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Fastenings in concrete are widely applicable in construction. A significant benefit of fastening technology lies in the fact that it can adapt to various geometries and construction sequences. As a result, the need to design and realize a fastening in structural elements with unconventional geometric configurations can be encountered. Existing design standards rely on the concrete capacity design (CCD) method for concrete‐related failures, which typically covers detailing situations with rectangular configurations of the fastenings and the concrete members. However, the lack of guidelines for a wider range of applications may lead to over‐conservative dimensioning or design constraints. This study investigates the influence of beveled concrete edges on the load‐bearing behavior of anchors. As part of the research, a series of experiments and numerical simulations were conducted. The results derived from the investigations are used to develop an analytical concept that extends the area of applicability of the CCD method and can be used for reliable dimensioning of fastenings close to non‐rectangular concrete edges and geometrical boundaries. [ABSTRACT FROM AUTHOR]

The route of the D1 highway in the Lietavská Lúčka - Dubná Skala section near Žilina is taken forward by a 17m deep cut in a section about 300m long. The first proposed solution of the highway route was based on the assumption that it is a stable area. However, during the construction of the highway cut an old landslide area with a depth of shear surfaces of up to 25m was identified right in the area of the cut. Therefore, massive measures had to be designated to assure that the area above the highway and the access to the tunnel portal were not threatened by landslides. When addressing the security of the cut, an unusual solution was used - anchored diaphragm wall panels of underground concrete walling oriented towards the slope. Currently, this given solution is under construction and is controlled by inclinometers incorporated into selected diaphragm wall panels. [ABSTRACT FROM AUTHOR]

Deciding how many anchors to use in a Bankart repair is challenging because of the desire to enhance stability while avoiding a postage-stamp fracture of the glenoid rim. This controlled laboratory study investigated load to fracture of the anterior glenoid rim after drilling holes of varying number and diameter and inserting anchors of 2 different types and sizes, with and without perforation of the medial cortex of the glenoid, creating postage-stamp fractures using a metallic humeral head that was compressed against the anterior glenoid rim. A destructive model with a servohydraulic load frame was used to test 46 synthetic scapulae with compressive strength and elastic modulus similar to that of a human glenoid. Load to fracture of the intact glenoid was compared with groups with a varying number of anchor holes of different diameters, with anchors of different sizes and types, and with anchors perforating or not perforating the glenoid medial cortex. The percentage of force to fracture an intact specimen was used to identify relative risk of fracture: low risk >75%, moderate risk 75%-50%, and high risk <50% of intact load. The load to fracture of intact glenoids was 1276 ± 42 N. Loads decreased linearly as the number of holes drilled on the glenoid rim increased. Compared with the 1.6-mm group, the 3.0-mm group had significantly lower glenoid rim strength in specimens with 4, 5, and 7 holes (P =.013,.032, and.045, respectively). All-suture anchors in 1.6-mm holes did not alter the glenoid rim strength, and up to 5 anchors were associated with low risk of fracture. Load to fracture was significantly higher with 3.0-mm rigid core bioabsorbable anchors with 4 anchors (1081 ± 6 N) compared with the 4-hole condition (838 ± 107 N; P =.033). Perforating the glenoid medial cortex with five 1.6-mm anchors significantly weakened the glenoid rim to 58% of intact (P =.012). Perforating the medial cortex weakened the glenoid rim to 52% and 42% (P <.001 for both) of intact in the 3.0-mm 4-anchor and 5-anchor constructions, constituting moderate and high risk of fracture, respectively. Up to five 1.6-mm all-suture anchors and four 3.0-mm bioabsorbable rigid-core anchors were associated with low risk of fracture of the glenoid rim. Smaller diameter all-suture anchors best preserved structural integrity of the glenoid rim, whereas tunnel enlargement and perforation of the glenoid medial cortex were associated with moderate or high risk of a postage-stamp fracture. [ABSTRACT FROM AUTHOR]

Background. Peristomal skin complications (PSCs) pose a major challenge for people living with an ostomy. To avoid severe PSCs, it is important that people with an ostomy check their peristomal skin condition on a regular basis and seek professional help when needed. Aim. To validate a new ostomy skin tool (OST 2.0) that will make regular assessment of the peristomal skin easier. Methods. Seventy subjects participating in a clinical trial were eligible for the analysis and data used for the validation. Item-level correlation with anchors, inter-item correlations, convergent validity of domains, test-retest reliability, anchor- and distributionbased methods for assessment of meaningful change were all part of the psychometric validation of the tool. Results. A final tool was established including six patient reported outcome items and automatic assessment of the discolored peristomal area. Follow-up with cognitive debriefing interviews assured that the concepts were considered relevant for people with an ostomy. Conclusion. The OST 2.0 demonstrated evidence supporting its reliability and validity as an outcome measure to capture both visible and non-visible peristomal skin complications. [ABSTRACT FROM AUTHOR]

