhance the stability of both onshore and offshore structures, including transmission towers, guyed masts, chimneys, and mooring platforms. These structures often encounter significant vertical pullout forces. The research establishes a theoretical framework for calculating the ultimate vertical pullout capacity of plate anchors with various shapes (strip, rectangular, and circular) when buried in cohesive-frictional soils. A crucial aspect of this analysis involves incorporating the specified/limited value of tensile strength in cohesive-frictional soils when assessing the ultimate pullout capacity of plate anchors. This consideration is vital for ensuring a safe and conservative design, especially for structures subject to uplift forces. The findings provide valuable insights for engineers and practitioners, offering a reliable method to optimize the usage of plate anchors in the design of pullout-resistant structures. [ABSTRACT FROM AUTHOR]

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]

Unstable Zn interface with serious detrimental parasitic side‐reactions and uncontrollable Zn dendrites severely plagues the practical application of aqueous zinc‐ion batteries. The interface stability was closely related to the electrolyte configuration and Zn2+ depositional behavior. In this work, a unique Zn‐ion anchoring strategy is originally proposed to manipulate the coordination structure of solvated Zn‐ions and guide the Zn‐ion depositional behavior. Specifically, the amphoteric charged ion additives (denoted as DM), which act as zinc‐ion anchors, can tightly absorb on the Zn surface to guide the uniform zinc‐ion distribution by using its positively charged −NR4+ groups. While the negatively charged −SO3− groups of DM on the other hand, reduces the active water molecules within solvation sheaths of Zn‐ions. Benefiting from the special synergistic effect, Zn metal exhibits highly ordered and compact (002) Zn deposition and negligible side‐reactions. As a result, the advanced Zn||Zn symmetric cell delivers extraordinarily 7000 hours long lifespan (0.25 mA cm−2, 0.25 mAh cm−2). Additionally, based on this strategy, the NH4V4O10||Zn pouch‐cell with low negative/positive capacity ratio (N/P ratio=2.98) maintains 80.4 % capacity retention for 180 cycles. A more practical 4 cm*4 cm sized pouch‐cell could be steadily cycled in a high output capacity of 37.0 mAh over 50 cycles. [ABSTRACT FROM AUTHOR]

Unstable Zn interface with serious detrimental parasitic side‐reactions and uncontrollable Zn dendrites severely plagues the practical application of aqueous zinc‐ion batteries. The interface stability was closely related to the electrolyte configuration and Zn2+ depositional behavior. In this work, a unique Zn‐ion anchoring strategy is originally proposed to manipulate the coordination structure of solvated Zn‐ions and guide the Zn‐ion depositional behavior. Specifically, the amphoteric charged ion additives (denoted as DM), which act as zinc‐ion anchors, can tightly absorb on the Zn surface to guide the uniform zinc‐ion distribution by using its positively charged −NR4+ groups. While the negatively charged −SO3− groups of DM on the other hand, reduces the active water molecules within solvation sheaths of Zn‐ions. Benefiting from the special synergistic effect, Zn metal exhibits highly ordered and compact (002) Zn deposition and negligible side‐reactions. As a result, the advanced Zn||Zn symmetric cell delivers extraordinarily 7000 hours long lifespan (0.25 mA cm−2, 0.25 mAh cm−2). Additionally, based on this strategy, the NH4V4O10||Zn pouch‐cell with low negative/positive capacity ratio (N/P ratio=2.98) maintains 80.4 % capacity retention for 180 cycles. A more practical 4 cm*4 cm sized pouch‐cell could be steadily cycled in a high output capacity of 37.0 mAh over 50 cycles. [ABSTRACT FROM AUTHOR]

The increasing demand for deep excavations in construction projects emphasizes the necessity of robust support structures to ensure safety and stability. Support structures are critical in stabilizing excavation pits, with a primary focus on enhancing their bearing capacity. This paper employs finite element modeling techniques to conduct a numerical analysis of nails and helical anchors' bearing capacity. To reinforce the stability of pit walls, selecting an appropriate method for guard structure construction is imperative. The chosen method should efficiently redistribute forces induced by soil mass weight, displacements, and potential loads in the pit vicinity to the ground. Various techniques, including trusses, piles, cross-bracing systems, nailing, and anchorage systems, are utilized for this purpose. The study evaluates numerical models for two guard structure configurations: nailing systems and helical anchorage. It examines the impact of parameters such as displacement, helical helix count, helix diameter variations, and the integration of nailing systems with helices. Comparative analyses are conducted, including displacement comparisons between different nailing systems and helical anchor systems, along with laboratory-sampled data. The research yields significant insights, with a notable finding highlighting the superior performance of helical bracings compared to nailing systems. The conclusions drawn from this study provide specific outcomes that contribute valuable knowledge to the field of deep excavation support structures, guiding future design and implementation practices. [ABSTRACT FROM AUTHOR]

Previous plasticity models for predicting anchor kinematics under eccentric loading in clay are mostly rigid plastic. They may produce inaccurate outcomes in some conditions. This paper presents an elastoplastic model to address this issue. Closed-form solutions for anchor velocities are derived considering two types of boundary conditions: the padeye (1) fastened to a mooring chain, with the chain behavior modeled; or (2) hinged to a rigid rod. Compared with previous methods, the proposed method more realistically captures the soil behavior while avoiding complicated iterative procedures for solving anchor velocities, thus enabling anchor trajectories to be accurately and efficiently obtained by simple time integration. A series of 3D large deformation finite element analyses are conducted to study the anchor behaviors under different eccentric loading, and the proposed model is used to reproduce these simulations. Their results are compared for validation, with good agreements achieved. These results indicate that anchors under eccentric loading will ultimately translate along a fixed direction with constant soil reaction forces. Analytical solutions for this ultimate state are given based on the proposed method. Particularly, the ultimate resultant soil reaction force is demonstrated always passing through the anchor center. This is an assumption in a previous literature but is found to be a consequence of the proposed anchor constitutive relations. [ABSTRACT FROM AUTHOR]

Low water levels of the Sea of Galilee (Lake Kinneret) in recent decades due to droughts and anthropogenic factors have exposed large portions of the lakebed. Archaeological surveys of the newly exposed areas yielded prehistoric sites, harbours, anchorages, shipwrecks, cargoes and shoreline installations, attesting to changing maritime activity on the lake through time. The different assemblages are presented and discussed within the context of the lake's highly specific physical and climatic settings. Scarcity of shelters, onshore winds and unpredictable lake-level changes influenced human activity, as reflected in the archaeological records. Collectively, the finds represent the history of maritime activity on the Sea of Galilee. [ABSTRACT FROM AUTHOR]

