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Retreat of marine outlet glaciers often initiates depletion of inland ice through dynamic adjustments of the upstream glacier. The local topography of a fjord may promote or inhibit such retreat, and therefore fjord geometry constitutes a critical control on ice sheet mass balance. To quantify the processes of ice–topography interactions and enhance the understanding of the dynamics involved, we analyze a multitude of topographic fjord settings and scenarios using the Ice-sheet and Sea-level System Model (ISSM). We systematically study glacier retreat through a variety of artificial fjord geometries and quantify the modeled dynamics directly in relation to topographic features. We find that retreat in an upstream-widening or upstream-deepening fjord does not necessarily promote retreat, as suggested by previous studies. Conversely, it may stabilize a glacier because converging ice flow towards a constriction enhances lateral and basal shear stress gradients. An upstream-narrowing or upstream-shoaling fjord, in turn, may promote retreat since fjord walls or bed provide little stability to the glacier where ice flow diverges. Furthermore, we identify distinct quantitative relationships directly linking grounding line discharge and retreat rate to fjord topography and transfer these results to a long-term study of the retreat of Jakobshavn Isbræ. These findings offer new perspectives on ice–topography interactions and give guidance to an ad hoc assessment of future topographically induced ice loss based on knowledge of the upstream fjord geometry.

We describe elongate, wet, subglacial bedforms in the shear margins of the NE Greenland Ice Stream and place some constraints on their formation. Lateral shear margin moraines have been observed across the previously glaciated landscape, but little is known about the ice-flow conditions necessary to form these bedforms. Here we describe in situ sediment bedforms under the NE Greenland Ice Stream shear margins that are observed in active-source seismic and ground-penetrating radar surveys. We find bedforms in the shear margins that are ~500 m wide, ~50 m tall, and elongated nearly parallel to ice-flow, including what we believe to be the first subglacial observation of a shear margin moraine. Acoustic impedance analysis of the bedforms shows that they are composed of unconsolidated, deformable, water-saturated till. We use these geophysical observations to place constraints on the possible formation mechanism of these subglacial features.

Cable shear behavior in reinforcing rock discontinuities involves both the axial shear behaviour along the cable-grout interface and the local lateral shear behaviour of the cable deflecting section. This is a complex condition which is difficult to be solved in a theoretical manner. Pile structural elements in Flac3D were used here to investigate this shear behavior with special attention to the influence of cable anchorage length. The employed numerical cable model was firstly calibrated using the laboratory pullout test and a single shear test on a plain Superstrand cable bolt. Then the calibrated model was used to investigate the anchorage length effect on the cable lateral shear behavior. As expected, numerical results show that two demarcation anchorage lengths existed in cable shear tests. In the case of plain Superstrand cable bolt subjected to lateral shear loading at an angle of 90°, the two demarcation anchorage lengths were approximately 2.09 m and 0.61 m.

Steel corrugated shear wall (SCSW) is an alternative to traditional shear walls with flat plates. However, shear resistance behavior and design of the infilled corrugated panels in SCSWs has not been well studies. This paper focuses on the shear resistance of sinusoidally corrugated panels in SCSWs under monotonic lateral shear force, via finite element analyses (FEA) considering both geometric nonlinearity and material elasto-plasticity. Firstly the effects of initial imperfections and geometric dimensions on shear resistance of corrugated panels are explored. Then based on extensive FEA, the maximum and the post-buckling strengths are investigated, and fitting equations to predict the shear resistant behavior of corrugated panels are proposed by introducing the normalized height-to-thickness ratio. It is found that, the maximum shear resistance of corrugated panels has a consistent relationship to the normalized height-to-thickness ratio, however variation of the post-buckling resistance is complex and geometric parameters have to be properly chosen to avoid significant strength drop after buckling. The equations proposed agree with the FEA results, and can be utilized in design of corrugated panels in SCSWs.

We report on an instability arising in sub-surface, laterally sheared geostrophic flows. When the lateral shear of a horizontal flow in geostrophic balance has a sign opposite to the Coriolis parameter and exceeds it in magnitude, embedded perturbations are subjected to inertial instability, albeit modified by viscosity. When the perturbation arises from the surface of the fluid, the initial response is akin to a Stokes problem, with an initial flow aligned with the initial perturbation. The perturbation then grows quasi-inertially, rotation deflecting the velocity vector, which adopts a well-defined angle with the mean flow, and viscous stresses, transferring horizontal momentum downward. The combination of rotational and viscous effects in the dynamics of inertial instability prompts us to call this process “Ekman-inertial instability.” While the perturbation initially grows super-inertially, the growth rate then becomes sub-inertial, eventually tending back to the inertial value. The same process repeats downward as time progresses. Ekman-inertial transport aligns with the asymptotic orientation of the flow and grows exactly inertially with time once the initial disturbance has passed. Because of the strongly super-inertial initial growth rate, this instability might compete favourably against other instabilities arising in ocean fronts.