Integral components of suspension bridges are anchor spans, consisting of separate strands splayed from the main cable between the splay saddle and the front anchor plane. The main cable is separated into several strands and anchored to the anchorage through the twisting and dispersion of the splay saddle. Tensions in the anchor span strands are related to the overall structural safety of the suspension bridge, the geometric form, and internal stresses in the main cables generated in the completed bridge state. Therefore, the calculation and analysis of anchor span tension are particularly significant. Meanwhile, analyzing tensions in the anchor span strands is quite problematic, insofar as each strand in the saddle groove of the splay saddle is horizontally and vertically bent and then into a spatial catenary, while individual strands form a complex spatial system. This study first determines the spatial orientation of the anchor span strands passing over the splay saddle and their positions relative to the splay saddles. Analytical solutions are found by assuming that the strand tensions are equal at the point of tangency in each strand in the completed bridge state. Therefore, it can be ensured that the tensions in the anchor span strands are equal, which further leads to a sufficiently high safety factor for the cable strands. Given that the strands are separated from each other, an analytical approach is adopted for geometric coordination and mechanical analysis. Tensions in all anchor span strands, tangent position, and angle of each strand in the splay saddle can be determined quickly and precisely. A regular distribution pattern about the calculation results is observed according to the relative position of strands. A comparative validation is performed for strand tensions calculated theoretically against the measured values in a calculation example, proving the feasibility and high accuracy of the proposed method. [ABSTRACT FROM AUTHOR]

The interaction mechanism between grouted anchor cables and the surrounding rock mass or soil are complicated and difficult to investigate using conventional monitoring technologies. This study focuses on the in-situ pullout behavior of grouted anchor cables using Brillouin Optical Time-Domain Analysis technique. A series of pullout tests were conducted on anchor cables with five different anchor lengths and three grouting methods. Distributed fiber optic sensors were used to measure the strain distribution of cable bolts from tip to top. The in-situ pullout test results show that both ultimate pullout resistance and ultimate displacement at the ultimate pullout resistance increase with anchor length. The bond strength suffers a slight variation with an increase in anchor length. Both ultimate pullout resistance and the ultimate displacement for Type-B grouting (grouting with reaming) and Type-C grouting (secondary grouting) are larger than those for Type-A grouting (one-time grouting). The shear bond strength of Type-C grouting is greater than that of Type-A grouting. Results from Gaussian functions analysis show that it is feasible to use the function to characterize the axial stress of anchor cables. Furthermore, the overall mobilized percentage η was evaluated. The anchor cables with smaller anchor lengths will result in greater η. The η for the anchor cables of 6 m reaches 92% at the last load, whereas the anchor cables of 18 m were mobilized by only 29% at the last load. The grouting method has a negligible effect on the η, increasing from 22% to 29% in process of the pullout test. [ABSTRACT FROM AUTHOR]

As a load distributive compression anchor (LDCA) consists of multiple anchor bodies and unbonded tendons, the load applied to the tendon is transmitted to grout and ground by the movement of each anchor body installed along the anchor length. Therefore, the load transfer behavior of LDCA is affected by the interference between adjacent anchor body, and the effect of multiple anchor bodies should be considered in the LDCA design. This study performed a series of pull-out field tests on LDCAs installed in soft rock. LDCAs were designed to have various number and spacing of anchor bodies to investigate the effect of multiple anchor bodies. Furthermore, the test results were compared with the results of pull-out field tests conducted on weathered rock to examine the effect of ground conditions. The load-displacement relationship showed that the grout failure occurred in the LDCA installed in soft rock, and thus the ultimate bearing capacity was smaller than that of the LDCA installed in weathered rock. Additionally, the grout axial load distribution indicated that the LDCA installed in soft rock expressed tensile stress in the grout due to the effect of multiple anchor bodies leading to the tensile failure on the grout. [ABSTRACT FROM AUTHOR]

This paper presents a part of an extensive experimental campaign performed at the National Technical University of Athens (NTUA) with the purpose of investigating the behavior of chemical anchors embedded in solid brick masonry. Anchors are tested in tension under monotonic or repeated loading. All tests are performed under displacement-controlled conditions. The experimental setup and the instrumentation are presented, along with the investigated parameters and the rationale for the selection of the values of those parameters. In this part of the experimental work, comprising fifty-six (56) tests, the examined parameters are the anchor locations (in mortar joints and in the center of bricks), the state of the substrate (cracked or uncracked), the width of the crack crossing the anchor or at its vicinity (up to 1.20 mm), as well as the loading history (monotonic or repeated). In the tests presented herein, the embedment length of the anchors is equal to 100 mm. The anchors are embedded in solid brick masonry wallettes, and subjected to a normal compressive stress equal to 0.20 MPa. The observed failure modes are explained, and the overall behavior of anchors subjected to tension is presented and commented upon, along with the effect of the investigated parameters on the measured tension resistance, and on the corresponding displacement. [ABSTRACT FROM AUTHOR]