As ground anchors are widely used to stabilize various structures, load distributive compression anchor (LDCA) is gaining popularity owing to their high load-bearing capacity and ease of removing strands. Unlike conventional anchors, an LDCA consists of multiple anchor bodies, thus allowing the distribution of the load among them. In addition, interference effects that differentiate the behavior of LDCA from that of single compression anchor are induced. These effects must be considered when designing an LDCA; however, the lack of research on its supporting mechanism has led to LCDA design being based on conventional criteria and experience. Furthermore, existing studies have not focused on the behavior of LDCA in soil, which is more vulnerable than in rock. This study proposes a physical model test that evaluates the load transfer mechanism of an LDCA. A series of pull-out tests is performed on an LDCA installed in residual soil to investigate the behavior of the LDCA under various conditions, by varying parameters such as the total anchor length, number and spacing of anchor bodies, and loading conditions. The test results show that the movement of the upper anchor body causes a tensile load on the grout and additional grout–soil shear stress on the lower anchor body, which reduces the ultimate bearing capacity of the LDCA. Moreover, the test results reveal that the interference effect between anchor bodies increases as the spacing decreases, thus resulting in a greater reduction in the ultimate bearing capacity. The findings of this study are anticipated to develop the basis for the design and application of LDCA. [ABSTRACT FROM AUTHOR]

The existing research on anchor foundations has predominantly focused on their axial load-carrying capacity, disregarding their resistance to the combined uplift and lateral forces during operation. To address this gap, the present study employs a three-dimensional finite-difference analysis to examine the behavior of horizontal anchor foundations buried in sand under the influence of uplift and lateral loads. The novelty of this work lies in the application of combined loading on the shaft head and the subsequent evaluation of both vertical and horizontal displacements of the foundation. The results reveal that the displacements are notably more significant in the horizontal direction. Furthermore, the paper presents a detailed analysis of the foundation's failure mechanisms under various combinations of vertical and horizontal forces. It is observed that pure vertical forces induce an uplift shear failure, whereas pure horizontal forces lead to a rotational failure. Based on the results, a failure envelope in the V:H loading plane is proposed for the horizontal anchor foundation subjected to oblique loads. [ABSTRACT FROM AUTHOR]

Prestressed anchor cables are commonly utilized to reinforce slopes in earthquake-prone zones. The existing upper bound limit analyses of seismic slopes reinforced with prestressed anchor cables have the following limitations: (1) neglecting variable seismic excitations; (2) ignoring the three-dimensional spatial layout of cables because of using the plane-strain analysis. In this study, the time-space effects of seismic waves are analytically described by sin-cos functions incorporating wave amplification or soil damping. Based on the upper bound of plastic theory and a three-dimensional discretized failure mechanism, internal energy dissipation rate and work rates contributed by gravitational forces, variable seismic excitations, and prestressed anchor cables are computed. An energy-based function of dynamic factors of safety (DFS) is established, followed by a global optimization to identify the critical harmonic pattern of DFS. The accuracy is checked by numerical simulations where the seismic stability of an engineering slope adjacent to Yu-Huai railway is evaluated. Comparisons also show that the conventional simplified method not only cannot reflect the spatial layout of cables but also overestimate the mechanical contribution of cables. Finally, the dominant effects of the layout of cables, soil properties as well as physical parameters of seismic waves on the DFS and the critical failure mechanism are discussed. A method to evaluate the stability of seismic cable-reinforced slopes A kinematical admissible 3D failure mechanism of cable-reinforced slopes is generated Critical harmonic pattern of safety factors is explicitly obtained. Effect of cable layout, dynamic parameters and soil properties are discussed. [ABSTRACT FROM AUTHOR]

In the process of lower coal roadway support under double gobs in close coal seams, there are problems such as the whole destruction of the lower coal seam and the intermediate strata, the thin roof of the lower coal roadway with the smaller support space, the upper rock of the lower coal roadway without anchor bearing layer, the roof falling, the anchor cable offing, and so on. On the basis of the engineering background of No. 11103 haulage roadway in Fenxi coal mine, the research methods of theoretical modeling analysis, numerical simulation analysis and field engineering test are comprehensively adopted. In this paper, the layout of the roadway with floor insertion in the lower coal seam, the distribution characteristics of surrounding rock deviatoric stress, the control principle of broken surrounding rock and the coupling support method of shed–cable–prop are systematically studied. The study shows that many measures are needed to ensure the stability of the surrounding rock in the strong mining roadway of the lower coal seam. The lower coal seam roadway section was modified from the original rectangular section to adopt an arched section to counteract the broken roof. The staggered position of the lower coal seam roadway layout was modified from the original coal roadway position to a coal–rock roadway, so as to avoid the area of high deviatoric stress in the coal pillar and the area of crushed coal body, and to leave an effective support space for the roof. The support scheme of the lower coal seam roadway was improved to use anchor cable and single prop to support the weak section of U‐type steel shed with local coupling, and realize unequal force coupling by adjusting the size of the force at different coupling points. In the field monitoring the deformation of the roadway is small, and the support effect is good. [ABSTRACT FROM AUTHOR]

Possible discontinuities in the subsurface have a major impact on the load‐bearing behavior of post‐installed fastenings. For concrete, the behavior of post‐installed anchors and thus their design can be clearly addressed as concrete is assumed as a homogeneous fastening substrate. This is valid except, for example, in the area of building joints and at joints of precast concrete elements, where the formation of structural joints inevitably occurs and which basically correspond to a separation surface. In contrast, rock mass is characterized by the rock type, but is generally also significantly influenced by its discontinuities. These play a decisive role concerning rock mass stability and show a great impact on the load‐bearing capacity of rock, especially for fasteners with a shallow embedment depth. It is to be assumed that the same also applies to separating surfaces in concrete. Furthermore, the question arises as to the non‐destructive preliminary detectability of such weak zones. For carrying out a comparative study under controlled conditions, artificial interfaces of different geometries were generated in concrete in laboratory tests by inserting PTFE layers at different positions of the test member. Pull‐out tests of post‐installed fastening systems were carried out in their vicinity to determine the load transfer as well as the failure mode. It could be shown that discontinuities have a negative effect on pull‐out loads not only in the rock mass, but also in concrete. However, detection of these by means of a rebound hammer was only possible in the rock mass. [ABSTRACT FROM AUTHOR]