Here we study the evolution of stress and its rotations in the Sumatra–Andaman Subduction Zone (SASZ) after the 2004 Mw 9.2 megathrust earthquake, using moment tensor stress inversions. Models indicate returning of North Andaman stress regime to the inter-seismic oblique-compression, after a short stint of extension. Likewise, Little Andamans experience extension indicating a trench-ward guidance of extensional stresses. Similarly, Nicobar regime is presently normal-oblique, from early post-seismic reverse-oblique, and North Sumatra experiences pure-reverse regime. The influence of the Wharton Basin stress field and 2012 earthquakes on the SASZ fore-arc deformation is also probed. A near-complete co-seismic stress-relief is observed at Nicobar, followed by North Sumatra and Little Andaman. Co-seismic and post-seismic model comparisons indicate strong correlation with zones of co-seismic stress relief and regions of rapid post-seismic reloading. The North Andaman shows a northward compressive shear than the margin-normal component of subduction, as evident from prominent oblique stress regime with lower co-seismic stress relief and lack of post-seismic back rotations. At Andaman Spreading Ridge (ASR), transition from oblique to extensional stress indicates lateral shear to back-arc spreading enhancement.

This paper aims at studying the effect of earthquake loading on the constructional design of a 13-multistorey steel frame residential building from economical point of view. This type of loading should be taken into considerations now in Iraq especially after the earthquake of 7.3 magnitude that occurred in November 2017 near the city of Halabja by about 31 kilometers. The same steel multistory building was designed twice; once with traditional gravity dead and live loading and the second with adding earthquake loading in order to discuss the difference from structural and economical points of view. A commercial package ETABS2018 was used to analyze this 39-meter-high building. The building was analyzed according to the American code ASCE7-10, while it was designed according to AISC 360-10. A huge increase in the steel member amounts in columns, beams, secondary beam, deck slabs were recorded due to taking the seismic load into considerations. More specifically, the steel frame amounts increased due to including earthquake loading, the addition in steel frame section (p-m) interaction ratio was by about 209% and 128% for columns and beams, respectively. Therefore, cost was raised by about 209% and 128%, for columns and beams, respectively. More specifically, the total cost of the building concerning beams and columns increased by 337%. It is worth to mention here that the maximum increase in main steel frame was observed on the storey 10. Whereas, in slabs, the maximum increase that was recorded in main ratio of (p-m) interaction increase was occurred from the storey 8 to the building top. In columns, the main ratio of (p-m) interaction increase was seen on the 8ht, 9th, 10th and 11th storeys due to effect lateral shear forces, and section is not seismically compact for highly ductile members (AISC 341-10 Table D1.1).

As a new non-contact method of measuring object displacement, a coaxial displacement sensor using a lateral shear interferometer with a phase grating is proposed. This proposed method uses a phase grating to generate fringes for the evaluation of displacement by means of spatial frequency analysis. Compared with triangulation-based displacement sensors which are widely used for industrial applications, this sensor makes stable measurement because there is no occlusion, and it has a simpler optical system than other non-contact optical methods. The steel pin gauge was measured by the triangulation-based displacement sensor and by the proposed method respectively, and the results confirmed that stable measurement was performed in any scanning orientation of the pin gauge in the proposed method.

Precise cellular organizations are required for the function of many organs and tissues. It is often unclear, however, how such precise patterns emerge during development. The mammalian hearing organ, the organ of Corti, consists of a remarkably organized pattern of four rows of hair cells (HCs) interspersed by non-sensory supporting cells (SCs). This checkerboard-like pattern of HCs and SCs emerges from a disordered epithelium over several days, yet the transition to an ordered cellular pattern is not well understood. Using a combination of quantitative morphological analysis and time-lapse imaging of mouse cochlear explants, we show here that patterning of the organ of Corti involves dynamic reorganizations that include lateral shear motion, cell intercalations, and delaminations. A mathematical model, where tissue morphology is described in terms of the mechanical forces that act on cells and cellular junctions, suggests that global shear on HCs and local repulsion between HCs are sufficient to drive the tissue into the final checkerboard-like pattern. Our findings suggest that precise patterns can emerge during development from reorganization processes, driven by a combination of global and local forces in a process analogous to shear-induced crystallization.