Person Search is a task involving pedestrian detection and person re-identification, aiming to retrieve person images matching a given objective attribute from a large-scale image library. The Person Search models need to understand and capture the detailed features and context information of smaller objects in the image more accurately and comprehensively. The current popular Person Search models, whether end-to-end or two-step, are based on anchor boxes. However, due to the limitations of the anchor itself, the model inevitably has some disadvantages, such as unbalance of positive and negative samples and redundant calculation, which will affect the performance of models. To address the problem of fine-grained understanding of target pedestrians in complex scenes and small sizes, this paper proposes a Deformable-Attention-based Anchor-free Person Search model (DAAPS). Fully Convolutional One-Stage (FCOS), as a classic Anchor-free detector, is chosen as the model's infrastructure. The DAAPS model is the first to combine the Anchor-free Person Search model with Deformable Attention Mechanism, applied to guide the model adaptively adjust the perceptual. The Deformable Attention Mechanism is used to help the model focus on the critical information and effectively improve the poor accuracy caused by the absence of anchor boxes. The experiment proves the adaptability of the Attention mechanism to the Anchor-free model. Besides, with an improved ResNeXt+ network frame, the DAAPS model selects the Triplet-based Online Instance Matching (TOIM) Loss function to achieve a more precise end-to-end Person Search task. Simulation experiments demonstrate that the proposed model has higher accuracy and better robustness than most Person Search models, reaching 95.0% of mean Average Precision (mAP) and 95.6% of Top-1 on the CUHK-SYSU dataset, 48.6% of mAP and 84.7% of Top-1 on the Person Re-identification in the Wild (PRW) dataset, respectively. [ABSTRACT FROM AUTHOR]

Cast-in-place anchors are being increasingly used in many applications including building construction, bridge, and power plants. The anchorage to concrete systems are subjected to tensile, shear and combined loads from a variety of loading circumstances including static, dynamic, and shock loading. Despite extensive studies on these systems, reliable numerical models for predicting the behavior of these anchors are still limited. Therefore, this paper investigated the tensile behavior of cast-in-place anchorage to concrete systems, to propose an effective model for reproducing anchorage behavior using finite element (FE) methods. Experiments and code-based models for the anchorage system in tension were used to evaluate the numerical models for cast-in-place anchors in concrete, and the most suitable model, with advantages in accuracy and saving analysis time, was chosen. Finally, the FE model was used to study the tensile capacity and related dynamic increase factor for various strain rates, anchor diameters, and embedment depths. [ABSTRACT FROM AUTHOR]

[Display omitted] Conventional coating strategies and materials for bio-applications with protective, diagnostic, and therapeutic functions are commonly limited by their arduous preparation processes and lack of on-demand functionalities. Herein, inspired by the 'root-leaf' structure of grass, a series of novel polyacrylate-conjugated proteins can be engineered with sticky bovine serum albumin (BSA) protein as a 'root' anchoring layer and a multifunctional polyacrylate as a 'leaf' functional layer for the facile coating procedure and versatile surface functionalities. The engineered proteins were synthesized based on click chemistry, where the 'root' layer can universally anchor onto both organic and inorganic substrates through a facile dip/spraying method with excellent stability in harsh solution conditions, thanks to its multiple adaptive molecular interactions with substrates that further elucidated by molecular force measurements between the 'root' BSA protein and substrates. The 'leaf' conjugated-polyacrylates imparted coatings with versatile on-demand functionalities, such as resistance to over 99% biofouling in complex biofluids, pH-responsive performance, and robust adhesion with various nanomaterials. By synergistically leveraging the universal anchoring capabilities of BSA with the versatile physicochemical properties of polyacrylates, this study introduces a promising and facile strategy for imparting novel functionalities to a myriad of surfaces through engineering natural proteins and biomaterials for biotechnical and nanotechnical applications. [ABSTRACT FROM AUTHOR]

The rapid development of ultra-high towers of long-span bridges has put forward higher requirements for the design and construction of embedded parts in terms of safety, operability, and post-repair. The paper proposes a steel plate embedded heavy-load corbel, which has the advantages of high bearing capacity (逸350 t), recycling use, small damage to the bridge tower, and easy repair. The mechanical behaviors and failure modes were studied by numerical analysis and full-scale loading test. The results show that curves of load-stress of the corbel show linear behavior, and there is no obvious wrinkle and buckling after test unloading. The failure modes of the anchored concrete is the oblique crack caused by punching, the crack width meets the limit requirements, and closes after test unloading, which has no adverse effect on the tower. The steel plate embedded corbel has good mechanical behaviors and can be used as a selection for large corbel. The study provides test data for further research and supports to the heavy-load embedded parts. [ABSTRACT FROM AUTHOR]