The success rate of spinal fusion surgery is mainly determined by the fixation strength of the spinal bone anchors. This study explores the use of an L-shaped spinal bone anchor that is intended to establish a macro-shape lock with the posterior cortical layer of the vertebral body, thereby increasing the pull-out resistance of the anchor. The performance of this L-shaped anchor was evaluated in lumbar vertebra phantoms (L1-L5) across four distinct perpendicular orientations (lateral, medial, superior, and inferior). During the pull-out experiments, the pull-out force, and the displacement of the anchor with respect to the vertebra was measured which allowed the determination of the maximal pull-out force (mean: 123 N ± 25 N) and the initial pull-out force, the initial force required to start motion of the anchor (mean: 23 N ± 16 N). Notably, the maximum pull-out force was observed when the anchor engaged the cortical bone layer. The results demonstrate the potential benefits of utilising a spinal bone anchor featuring a macro-shape lock with the cortical bone layer to increase the pull-out force. Combining the macro shape-lock fixation method with the conventional pedicle screw shows the potential to significantly enhance the fixation strength of spinal bone anchors. [ABSTRACT FROM AUTHOR]

We investigate a deep foundation pit for urban substation construction in Chengdu, China. The pit was excavated in a sandy gravel layer and has a depth of 24.6 m. Detailed field surveys and monitoring were carried out to investigate the deformation characteristics of the foundation pit and its supporting structure related to excavation. Flac3D software was used to analyze the influence of pile anchor design parameters, including pile diameters, pile spacing, anchor cable prestress, anchor angle, and the number of rows of anchor cables, on deformation of the deep foundation pit. The results showed the pile diameter was the most critical influencing factor for pile deformation. The influences of anchor cable prestress and anchor angle on the horizontal displacement of the pile were inferior to the influence of the pile diameter and the number of anchor cable rows. The results reported in this paper provide guidance for the optimal design of foundation pits in settings with similar geological conditions. [ABSTRACT FROM AUTHOR]

The fish anchor is an economically viable offshore foundation engineering technology that has been proposed in recent years. By fish anchor, we mean a fish-shaped dynamically installed anchor that can penetrate into the seabed through water by its own weight. However, the existing research studies seldom consider the hydrodynamic characteristics of its free fall installation, resulting in uncertainties regarding its underwater installation characteristics. Therefore, based on OpenFOAM, this study first investigated the directional stability of fish anchors during its underwater falling process through the static model analysis method and dynamic model analysis method. The findings indicated that the directional stability of fish anchors was insufficient, rendering them suitable only for release and installation at low heights (i.e., less than 4.2 times the anchor length) without marine environmental loads. Furthermore, the anchor inclination angle during installation is significant, thereby impacting its penetration depth and pull-out capacity in the seabed. To solve this problem, the concept of an innovative booster-assisted fish anchor is proposed, which can significantly enhance the directional stability of conventional fish anchors. Results show that the maximum installation height of the new booster-assisted fish anchor is increased by 2.4 times compared to the original design, thereby enhancing both the penetration speed and uplift capacity. Based on the findings, recommended installation and construction conditions are provided. Finally, a predictive formula for the installation height and verticality of the new booster-assisted fish anchor under current action is presented to offer guidance for engineering applications. [ABSTRACT FROM AUTHOR]

The Fosbury flop tear (FFT) has recently been described as a rotator cuff tear that has flipped upon itself and adhered medially. FFT is known to have a high retear rate after arthroscopic rotator cuff repair. The cause of the high postoperative retear rate after arthroscopic rotator cuff repair is believed to be due to the inability to achieve anatomical reduction because of difficulties in reducing the torn tendon stump. Arthroscopic rotator cuff repairs using the triple-row technique may allow better anatomical reduction of the cuff tear when compared with the suture-bridge technique. We compared the clinical outcomes and cuff integrity of the triple-row and suture-bridge techniques in arthroscopic rotator cuff repair for FFT. Patients with small-to-medium sized cuff tears of the supraspinatus tendon alone who were diagnosed with FFT, underwent arthroscopic rotator cuff repair, and had 2 or more years of follow-up were included. A total of 34 shoulders underwent the triple-row technique and 22 shoulders underwent the suture-bridge technique. The following were compared between the two techniques: patient background, operation time, number of anchors used during the operation, Japanese Orthopedic Association (JOA) score, active range of motion, and retear rate. No significant difference in patient background was found between the two techniques. Although active range of motion was significantly improved compared with preoperative scores, no significant difference was observed between techniques. The triple-row technique demonstrated a significantly higher 24-month postoperative JOA score, significantly shorter surgery time, significantly lower retear rate, and significantly larger number of anchors used during the operation. The triple-row technique was an effective method compared with the suture-bridge technique in cases with FFT. [ABSTRACT FROM AUTHOR]

Development of a novel compact yielding anchor cable aims to address the demand for anchorage support in deep rock masses that experience significant deformation. This innovative cable utilizes the combined energy release principles of the expansion tube and spiral transmission. The yielding device primarily consists of an external yielding sleeve (threaded tube) and an internal yielding body. The internal yielding body is created by embedding a cone within the steel strand of the anchor cable. Through extrusion slip and cooperative fastening rotation, the yielding mechanism achieves high-strength constant-resistance yielding support within a small aperture. A thorough analysis of the yielding mechanical behavior has led to the establishment of a theoretical calculation model for the yielding force. This was followed by experimental investigations into the mechanical characteristics. The key findings are as follows: (1) the length and the large end diameter of the yielding body are crucial parameters that influence the yielding performance, with the length having a more significant impact; (2) the yielding force ranges from 121.4 to 170.4 kN, demonstrating high-strength yielding within a compact design; (3) the theoretical values of the yielding force show a deviation ranging from − 17.3 to 13.4% when compared to the measured value. This indicates an acceptable agreement between the calculation model and the experimental results, affirming the credibility of the yielding mechanical behavior analysis; (4) the yielding force exhibits periodic fluctuation within the range of 120 ~ 170 kN during stable yielding, while the energy release rate of the yielding process is 0.191 kJ/mm. For example, when considering a 5 m yielding cable with a 250 mm yielding length, the released energy prior to material yield increases from 14.75 to 62.50 kJ (a rise of 323.7%), and the maximum release energy increases from 90.25 to 138.00 kJ (a rise of 52.9%). This highlights the effectiveness of enhancing the energy release capability, especially prior to the material yield of the cable shaft. Highlights: A novel compact yielding anchor cable, incorporating the combined energy release principles of the expansion tube and spiral transmission, was developed to provide effective yielding support for substantial deformations in high-stress conditions. The theoretical analysis model of yielding behavior, which accounts for extrusion slip and cooperative fastening rotation, accurately describes the yielding force, underscoring the reliability of the yielding mechanical behavior analysis. The compact yielding design significantly enhances the energy release capability, particularly before the material yield of the cable shaft, thereby reducing the potential risk of anchor cable failure in the face of significant deformation. [ABSTRACT FROM AUTHOR]