In this work, theoretical studies have been carried out in order to assess the strength of structural elements of the track superstructure from the impact of a special-purpose passenger carriage. The assessment of the impact of the wagon on the railway track was carried out according to the stresses in the edges of the rail base, stresses in the main area of the subgrade and the stability of the track against lateral shear. The calculations showed that the strength and stability of the structural elements of the track superstructure as a result of the impact on it of a special-purpose passenger carriage model 61-934 meets the regulatory requirements.

This paper developed new steel-concrete-steel (SCS) sandwich composite structures using novel enhanced C-channels (ECs) for civil engineering infrastructures as shear walls, bridge decks, and protective structures. Their structural behaviours have been studied through a series of tests from the component to structural member level. Push-out tests on ECs, two-point loading tests on SCS sandwich beams with ECs (SCSSB-ECs), axial compression tests on SCS sandwich walls with ECs (SCSSW-ECs), in-plane cyclic shear tests and out-of-plane punching shear tests on SCSSW-ECs were carried out to investigate the shear behaviour of ECs, flexural and shear behaviour of SCSSB-ECs, compression behaviour, in-plane seismic behaviour, and out-of-plane punching shear behaviour of SCSSW-ECs, respectively. These studies offered comprehensive information of structural behaviours of SCS sandwich structural members with ECs. Including these experimental studies, corresponding prediction equations were also proposed for ultimate shear resistance and shear-slip behaviour of ECs, flexural and shear resistances of SCSSB-ECs, axial compression resistance, in-plane lateral shear resistance, and out-of-plane punching shear resistance of SCSSW-ECs. Through validations against reported test results, accuracies of these developed prediction equations were confirmed.

This paper deals with an experimental investigation on the shear behaviour of concrete-filled steel tubular (CFST) members. A total of 38 specimens with either circular or square cross-sections were tested. Among these specimens, four were subjected to shear and the rest were subjected to combined axial compression and shear. The main parameters considered were the axial compression ratio ( n = 0–0.75), shear span-to-depth ratio ( m = 0.075–0.75), concrete strength ( f cu = 31.9 or 57.4 MPa), steel ratio ( α s = 0.070 or 0.108) and steel yield stress ( f y = 338.3 or 415.7 MPa). The test results showed that, all the CFST specimens exhibited ductile characteristics. The influences of the parameters on the failure mode, load vs. deformation relationships, shear capacity, and strain development of the tested specimens were investigated. Finally, an existing simplified model for predicting the shear capacity of CFST members under combined compression and shear was also assessed.

While the effects of disc degeneration on compression and rotation motions have been studied, there is no data for shear loading. Clinical research has shown that those with low back pain (a potential consequence of degeneration) experience a 75% greater lateral shear force than those without it. Therefore, the aim was to compare the effect of degeneration on spine segment stiffness and phase angle in each of six degree of freedom (6DOF) loading directions. Fourteen intact functional spinal units (FSU) were dissected from human lumbar spines (mean (SD) age 76.2 (11) years, Thompson grades 3 (N = 5, mild), 4 (N = 6, moderate), 5 (N = 3, severe)). Each FSU was tested in ±6DOFs while subjected to a physiological preload, hydration, and temperature (37°C) conditions in a hexapod robot. A one-way ANOVA between degenerated groups was performed on stiffness and phase angle for each DOF. Significant differences in stiffness were found between mild and moderate degenerative groups in lateral shear (p = 0.001), and axial rotation (p = 0.001), where moderate degeneration had decreased stiffness. For phase angle, significant differences were seen in anterior shear (p = 0.017), and axial rotation (p = 0.026), where phase angle for mild degeneration was less than moderate. Trends of stiffness and phase angle changes between degenerative groups were similar within each DOF. Clinically, the identification of the DOFs that are most affected by degeneration could be used in rehabilitation to improve supplemental stabilization of core muscle groups. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1399-1409, 2016.

Based on the structure of the Michelson interferometer, we present a lateral shearing interference microscopy to achieve the quantitative phase measurement of the transparent microscopic biological cells. For this interference microscopy, two right-angle prisms are used to substitute the two plane mirrors. Then, the lateral shear can be realized by horizontally moving one of the two right-angle prisms along the direction perpendicular to the optical axis. Moreover, the amount of lateral shear can be adjusted freely and can be increased by introducing a larger moving distance and/or simultaneously translating another right-angle prism. To simplify the experimental operation of phase calibration, the averaging method instead of the double exposure method is used to obtain accurate phase information. The subsequent experiments show that the proposed system is portable, compact, easy to implement, effective to control the cost, and capable of successfully obtaining the quantitative phase information of the biological cells.