In order to study the influence of split grouting times on the anchorage performance of prestressed anchor cable, a field test of multisplit grouting was carried out using fiber Bragg grating monitoring technology. The ultimate bearing capacity, displacement, axial force, and shear stress distribution of the anchor cable under different split grouting times were studied. The test results show that (1) compared with conventional grouting methods, multiple split grouting can increase the bearing capacity of the anchor cable by two to three times, and the improvement effect is most obvious in secondary grouting; (2) the number of split grouts has no effect on the axial force of the anchorage section and does not change the shear stress distribution of the anchorage section. The axial and shear stresses of the anchor cable are mainly concentrated at the first 8 m of the anchorage section. With the increasing tension load, debonding and sliding will occur at the front of the anchorage section, and the peak shear stress will move to the depth of the anchorage section. (3) When the anchor cable fails, the total displacement increases with the increase in splitting and grouting times. The conventional grouting anchor cable begins to produce plastic displacement early, while the plastic displacement of the split grouting anchor cable occurs when the external load is close to the failure load. (4) The multiple high-pressure split grouting technology is applicable to the reinforcement of foundation pits or slope engineering and is a valuable support and reinforcement technology. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to simulate the tension process of tension-type anchor cable and to explore the mechanical characteristics and tension-torsion coupling effect of anchor cable subjected to tension. Design/methodology/approach: ABAQUS numerical software is applied to construct the numerical models of tension-type anchor cables with different diameters. Through explicit contact, the characteristics of contact between grouting body-anchor cable and grouting body-rock mass are determined. Confining pressure is applied to the model through surface pressure, and drawing force is applied to the model by displacement loading so as to simulate the tension process of the anchor cable. Findings: The results show that the stress is transmitted in both axial and radial directions in the anchorage section and distributed in a cone. The shear stress in the grouting body is unevenly distributed, and its peak value increases with the rise in confining pressure and anchor cable diameter. The stress characteristics of torque and axial force are basically consistent and evenly distributed in the free section; they gradually decrease in the anchorage section. Due to the tension-torsion coupling effect, the internal stress characteristics of the anchor cable structure vary. On average, the anchorage performance of each anchor cable model is improved by 6.19%. Originality/value: The proposed method of numerical modelling is effective in addressing the interface contact between the anchor cable and the grouting body and in solving the problem with convergence of calculation. Compared with the indoor test, this method is more suited to collecting the internal mechanical data of the anchor body. [ABSTRACT FROM AUTHOR]

The article presents experimental tests carried out to investigate the effect of crack width (0.4, 0.8, 1.5, and 3.0 mm) on the behavior of anchor bolts under static and dynamic loading. Ultimate loads for anchors reached 220 kN depending on the anchor type, the diameter, and the crack opening width. Mechanical and bonded anchors were studied as the most frequently used anchor types. Two states of concrete, resulting from the design earthquake and the maximum considered earthquake, were simulated in the course of the experiments. Within the framework of the study, dependencies between the bearing capacity and stiffness of anchorages, on the one hand, and the level of concrete damage, on the other hand, were identified for different types of anchors. The data, generated in the course of the study, were used to identify the types of anchorages recommended for embedment in seismic areas. Plasticity coefficients and seismic load reduction coefficients were determined for different types of anchors and levels of concrete damage as a result of experimental studies. Reduction coefficients can be contributed to the design of anchorages embedded in seismic areas. [ABSTRACT FROM AUTHOR]

Compared to traditional steel reinforcement, GFRP anchors demonstrate outstanding mechanical performance and corrosion resistance, and so they are an ideal substitute for steel reinforcement in anti-floating projects. Based on finite element software, a 3D axisymmetric calculation model of GFRP anti-floating anchors in medium-weathered granite was established in this paper. Combined with the in-situ ultimate pull-out tests, the bonding anchoring performance and bearing characteristics between the anchor body, anchoring mortar, and rock–soil mass were analyzed. The research findings indicated that the cohesive bonding elements exhibited a high degree of conformity in defining the interface contact relationship of the GFRP anti-floating anchor anchoring system. The axial force of the GFRP anti-floating anchor body is "attenuated" along the depth direction, and there was a critical value of anchoring length; under the same conditions, the reasonable anchoring length should be 3.5~5.0 m. All the anchors in the in-situ tests exhibited interfacial shear slip failure between the anchor body and the anchor mortar, with an average maximum load of 450 kN, which is consistent with the maximum failure load of the simulated anchors. Compared to a load of 50 kN, the maximum stress of the anchor mortar increased by 50% under a load of 450 kN. The displacement variation of the surrounding rock–soil mass showed a decreasing trend from the inside to the outside and from the top to the bottom. The research results provided valuable references for the optimization design of GFRP anti-floating anchors. [ABSTRACT FROM AUTHOR]