Plate anchors have great advantages that are useful in deep or ultradeep water mooring systems. The keying behaviors have a deep effect on the embedment loss and pullout capacity of strip plate anchors. In this paper, the effect of soil remolding on the keying behaviors of strip plate anchors is studied by large deformation finite-element (LDFE) analysis. First, the LDFE results are compared with centrifugal test results, theoretical solutions, and LDFE data from previous literature, showing good agreement. Then, a series of LDFE cases is studied to investigate the effects of the padeye offset, load eccentricity, soil sensitivity, and initial embedment depth on the embedment loss and pullout capacity of plate anchors during the keying process. The LDFE results show that different load eccentricity corresponds to different soil failure mechanisms, and both padeye offset and soil remolding will reduce the pullout capacity of plate anchors. Finally, an equivalent soil strength is introduced considering rate effect and soil remolding of clay. A combined factor and an equivalent ultimate pullout capacity are used to estimate the ultimate embedment loss and pullout capacity of strip plate anchors in uniform clay, respectively. [ABSTRACT FROM AUTHOR]

This study proposed a modified lift-off test that enables evaluation of the anchoring condition (anchored capacity or creep ratio) during the investigation of the residual anchor load and facilitates the restressing of anchors. To verify the applicability of the proposed measure in practice, a case study of the rehabilitated landslide slope of the T16 support tower of the Taipei Maokong Gondola System was conducted, a two-stage procedure that simultaneously facilitated the investigation and rehabilitation of an anchored slope with load loss. Results of an investigation of the residual load acting on 619 anchors indicated that the average load loss of the anchors was approximately 36% compared with the design load. In conventional design, approximately 223 extra anchors must be installed in the study area. However, the corresponding number in the proposed measure is about one-fifth the number of anchors required in the conventional approach. This paper emphasizes the merit of using the modified lift-off test in reducing construction time and construction costs in slope rehabilitation. Furthermore, the proposed rehabilitation measure adopted in this study did not involve adding many concrete structures to the original anchored slope. Thus, these measures are environmentally friendly and contribute to sustainable development. [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]

This paper presents a comprehensive three-dimensional numerical investigation of horizontal square anchors embedded in geogrid-reinforced sand. Prior experimental studies have demonstrated notable enhancements in anchor uplift capacity when placed below geogrid reinforcement in soil. However, these results are limited to small anchor plates tested in laboratory conditions with over-reinforced sand. In contrast, this study focuses on large field-scale anchors and explores the influence of anchor width, embedment depth, reinforcement size, stiffness, and tensile strength on uplift capacity. The findings reveal that the optimal size for geogrid reinforcement is three times the anchor width. A diminishing improvement in uplift capacity with increasing anchor width was observed. Additionally, deeper anchor embedment reduces the uplift capacity improvement in geogrid-reinforced sand. The geogrid reinforcement is found to be more efficient in the case of shallow anchors placed in loose sand. The major contribution of this paper lies in the response analysis of large anchors and providing a better understanding of the uplift mechanism in geogrid-reinforced sand. • This paper presents a three-dimensional numerical investigation of large field-scale horizontal square anchors embedded in geogrid-reinforced sand. • The findings reveal that the optimal size for geogrid reinforcement is three times the anchor width (B) in contrary to the 5B value reported in the previous literature. • A diminishing improvement in uplift capacity with increasing anchor width was observed. • Deeper anchor embedment reduced the uplift capacity improvement in geogrid-reinforced sand. • The geogrid reinforcement is found to be more efficient in the case of shallow anchors. [ABSTRACT FROM AUTHOR]

In order to solve the problems of excessive weight and unreasonable structure of anchor machine parts caused by traditional design methods, a lightweight optimization method was proposed based on pre-stressed modal analysis. The design variables were determined, and the parameterized model was established by using ANSYS Workbench. Under ultimate load conditions, the strength of wall frame board and lower box bodies was simulated and calculated. Through modal analysis, the discretized natural frequencies under different design variables could be obtained. The multi-objective genetic algorithm and sequence quadratic programming were respectively used to calculate the lightweight analysis model. The results showed that the weight of the supporting components in ship anchor can be reduced by more than 5 % without reducing strength and equivalent stiffness. [ABSTRACT FROM AUTHOR]

In this paper, using CsMA2Sn2I7 as an example, first‐principles calculations are performed to thoroughly investigate the crystal structures, electronic properties, and optical properties of 11 representative anchoring group/low‐dimensional hybrid perovskite systems. The results show that the addition of benzene, 4‐iodoaniline, aniline, and benzenethiol anchoring groups causes a blueshift phenomenon in the absorption spectra of CsMA2Sn2I7 perovskite. Furthermore, the involvement of the benzoic acid anchoring group has a minimal effect on the absorption spectra of the CsMA2Sn2I7 hybrid perovskites, which show better absorption intensity only in the ultraviolet. The addition of other anchoring groups leads to varying degrees of redshift in the absorption spectra of CsMA2Sn2I7 perovskite, which not only enhances absorption intensity but also lends to the improvement of the absorption efficiency in the visible range. In addition, the bandgap can be tuned by applying biaxial strain, which further effectively modulates the absorption intensity of the adsorption systems in different optical bands. Therefore, the selection of suitable anchoring groups has great potential for modulating the photovoltaic performance of organic–inorganic hybrid perovskites, which is helpful for the application of organic–inorganic perovskites in photovoltaics. [ABSTRACT FROM AUTHOR]

A critical function of polymeric matrices in biological systems is to exert selective control over the transport of thousands of nanoparticulate species. Utilizing "third-party" molecular anchors to crosslink nanoparticulates to the matrix is an effective strategy, and a trapped nanoparticulate formed a desired complex MAP that is necessary to keep the nanoparticulate immobilized at any given time. In this paper, the global solution and stability of a parabolic–ordinary-parabolic haptotaxis system to complex MAP are studied. First, the existence of a local classical solution to system (4) has been observed using fixed point argument and parabolic Schauder estimates. Furthermore, some a priori estimates that can raise the regularity estimate of the solution for the relatively complicated first equation of system (3) from L ρ to L 2 ρ ( ρ ≥ 1 ) are given; then, the local classic solution can thus extend to the global classic solution when the space dimension N ≤ 3 . Lastly, by using various analytical methods, a threshold value ξ 00 (ξ 00 < 0) is found, such that positive constant steady state (u ∗ , v ∗ , w ∗) becomes unstable when ξ < ξ 00 . Our results show that the haptotaxis plays a crucial role in determining the stability to the model (3), that is, it can have a destabilizing effect. [ABSTRACT FROM AUTHOR]