Rapid advancements in construction technologies have accelerated the development of complex and deep underground structures, raising concerns about the impact of groundwater on structures, particularly anti-floating measures. Traditional tensioned anchors, commonly used for preventing flotation, suffer from limitations like low pull-out bearing capacity, shallow critical anchoring depth, and localized stress concentration. To overcome these limitations, this paper introduces a tension–compression dispersed composite anchor, which combines casing, load-bearing plates, and tensioned anchors. Comparative tests were conducted between these composite anchors and traditional tensioned anchors to analyze their anchoring behavior. Our results show that tensioned anchors exhibit a stable axial force distribution as anchoring length increases. By identifying abrupt changes in the axial force curve, optimal anchoring lengths for load-dispersed anchors can be determined, thereby enhancing rock and soil strength utilization. The tension–compression-dispersed composite anchor outperforms tensioned anchors, with 1.44 times the ultimate bearing capacity for equivalent anchoring lengths and 1.1 times the capacity for an additional 1 m length. It also displays superior deformation adaptability and structural ductility under high-bearing loads compared to tensioned anchors with extended anchoring lengths. Effectively mobilizing the strength of the lower anchoring segment within the rock and soil results in a lower critical anchoring depth and a more uniform distribution of lateral friction resistance. In conclusion, the tension–compression-dispersed composite anchor offers significant advantages, making it a promising engineering solution for anti-floating anchor systems in complex underground environments. [ABSTRACT FROM AUTHOR]

In regions with high-stress roadway stress, anchor cables frequently experience damage, leading to risky pull-outs and ejections. This study aimed to determine the dynamics of such incidents, refine protective devices, and validate their efficacy in enhancing safety. Drawing from an ejection accident in the 1632 (3) roadway of Pan San Mine, a combination of laboratory experiments, theoretical analysis, simulations, and field applications was utilized. The kinetic energy and speed of cable ejections were determined from single-axis tension test data. Based on these insights, a spring-based protection device was conceptualized. Subsequent experiments and simulations evaluated the energy absorption and deformation characteristics of these devices with different diameters. The results included the following: A cable, during ejection, moved at 48 m/s. Spring protective devices of 4 mm can absorb more energy than the 5 mm, but the anti-ejection effect is poor respectively. Increasing the device diameter improved its performance, especially in controlling spring deformation rate and preventing cable lock-ups. This devised protection mechanism showed promising results when implemented in the 1511 (1) roadway of Zhangji Mine. [ABSTRACT FROM AUTHOR]

Anchorage failure of a suction anchor is more likely to occur in low-strength muddy clay. This paper focuses on the failure behaviors of suction anchors and muddy clay stress responses. The centrifugal model test was used to study the loading processes of suction anchors with various pulling angles. Firstly, the multi-stage developing process of anchoring force was analyzed according to the test results. Numerical modeling was used to validate the test results. The displacement of the suction anchor and muddy clay soil were analyzed using the numerical results. Then, the numerical and testing results were compared to analyze the horizontal soil pressure responses around the suction anchors. It was found that the change in loading direction affected the distribution and development of soil stress. The horizontal soil resistance played a crucial role in improving the bearing capacity. The soil stress variation and anchor displacement revealed that the suction anchors exhibited multi-attitude coupling movement during the inclined pulling. The vertical pulling suction anchor showed shear–slip failure behaviors, while the inclined pulling suction anchors showed compression–shear–slip coupling failure behaviors. The results of this study provide insight into the interaction mechanism between suction anchors and muddy clay, serving as a reference for the design and application of suction anchors. [ABSTRACT FROM AUTHOR]

Increasing the water–cement ratio and water-reducer dosage of cement slurry enhances its fluidity. However, a high water–cement ratio diminishes the beneficial effects of water reducers on fluidity. The stone content of the slurry decreases as the water-reducer dosage increases. Additionally, the water–cement ratio significantly affects stone content. However, when the water–cement ratio exceeds a threshold value, stone content decreases. Furthermore, the threshold value of the water–cement ratio decreases with increasing water-reducer dosage. Without the addition of the water reducer, as the water–cement ratio increases the overall integrity of the grout stone decreases. The addition of the water reducer alters the surface pore distribution, wherein "uniform small pores" change to "localized large pores." Based on the multi-objective optimization of Matlab, the recommended optimal mix composition for a slow-setting cement slurry is a water–cement ratio of 0.25 and water-reducer dosage of 1.5%. With the use of this optimized mix composition, the stone content and compressive strength increase by 7.8% and 145.6%, respectively, compared to those obtained using the recommended mix ratio in the specifications. Additionally, all relevant performance parameters meet the requirements specified by previous standards. [ABSTRACT FROM AUTHOR]