Based on the three‐dimensional limit equilibrium method with modifying normal stress over the slip surface, this study presents a theoretical solution for the anchoring force of three‐dimensional slopes and proposes a new optimization strategy for anchor force distribution. The method employed the Boussinesq solution from the field of elasticity. It led to the derivation of an equilibrium equation set, which incorporated the anchoring force increment. As a result, the approach yielded a more accurate theoretical value for a three‐dimensional anchoring force. In practical engineering applications, the prestress of anchor cables is often uniformly set, which may lead to discrepancies in the anchoring force requirements at different locations on the slope, potentially resulting in resource waste. The research introduces a linear programming approach to optimize resource allocation, aiming to minimize the total anchoring force under fixed anchor cable quantities, installation angles, and locations. Nevertheless, the results from the Simplex Method could lead to an overly concentrated distribution of anchoring force. Therefore, the study further employs the normal distribution theory to reallocate anchoring forces, thus achieving a more reasonable distribution. The proposed method has been validated through three example studies and a practical engineering case study, resulting in significant reductions in the total anchoring force following optimization. Moreover, such an approach allows for optimized handling of the anchoring force for each anchor cable. The work provides a new perspective and tool for practical engineering applications. [ABSTRACT FROM AUTHOR]

The article discusses a study examining gender inequality in relation to the representation of female television news anchors in Portugal. Topics discussed include gender stereotypes in broadcast news, the subrepresentation of women anchors in relation to the glass ceiling theory, and the gender imbalance among female and male news anchors in the four main television channels.

Pull-out strength tests conducted on screw anchors in uncracked concrete substrates of the C25/30 class are presented in this article. The destructive force for anchor–concrete fasting was tested, and in the next step, the average pull-out strengths of screw anchors in concrete substrates with and without the addition of steel fiber were determined. Currently, the pull-out strengths of anchors in fiber-reinforced concrete substrates are defined as for unreinforced concrete substrates. Therefore, pull-out tests were performed for screw anchors in fiber-reinforced concrete substrates. Fiber contents of 10, 20, 30, and 50 kg/m3 were used. An increase in the load capacity of screw anchors in a fiber-reinforced concrete substrate was demonstrated in a pull-out test compared to base samples without fibers. The coefficient related to the actual fastening behavior of a screw anchor in the fiber-reinforced concrete substrate was determined. It was assumed that a coefficient of 13.10 should be adopted. This was the lowest value obtained for the load capacity in this study for screw anchors in a fiber-reinforced concrete substrate. [ABSTRACT FROM AUTHOR]

Background: Displaced olecranon fractures constitute a challenging problem for elbow surgeons. The purpose of this study is to evaluate the role of suture anchor fixation for treating patients with displaced olecranon fractures. Methods: A retrospective review was performed for all consecutive patients with displaced olecranon fractures treated with suture anchor fixation with at least 2 years of clinical follow-up. Surgical repair was performed acutely in all cases with nonmetallic suture anchors in a double-row configuration utilizing suture augmentation via the triceps tendon. Osseous union and perioperative complications were uniformly assessed. Results: Suture anchor fixation was performed on 17 patients with displaced olecranon fractures. Functional outcome scores were collected from 12 patients (70.6%). The mean age at the time of surgery was 65.6 years, and the mean follow-up was 5.6 years. Sixteen of 17 patients (94%) achieved osseous union in an acceptable position. No hardware-related complications or fixation failure occurred. Mean postoperative shortened disabilities of the arm, shoulder, and hand (QuickDASH) score was 3.8±6.9, and mean Oxford Elbow Score was 47.5±1.0, with nine patients (75%) achieving a perfect score. Conclusions: Suture anchor fixation of displaced olecranon fractures resulted in excellent midterm functional outcomes. Additionally, this technique resulted in high rates of osseous union without any hardware-related complications or fixation failures. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

We study the effect of perceivers' health conditions on their judgments of the well-being of target people (their judgments of the targets' day-to-day physical difficulties) based on information about the targets' health conditions. We develop a model which suggests that this effect depends on the similarity between perceivers' and targets' health: The perceiver's well-being is used as an anchor and the judgment of the target's well-being is either assimilated toward or contrasted away from this anchor, depending on the similarity between the subject's and target's health. Based on this model we derive and test the correlation-trend hypothesis which states that the higher the similarity between perceivers' and targets' conditions, the more positive the correlation between perceivers' conditions and their judgments of the targets well-being. [ABSTRACT FROM AUTHOR]

Resin distribution in a borehole is critical to the anchoring performance during resin-anchored bolt installation. The distribution characteristics of the resin may be affected by fractures in the soft and broken surrounding rock of the borehole wall. Accordingly, numerical simulations, theoretical analyses, and laboratory experiments were performed to explore the resin flow characteristics and the anchoring performance of resin-anchored bolts in soft and broken surrounding rock. The results indicate that, for resin mixing in soft and broken surrounding rock, the resin and the curing agent rapidly flow into the fractures in the borehole wall during the rotation and advancement of the bolt toward the bottom of the borehole, resulting in resin loss. The amount of resin loss increases with the fracture aperture, number of fractures, and fracture angle, continuously weakening the anchoring performance. With increasing number of fractures, the deformation of the anchoring system before reaching the maximum anchoring force gradually increases. Conversely, an anchoring system with no fractures can quickly play its bearing role and provide a high working resistance. In addition, an improving method of anchoring performance was proposed: grouting reinforcement and borehole wall repair can enhance the strength of the surrounding rock, reduce the fracture aperture and resin loss, and improve the anchoring quality. This paper provides a theoretical reference for the stability control and anchoring quality improvement of soft and broken surrounding rock. Highlights: The resin and the curing agent will flow into the fractures in the borehole wall during resin mixing process of resin-anchored bolt installation. The amount of resin loss increases with the fracture aperture, number of fractures, and fracture angle. The increase in the resin loss amount will continuously weaken the bearing capacity of an anchoring system. An improving method of anchoring performance was proposed by enhancing the surrounding rock strength and reducing the fracture aperture. [ABSTRACT FROM AUTHOR]