The implementation of roof bolt support within a coal mine roadway has the capacity to bolster the stability of the encompassing rock strata and thereby mitigate the potential for accidents. To enhance the automation of support operations, this paper introduces a binocular vision positioning method for drilling holes, which relies on the adaptive adjustment of parameters. Through the establishment of a predictive model, the correlation between the radius of the target circular hole in the image and the shooting distance is ascertained. Based on the structural model of the anchor drilling robot and the related sensing data, the shooting distance range is defined. Exploiting the geometric constraints inherent to adjacent anchor holes, the precise identification of anchor holes is detected by a Hough transformer with an adaptive parameter-adjusted method. On this basis, the matching of the anchor hole contour is realized by using linear slope and geometric constraints, and the spatial coordinates of the anchor hole center in the camera coordinate system are determined based on the binocular vision positioning principle. The outcomes of the experiments reveal that the method attains a positioning accuracy of 95.2%, with an absolute error of around 1.52 mm. When compared with manual operation, this technique distinctly enhances drilling accuracy and augments support efficiency. [ABSTRACT FROM AUTHOR]

Taking the roadway peripheral rock anchoring unit as the research object, the rock compression test containing the anchor solid was carried out to analyze the influence of the degree of peripheral rock fragmentation and the anchor support method on the mechanical properties of the rock body. The test results showed that the smaller the size of the structural surface, the more a greater number of anchor rods were needed, which in turn provided better support. With the increase in the size of the structural surface, the uniaxial compressive strength and modulus of elasticity of the specimen showed a gradual decrease. Numerical tests of the uniaxial compression of rock containing cohesive units showed that the deformation of the specimen near the anchor bar was significantly reduced, while the main rupture surface was blocked, and an obvious reinforcement zone was formed near the anchor bar. Under the double-anchor condition, the anchor tension stress was more obvious, the reinforcement zone was wider, and the rock rupture surface was strongly blocked, all of which made its reinforcement effect the more obvious. This double-anchor condition showed that the anchoring effect of the anchor rods on the specimens was reflected in two aspects of reinforcement and crack stopping. The denser the anchor rods, the wider the reinforcement zone and hence the more likely that the superposition effect will occur, which allowed the anchor rods to play a greater supporting role in stabilizing the rock. The research results can provide a theoretical basis for the design of anchor support and early warning prediction of destabilization damage in the fractured surrounding rock of coal mine roadways. [ABSTRACT FROM AUTHOR]

High-strength jute fibre-reinforced polymer (JFRP) laminates have recently been introduced to strengthen RC beams against shear. In contrast to synthetic-based composites, JFRP laminates would be more ductile, compatible with steel shear rebar and effective in reducing debonding due to their lower modulus of elasticity. The prime objective of this research was providing an optimal solution to strengthen a severely deficient RC beam against shear using an externally bonded JFRP laminate with anchor. Fabrication of the JFRP laminate was carried out with the maximum fibre content of 37.5% to obtain high tensile strength. Five full-scale RC beam specimens were cast. Shear strengthening was done by an externally bonded JFRP laminate with double connector, multiple connector and embedded-bar anchor systems. The dimensions of JFRP laminate were obtained based on proposed guidelines. Based on the experimental test, the average tensile strength of the fabricated JFRP laminate was found to be 162 MPa. Results also showed that the JFRP laminate with multi-connector anchor increased the maximum shear capacity of deficient RC beams by 89% and the beams had failed by the fracture of laminate. Beams strengthened with embedded-bar anchor had shown flexural ductile failure. Both beams failed after yielding of flexural bar. The proposed guidelines could be used for shear strengthening of severely deficient beams to enhance the maximum shear capacity using full strength of JFRP laminate with anchor. [ABSTRACT FROM AUTHOR]

In this paper, we show the impact of the outer scale on beam wander for laser beam propagation in non-Kolmogorov turbulence. The analysis is based on a new relation between non-Kolmogorov and Kolmogorov structure constants anchored on the outer scale. This approach is based on a measurable physical entity, the outer scale, and it insures the total power of the fluctuations of the refractive index is conserved when the power law changes. [ABSTRACT FROM AUTHOR]

In 2025 the new generation of the Eurocode 7 will be introduced and set a framework for geotechnical design for the next 20 years. As Eurocode 7 is an essential design code, the changes will affect numerous practising geotechnical Engineers. The paper provides an overview of significant changes in rock engineering design introduced in the new EN 1997 part 3, considering limit state design, durability, reliability, testing and other crucial design aspects. It focuses on the anchor clause revision and first introduced design rules for rock bolts and soil‐nailed structures. The improvements described include distinguishing between different tension supporting elements that have often been confused. Furthermore, the provisions for groundwater control measures influencing the working condition and limit states for all other geotechnical systems that have not yet been comprehensively addressed in the current Eurocode 7 are also clarified. Finally, the design of the described geotechnical structure will also be strongly affected by changes in the overall philosophy of the Eurocodes, which is also explained. [ABSTRACT FROM AUTHOR]

Despite the widespread usage of the anchoring technique in geotechnical projects in Brazil, mainly in underground works and retaining walls, limited research has been carried out on the determination of load capacity in anchors. Ground anchored walls in Brazil are often dimensioned by methodologies that are not satisfactorily adapted to the reality of the national soil. In this context, this work proposes a simplified computational methodology for forecasting the load capacity of anchors in geotechnical projects. To this end, a fuzzy model is proposed using specific selected characteristics of the soils and geometry of tieback wall systems, whose measurements are easier to be obtained when compared with the load capacity measurement itself. For validation, calibration, and application of the model, the results of 40 performance tests (load tests) were used. Thirty-two samples were used to train the algorithm whereas eight were used to test the model. The results obtained using the proposed approach were close to the extrapolated values of the performance tests according to the existing empirical method, showing that the model is a viable alternative for the design of anchors. Finally, the methodology presented in this work seems to be a first step for the prediction of the anchor bearing capacity and therefore it will certainly benefit from the addition of new test databases of different locations around the world. [ABSTRACT FROM AUTHOR]

This paper presents a numerical study assessing the seismic performance of steel moment‐resisting frames (SMRFs) designed with ductile exposed column‐base plate (ECBP) connections employing yielding anchor rods. For their potential use as weak bases, the proposed ECBP detail is designed to accommodate plastic deformations in the anchors. The seismic performance of 2‐ and 4‐story archetype SMRFs with ECBPs is investigated to examine the effects of various base‐connection strengths on the frame collapse mechanisms and probabilities. To this aim, the ECBP connections of each frame are designed for a set of three strength levels, ranging from reduced seismic loads to capacity‐designed forces of the adjoining columns. These designs enable the base responses to vary from highly inelastic (i.e., weak‐base design) to elastic (i.e., strong‐base design) when subjected to earthquake‐induced ground shaking. Nonlinear time history analysis (NLTHA) is extensively performed, applying a suite of assembled ground‐motion sequences (i.e., two ground motions in series) to assess the ECBP connection response and the corresponding frame behavior. Fragility analyses accounting for only the first ground motions in each considered sequence (to derive fragility curves), and the entire ground‐motion sequences (to derive fragility surfaces) are also performed to evaluate the probabilities of frame collapse and base connection failure. Finally, key findings regarding the seismic performance of ductile ECBP connections and their effects on the frame collapse are discussed. The limitations of the study are also outlined. [ABSTRACT FROM AUTHOR]

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Fiber-reinforced polymer (FRP) composites are widely used in the strengthening and retrofitting of reinforced concrete (RC) members to enhance their flexural and shear capacities. Strengthening with FRP systems has been proven effective due to their superior properties such as high strength-to-weight ratio and corrosion resistance. However, the debonding of FRP laminates from the concrete substrate is a major concern as it results in a brittle member failure. Anchorage systems could delay early debonding of the FRP laminates and improve the FRP-to-concrete bond. Carbon FRP (CFRP) spike anchors are commonly used as anchorage systems due to their compatibility with CFRP laminates and versatility to suit a varied range of applications. However, research to study the effects of different anchor parameters on strength enhancement has been limited. Hence, this study investigated the effect of CFRP anchor diameter, embedment depth, and dowel angle on the capacity of concrete beams strengthened with externally bonded CFRP laminates. All beams were tested using the four-point bending flexural test. Test results of anchored strengthened beams showed an increase in load-carrying capacity and CFRP strain utilization of up to 50% and 84%, respectively, when compared to the unanchored strengthened beams. In addition, larger embedment depth and insertion angle showed a significant effect on the capacity of the specimens. Finally, anchoring CFRP laminates with different anchor parameters delayed debonding failure with different anchor failure modes. Increasing the anchor diameter up to 12 mm prevented anchor rupture. Furthermore, increasing the embedment depth increased the beam capacity but resulted in anchor rupture. Anchoring CFRP laminates at large angles shifted the anchor rupture failure to partial anchor pullout. This study demonstrates that CFRP spike anchors, when properly designed and installed, can delay the brittle debonding failure mode, thus enhancing the load-carrying capacity of strengthened members. [ABSTRACT FROM AUTHOR]