Offshore oil and gas exploration activities involve the installation of various subsea infrastructures on the ocean floor, often supported by shallow foundations such as anchor plates or mudmats. These foundations must be designed to withstand applied service loads along the structure lifecycle, including decommissioning loads required for subsequent removal. In this context, this work is dedicated to the evaluation of uplift bearing capacity of shallow anchors within the theoretical framework of limit analysis and its related kinematic approach. Based on the implementation of 3D failure mechanisms, rigorous upper bound estimates for the uplift force viewed as ultimate load for the material system are derived from either total or effective stress analyses. In that respect, emphasis is given to the formulation of limit analysis problem in the context of effective stresses, showing how the effect of seepage flow may be accounted for by means of driving body forces derived from the gradient of excess pore pressure distribution and how suction forces arise from pore pressure difference between upper and lower anchor surfaces. Evaluation of suction forces developed during anchor lifting is addressed by resorting to a simplified modeling applied to circular and rectangular anchors. The accuracy of the upper bound predictions derived for uplift force is assessed by comparison with available experimental data. Several numerical results are also provided to investigate the effects of relevant problem parameters on the uplift bearing capacity. [ABSTRACT FROM AUTHOR]

Electromyography (EMG) proves invaluable myoelectric manifestation in identifying neuromuscular alterations resulting from ischemic strokes, serving as a potential marker for diagnostics of gait impairments caused by ischemia. This study aims to develop an interpretable machine learning (ML) framework capable of distinguishing between the myoelectric patterns of stroke patients and those of healthy individuals through Explainable Artificial Intelligence (XAI) techniques. The research included 48 stroke patients (average age 70.6 years, 65% male) undergoing treatment at a rehabilitation center, alongside 75 healthy adults (average age 76.3 years, 32% male) as the control group. EMG signals were recorded from wearable devices positioned on the bicep femoris and lateral gastrocnemius muscles of both lower limbs during indoor ground walking in a gait laboratory. Boosting ML techniques were deployed to identify stroke-related gait impairments using EMG gait features. Furthermore, we employed XAI techniques, such as Shapley Additive Explanations (SHAP), Local Interpretable Model-Agnostic Explanations (LIME), and Anchors to interpret the role of EMG variables in the stroke-prediction models. Among the ML models assessed, the GBoost model demonstrated the highest classification performance (AUROC: 0.94) during cross-validation with the training dataset, and it also overperformed (AUROC: 0.92, accuracy: 85.26%) when evaluated using the testing EMG dataset. Through SHAP and LIME analyses, the study identified that EMG spectral features contributing to distinguishing the stroke group from the control group were associated with the right bicep femoris and lateral gastrocnemius muscles. This interpretable EMG-based stroke prediction model holds promise as an objective tool for predicting post-stroke gait impairments. Its potential application could greatly assist in managing post-stroke rehabilitation by providing reliable EMG biomarkers and address potential gait impairment in individuals recovering from ischemic stroke. [ABSTRACT FROM AUTHOR]

Outdoor Location-Based Augmented Reality (LAR) applications require precise positioning for seamless integrations of virtual content into immersive experiences. However, common solutions in outdoor LAR applications rely on traditional smartphone sensor fusion methods, such as the Global Positioning System (GPS) and compasses, which often lack the accuracy needed for precise AR content alignments. In this paper, we introduce an innovative approach to enhance LAR anchor precision in outdoor environments. We leveraged Visual Simultaneous Localization and Mapping (VSLAM) technology, in combination with innovative cloud-based methodologies, and harnessed the extensive visual reference database of Google Street View (GSV), to address the accuracy limitation problems. For the evaluation, 10 Point of Interest (POI) locations were used as anchor point coordinates in the experiments. We compared the accuracies between our approach and the common sensor fusion LAR solution comprehensively involving accuracy benchmarking and running load performance testing. The results demonstrate substantial enhancements in overall positioning accuracies compared to conventional GPS-based approaches for aligning AR anchor content in the real world. [ABSTRACT FROM AUTHOR]

As the latest development of gravity installed anchors (GIAs), the OMNI-Max anchor has drawn much attention from worldwide due to its unique behavior in the seabed. The pullout capacity of OMNI-Max anchors is a key index in engineering. However, most of the relevant studies were carried out under a quasi-static condition, which do not actually meet the installation and operation requirements. In practice, the anchor may be subjected to both long-term and short-term sharp loading during mooring. As an important environmental variable, it is essential to evaluate the effect of loading rate on the pullout capacity. Since the bearing capacity of OMNI-Max anchors is affected by many factors, it is also essential to explore systematically the coupling effects of the loading rate and other factors, including the anchor embedment depth, the anchor orientation, the bearing area, the loading angle, and the soil strength. Based on the coupled Eulerian-Lagrangian (CEL) technique, numerous analytical cases are designed and calculated by the large deformation finite element (LDFE) method. The loading rates span four orders of magnitude from the quasi-static velocity to 10 m/s (about one anchor length per second), covering a wider range in pulling out of GIAs. The end-bearing capacity factor changes remarkably with the pullout velocity for OMNI-Max anchors, and the increase can even reach more than twice of that in a quasi-static condition. As a result, a succinct explicit expression is constructed in terms of the loading rate and multiple factors, which can be effectively utilized to calculate the end-bearing capacity factor of OMNI-Max anchors in clay under complex conditions. [ABSTRACT FROM AUTHOR]

It is difficult for traditional anchoring structures to meet the tight construction period and high support effect requirements of deep foundation pit projects in soft soil areas, Therefore, a tensioning embedded composite drainage anchoring structure was proposed. By analyzing the anchoring mechanism of the new support structure, it can be concluded that the force acting on the anchor rod during the excavation process is divided into three stages: pre-tensioning stage, increasing end resistance stage and anchoring failure stage; a method for calculating the bearing capacity of new anchor rods was provided; the support effect and drainage characteristics of the new structure were simulated and analyzed by using finite element software. The results show that: the axial force distribution of the new anchor rod is different from that of the ordinary anchor rod, and there is a sharp increase in axial force at the pre-tensioned anchor head position; compared to ordinary anchor, the new anchoring structure has better support effect, which can reduce the maximum horizontal displacement of the slope by 37.2% and is more conducive to the stability of the foundation pit; the new anchoring support structure has good drainage effect and can quickly dissipate the pore water pressure near the free slope surface. [ABSTRACT FROM AUTHOR]

Prestress loss of anchor cables can cause a change in the internal force for the support structure of a foundation pit or slope, which may cause engineering accidents. The coupling effect between an anchor cable and the creep of rock and soil is the main factor that leads to the loss of prestress of the anchor cables. However, the traditional Hooke–Kelvin (H-K) viscoelastic model could not accurately predict the long-term loss of prestress. To solve this problem, based on the H-K viscoelastic model, a new H-3K viscoelastic model was proposed, consisting of two generalized Kelvin bodies connected in parallel, and its creep equation and relaxation equation were also derived. Focusing on slope engineering in Longnan City, Gansu Province, China, the prestress of anchor cables calculated by the proposed model were compared with the monitoring data. The result that the H-K creep coupling model is more accurate in predicting prestress loss of anchor cables in the initial stage, but from a long-term perspective, the H-3K creep coupling model provided a more accurate prediction. By connecting more generalized Kelvin bodies in parallel, stress shared by the elastic body can be reduced and stress loss due to anchor cable relaxation can be approximately compensated for to make the prediction results closer to the monitored values. However, when there are more than three Kelvin bodies in parallel, the model prediction results will change only slightly. Therefore, the H-3K creep coupling model is sufficient for practical engineering. [ABSTRACT FROM AUTHOR]

Aircraft skin, skeleton, and wing components contain a large number of riveted holes. There are few hole-making studies of double lug anchor nut connection 2024 aluminum alloy (Al2024) plates. To improve the quality of riveting holes on the anchor nut, two different hole-making schemes for two different sizes of holes on connection plate of the double lug anchor nut were proposed, and orthogonal experiments were conducted. The holes distributed on both sides were drilled, and the range analysis results and the optimal parameters were obtained: the spindle speed is 3000 r/min, and the feed rate is 0.04 mm/r. The coaxle hole with middle hole of nut was machined by the helical milling plan, the analysis results and the optimal parameters were obtained: the spindle speed is 3000 r/min, the feed rate is 0.08 mm/r, and the number of blade teeth is 4. Based on the obtained optimal parameters, the process sequence of first drilling and then helical milling (D + H) and first helical milling and then drilling (H + D) was proposed. In drilling, there is a significant fluctuation of force in the y-axis direction when using the process sequence of D + H. At the beginning of the helical milling experiment, the rising speed of the axial force of D + H is smoother than H + D. The deformation along the x-axis direction and the along the y-axis direction of the process sequence of D + H is 63.9 μm and 49.6 μm, which are 75.5% and 76.5% of H + D. Finally, experimental studies were carried out in the workshop. In drilling, the burr height is 77.1 μm, and hole diameter is 2.617 mm. In helical milling, the burr height is 20.7 μm, and the hole diameter is 5.023 mm. The deformation of the Al2024 is 64.3 μm. The optimal machining parameters and the process sequence of D + H can meet the technical requirements of connecting plate of the double lug anchor nut. [ABSTRACT FROM AUTHOR]

The study reported here aims to investigate the application of shape memory alloys (SMAs) in the form of strips for strengthening cracked reinforced concrete (RC) beams. The study proposes an innovative technique for prestressing RC beams by utilizing the shape recovery property of the alloy. Nine full-scale RC beams with a length of 3.75 m and a cross-section of 200 mm × 300 mm were categorized into three groups based on the steel reinforcement ratio, and tested under static loading. Three RC beams were used as control specimens and the other six were retrofitted with either one layer or two layers of SMA strips. The beams to be strengthened were exposed to an initial applied load before the installation of the SMA strip to simulate the deterioration scenario. SMA strips were retrofitted on the soffits of the deteriorated beams and activated by applying temperature from an external heat source while the temperature-deflection-strain measurements were monitored. Specimens were tested again up to failure to evaluate the strength improvement of the retrofitted specimens. Beams retrofitted with one layer of SMA experienced a deflection recovery up to 2.3 mm upon activation and an additional service load of up to 62%, whereas beams retrofitted with two layers experienced a deflection recovery up to 2.8 mm and an additional service load of up to 95%. In general, the deflection recovery was proportional to the ratio of the total reinforcement ratio after strengthening to the initial reinforcement ratio before strengthening. Therefore, tested specimens with two SMA layers experienced less improvement than specimens with one SMA layer. Finally, the experimental results were evaluated with two analytical methods: ACI method and the non-linear sectional analysis proposed by Oukaili. [ABSTRACT FROM AUTHOR]

To investigate the real anchorage performance of basalt and glass hybrid fiber reinforced plastic (FRP) anchors in external corrosive environments. In this paper, a combination of experimental studies and finite element analysis was used. By carrying out pull‐out tests of basalt and glass hybrid FRP anchors under the synergistic effect of freeze–thaw cycles and alkaline environment, the effects of factors such as hole diameter, anchorage length, and mortar strength on their anchorage performance and durability were investigated. Critical corrosion time was introduced to determine the degree of corrosion of the anchor rods. After that, it combined with numerical simulation to reveal the degradation mechanism of the anchorage performance of hybrid anchors. The results showed that the best anchorage performance of basalt/glass hybrid FRP anchors was achieved when the hole diameter was 24 mm, the anchorage length was 175 mm, and the mortar strength was 45.5 MPa. The ultimate pull‐out load was up to 122.16 kN. When the time did not exceed the critical corrosion time, the ultimate load‐carrying capacity of basalt and glass hybrid FRP anchors increased by 9.3% compared to the uncorroded environment. Beyond the critical corrosion time, the ultimate load‐carrying capacity was reduced by 23.3% and the anchorage performance was degraded. In addition, the contact interface between the anchor and the mortar is the weak area of the anchoring structure, which should be focused on in the later design of the actual project. Highlights: Basalt/glass hybrid FRP anchors have good corrosion resistance.The anchoring performance of hybrid FRP anchors under the coupled environment is studied.Hole diameter and anchoring length have more influence on the anchor performance.The concept of critical corrosion time is put forward.The failure mechanism and coupling environment influence are revealed by FES. [ABSTRACT FROM AUTHOR]

The book review discusses "Reconceptualizing schizophrenia: The phenomenology of urhomelessness" edited by Kamens, S. The book explores the role of culture in the development of schizophrenia experiences and investigates whether there is a common underlying structure to these experiences across cultures. The author, Sarah Kamens, uses diverse methods and participants to examine the concept of schizophrenia as a profound sense of vulnerability and alienation called "urhomelessness." The book offers a culturally sensitive perspective on schizophrenia and has implications for phenomenological psychopathology. The review praises Kamens' work for providing a compassionate framework that deepens understanding of individuals with schizophrenia and their experiences of alienation. [Extracted from the article]

Multi-underreamed anchors (MUAs) are widely used in areas with soft soils owing to their high ultimate capacity. To explore the bearing mechanism of MUAs in soft soil, this paper performs a model test of MUAs in silty clay and draws the following conclusions. With an increase in the underream number of MUAs, the ultimate capacity of the anchors significantly increases. The strength of MUAs develops faster and more efficiently than that of non-underreamed anchors but is lost faster after the load reaches its peak value. There are two failure modes of MUAs, namely arch-shaped and cylindrical failure modes. Both of them involve three processes: initial cracking, crack deflection, and crack penetration. The ultimate capacity of ground anchors is composed of end and side bearing capacity. For MUAs, both the side and end resistance effects are improved. Owing to the superposition of the two kinds of effects, the ultimate capacity of MUAs is higher than that of non-underreamed anchors. [ABSTRACT FROM AUTHOR]