Robotic manipulators can interact with large, heavy objects through whole-arm manipulation. Combined with direct physical interaction between humans and robots, the patient can be anchored in care. However, the complexity of this scenario requires control by a caregiver. We are investigating how such a complex form of manipulation can be controlled by nurses and whether the use of such a system creates physical relief. The use case chosen was washing the back of a patient in the lateral position. The operability of the remote control from the tele-nurse's point of view, the change in the posture of the nurse on site, the execution times, the evaluation of the cooperation between human and robot, and the evaluation of the system from the nurse's point of view and from the patient's point of view were evaluated. The results show that the posture of the worker improved by 11.93% on average, and by a maximum of 26.13%. Ease of use is rated as marginally high. The manipulator is considered helpful. The study shows that remote whole-arm manipulation can anchor bedridden patients in the lateral position and that this system can be operated by nurses and leads to an improvement in working posture. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The optimal insertion torque (IT) for orthodontic anchoring screws (OASs) was hypothesized to vary with OAS features and insertion methods. This review examines the indexed English literature, to determine the appropriate IT range for OAS success based on area of insertion and OAS features. Eleven original articles with OAS placement in humans including IT and success rate were selected and were used to evaluate the relationships among IT, success rates, screw design, and placement methods at different sites. The ITs and success rates ranged from 6.0 ± 3.2 to 15.7 ± 2.3 Ncm and from 62.5 to 100.0% in the upper and lower buccal alveolar areas, respectively. For the mid-palatal area, the range was 14.5 ± 1.6 to 25.6 ± 5.5 Ncm and 83.0 to 100.0%, respectively. ITs of 5–12 and 6–14 Ncm were found to be optimal for the commonly used φ1.5–1.7 mm OASs in the upper and lower interproximal areas, respectively. In the mid-palatal suture area, ITs of 11–16 and 20–25 Ncm were considered suitable for tapered φ1.5 mm and φ2.0 mm OASs, respectively. Although identified optimal IT ranges deserve the recommendations, care must be taken to monitor the IT during placement constantly. [ABSTRACT FROM AUTHOR]

The expansion stud anchor bolt is one of the most used construction materials due to its flexibility in installation and connecting structural members. However, due to the geographic condition of the Philippines, consisting of 7,107 islands with 36,289 kilometers of coastline, water particulates from seawater increased the corrosion process of any steel material, including expansion stud anchor bolts. The objective of the study is to use neural network modeling to determine the effect of corrosion on the pull-out capacity of an expansion stud anchor bolt as influenced by corrosion considering different parameters such as Half-cell Potential, Gravimetric Test Result, compressive strength of concrete, and presence of waterproofing. The Impressed Voltage Technique (IVT) accelerated the corrosion process on 35 pieces of 250 mm x 250 mm x 150 mm concrete samples with and without waterproofing admixture, installed with uncorroded expansion stud anchor bolts. The behavior of the pull-out capacity, including the order of importance of the input parameters, was analyzed using neural network modeling. Among the parameters considered, the number of days subjected to IVT, which accelerated the corrosion process, is the primary and most significant variable in influencing the pull-out capacity of an anchor bolt. [ABSTRACT FROM AUTHOR]

Submerged floating tunnels (SFTs) are novel structures for transportation across long- and deep-strait regions. Owing to severe wave and current excitation as well as the effects of underwater structures and corrosion, the risk of local anchor cable failure is high, which can result in the progressive failure of the entire structure. In this study, experimental and numerical investigations are conducted to analyze the dynamic behavior of an SFT with different mooring styles under local cable failure. A custom-designed cable failure device and the birth-and-death element method are used to simulate cable failure (i.e., progressive failure) via experiments and numerical simulation, respectively. A physical-scale segmental model of an SFT with different mooring styles under anchor cable failure is developed in this study. A segmental and entire-length mathematical model is developed using the ANSYS program to perform the numerical simulation. The results of the segmental numerical and experimental models indicate good agreement. The dynamic response of an SFT with different mooring styles under cable failure is comprehensively investigated by investigating the effects of key parameters (wave period, buoyant weight ratio, and cable failure mechanism). Moreover, the progressive failure of the SFT under cable failure is investigated via a segment model test and a numerical simulation of its entire length. The present study can serve as a reference for the safer designs of the SFT mooring style. [ABSTRACT FROM AUTHOR]

Whole-genome alignment (WGA) is a critical process in comparative genomics, facilitating the detection of genetic variants and aiding our understanding of evolution. This paper offers a detailed overview and categorization of WGA techniques, encompassing suffix tree-based, hash-based, anchor-based, and graph-based methods. It elaborates on the algorithmic properties of these tools, focusing on performance and methodological aspects. This paper underscores the latest progress in WGA, emphasizing the increasing capacity to manage the growing intricacy and volume of genomic data. However, the field still grapples with computational and biological hurdles affecting the precision and speed of WGA. We explore these challenges and potential future solutions. This paper aims to provide a comprehensive resource for researchers, deepening our understanding of WGA tools and their applications, constraints, and prospects.

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 Lρ to L2ρ (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 ξ00(ξ00<0) is found, such that positive constant steady state (u∗,v∗,w∗) becomes unstable when ξ<ξ00. 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.