Many designs of anchor cables are currently in use for rock support in civil and mining operations. Because of the exposed surface and weak shear performance of the cable bolt's free section (CBFS) in end-anchored structures, breaking failure frequently occurs. Numerical simulations and laboratory experiments were performed in this study to develop measures to improve CBFS resistance to shear failure. Analysis of shear characteristics of the CBFS showed that higher axial tension weakens the cable bolt's shear resistance, and that shear damage on the cable surface and uneven distribution of shear stress aggravate CBFS tensile–shear failure. A high-strength steel pipe is proposed to protect the shear cable bolt, and the preliminary design of a CBFS-strengthening device (CFSD) is presented. Numerical simulation revealed that the CFSD effectively improved CBFS shear resistance and provided protection from harmful shear damage. The optimal performance of a Q-type (slotted steel pipe) CFSD was confirmed. The mechanism of improvement of the cable's shear resistance to surrounding rock by employing the CFSD was analyzed. Double-shear tests were carried out on a bare cable bolt and a cable bolt with a Q-CFSD. The results revealed that the CFSD increased the peak shear force on the joint plane, cable peak axial force, and ultimate shear displacement by 31%, 18%, and 11%, respectively. The proposed device is effective in improving the shear performance of end-anchored cable bolts and enhancing surrounding rock stability. [ABSTRACT FROM AUTHOR]

An experimental test program was performed on grouted post-tensioned anchor rods to determine if anchors with high rod-to-duct area ratios could reanchor themselves upon fracture. Liftoff testing of the grouted anchors was also performed. Results of the study revealed the specimens were capable of reanchoring themselves over a short transfer length and possessed a significant amount residual bond strength following liftoff testing. A theoretical model was created to predict the transfer length phenomenon, which was founded on linear interference fit assumptions. The results between the physical tests and theoretical model demonstrated feasibility in the approach and assumptions. [ABSTRACT FROM AUTHOR]

Plate anchors have become an attractive technology for anchoring offshore floating facilities such as floating renewable energy devices because they provide high holding capacity relative to their dry weight. This allows for the use of smaller anchors (relative to a driven or suction-installed pile), which provide cost savings on production, transport, and installation. Loads delivered to the anchor via mooring lines may increase pore water pressure in fine-grained soils. This excess pore pressure will dissipate with time, resulting in a local increase in the undrained shear strength of the soil surrounding the anchor, increasing the capacity. There may be opportunities to consider these capacity increases if the consolidation process occurs over time periods that are short relative to the lifetime of the facility. This paper considers the use of drainage channels in a plate to make the anchor permeable and quicken consolidation times. Experimental data generated from model-scale experiments conducted in a geotechnical centrifuge show (for the anchor design tested) that excess pore pressure just above the anchor dissipated almost an order of magnitude faster for a permeable anchor, and that after full consolidation, the permeable anchor capacity was higher. The latter finding was not anticipated and is believed to be due to changes in load distribution resulting from the rapid reduction in negative excess pore pressure underneath the permeable anchor. [ABSTRACT FROM AUTHOR]

An important research topic in reinforcing deep soft soil slopes is the pullout distribution of a long anchor with multiple grout bulbs under various factors. The nonlinear variation between the compaction effect and grout bulb diameter was first quantitatively described using an exponential model. The pullout force of a long anchor with multiple grout bulbs was then calculated using a modified model considering the compaction effect. After verification based on the model test data, a parametric analysis was carried out on the elastic modulus of the anchor rod, grout bulb diameters, bulb numbers, and bulb sequences. The results indicated that a larger elastic modulus leads to a more obvious hardening behavior and a lower mobilized displacement of the pullout force. The grout bulb diameter significantly influences the ultimate pullout force and the mobilized displacement of the pullout force. Although the bulb number affects the ultimate pullout force and the distribution of the pullout force, the mobilized displacement of the pullout force does not change. For a long anchor with multiple grout bulbs, the sequence of the bulb diameters has a significant impact on the ultimate pullout force and the distribution and mobilized displacement of the pullout force. [ABSTRACT FROM AUTHOR]

Nowadays, plate anchors have many applications in onshore and offshore projects. These plates can be used vertically or horizontally in their application. For the stabilization of retaining walls, vertical plate anchors are used, and some research on the performance of single plate anchors has been carried out. However, few studies have considered the effect of using multiplate anchors for mechanically stabilized earth walls, and therefore more research is required in this area. In the present study, the effects of the number of plate anchors, the inclination angle of plate anchors, the distances between plate anchors, and the change in the ratio of loading heel distance (d) to wall height (H) under constant strain loading was determined experimentally. To capture the type and location of the critical slip surface occurring in the wall and the effects of variables on the shape of a failure wedge, the particle image velocimetry (PIV) method was used. According to the results, the triple plate anchors indicated the lowest horizontal displacement and the highest bearing capacity compared with single and double plate anchors. By increasing the inclination angle of the plate anchors from 0° to 60°, the horizontal displacement increased, and alternatively, the bearing capacity decreased. By reducing the ratio of d/H from 0.4 to 0.2, the horizontal displacement of the wall increased and the bearing capacity decreased. Moreover, the PIV results showed that by increasing the inclination angle of the plate anchors, reducing the distance between the plates, and decreasing the ratio of d/H, the width of the critical slip surface and movement of soil particles increased. [ABSTRACT FROM AUTHOR]

The development of efficient photocathodes is of critical importance for the constructions of promising tandem photo‐electrochemical cells. Most known dye‐sensitized photocathodes are prepared with the conventional carboxylic or phosphonic acid anchors and require the presence of other terminal linking groups to connect catalysts; they suffer from high synthetic difficulty and low adsorption stability in aqueous media. Here, a compact bilayer photocathode has been prepared by using a pyrene‐based photosensitizer with multiple terminal pyridine moieties as both the anchoring and linking groups to connect a Co hydrogen‐evolution catalyst to the NiO substrate. The catalyst and dye molecule are assembled in a layer‐by‐layer manner on NiO through the metal‐pyridine coordination. This photocathode exhibits good dye adsorption stability in aqueous media. A stable cathodic photocurrent of 70 μA cm−2 was achieved, with H2 being generated at the photocathode under the visible‐light irradiation. The Faraday efficiency of H2 evolution was estimated to be 9.1 %. Transient absorption spectral studies suggest that the interfacial hole transfer occurs within a few picoseconds. The integration of the organic photosensitizer with pyridine anchoring and linking groups is expected to provide a simple method for the fabrication of stable and efficient photocathodes. [ABSTRACT FROM AUTHOR]