The objective of this study was to investigate biomechanical loads on the lumbar spine as a function of working in a confined vertical space, consistent with baggage handling inside the baggage compartment of an airplane. Ten male subjects performed baggage handling tasks using confined (kneeling, sitting) and unconfined (stooping) lifting styles. Dependent measures of torso flexion and three-dimensional spinal loads were assessed with an electromyography-driven biomechanical model. Lifting exertions typical to airline baggage handling posed significant risk to the lumbar spine, regardless of lifting style. Statistically significant differences attributable to lift style (stooping, kneeling, sitting) were not observed for peak compressive, lateral shear, or resultant spinal loads, but lifting while kneeling decreased anterior/posterior (A/P) shear spinal loads relative to stooping (p = 0.02). Collectively, kneeling offers the greatest benefit when lifting in confined spaces because of the ability to keep the torso upright, subsequently reducing shear forces on the lumbar spine.

This paper experimentally investigated the shear performance of circular concrete-filled steel tubular (CFST) members with inner profiled steel under lateral shear load. Twenty specimens with inner I or cruciform section profiled steel were tested. Different parameters including shear-span ratio (m = 0.3, 0.4, 0.6, 0.8 and 1.0) and profiled steel ratio (αss = 0.028, 0.031, 0.057 and 0.062) were compared and discussed. Failure modes, shear load versus deflection curves, load-strain curves, ductility and shear capacity of the specimens were investigated. The test results showed that the CFST members with inner profiled steel exhibited good ductility under lateral shear load and the extension of cracks in core concrete can be restrained or delayed owing to the inserted profiled steel. The specimens with diverse shear-span ratios showed various failure modes, i.e., shear failure mode and flexure failure mode. With the increase of m, failure modes changed from shear dominated to flexure dominated failure and shear capacity decreased significantly due to the changing of load transfer mechanism. Moreover, inserted profiled steel had an effect on ductility and shear capacity because of the increasing cross-section area of profiled steel and the composite action between profiled steel and concrete. A simplified formula for predicting shear capacity was proposed and predicted results were generally good agreement with experimental results.

In case the structure is exposed to the high temperature, the lateral shear crack is the major cause exposing the steel bar to the high temperature and also the major cause of the collapse of buildings. In the study, in order to control the lateral shear crack, the presterssing using strands in a reverse direction of the lateral shear crack has applied and the fire resistance test of the PS corrugated web composite beam has been carried out, produced in a corrugated type of the steel to increase the efficiency of the prestressing. As a result of the test, the lateral shear crack introducing the PS has been reduced but it has been concluded that in case the strands are failed, the brittle failure can be taking place.

A calibrated three-dimensional hydrodynamic model was applied to study subtidal water and salt exchanges at various cross sections of the Perdido Bay and Wolf Bay system using the Eulerian decomposition method from 6 September 2008 to 13 July 2009. Salinity, velocity, and water levels at each cross section were extracted from the model output to compute flow rates and salt fluxes. Eulerian analysis concluded that salt fluxes (exchanges) at the Perdido Pass and Dolphin Pass cross sections were dominated by tidal oscillatory transport FT, whereas shear dispersive transport FE (shear dispersion due to vertical and lateral shear transport) was dominant at the Perdido Pass complex, the Wolf-Perdido canal, and the lower Perdido Bay cross sections. The flow rate QF and total salt transport rate FS showed distinct variation in response to complex interactions between discharges from upstream rivers and tidal boundaries. QF and FS ranged from −619 m3·s−1 (seaward) to 179 m3·s−1 (landward) and −13,480–6289 kg·s−1 at Perdido Pass when river discharges ranged 11.0–762.5 m3·s−1 in the 2008–2009 simulation period.

Despite of their outstanding axial strength, CFRP tendons necessitate special anchorage due to their low lateral shear strength. In order to cope with such CFRP tendon, the conventional bond type anchor needs to be improved. The results of bond tests executed on 10-mm diameter CFRP tendons coated with sand and oxide revealed that, even if the average bond strength increases by 3 times compared to the non-coated bare tendon, the coated CFRP tendon still requires excessively long anchored length for bonding. Therefore, this study applies a method enabling to shorten the bonded length and improving further the bond performance compared to sand or oxide coating. The improvement of the bond characteristics is achieved by splitting the ends of the CFRP tendon so as to widen the bonded area by 3.5 times. The test results showed that the anchor performance of the CFRP tendon reaches 95% of its tensile strength making it applicable for the bond type anchor.

The present study utilized an integrated biomechanical modeling approach that was previously developed by the researchers to investigate the effects of position and size of drywall on the physical demands for drywall installers. If the drywall sheets were stored vertically instead of flat, it reduced the required muscle contraction forces and joint reaction forces at the low back and shoulder approximately 8% on average during drywall installation. In particular, the L4/L5 disc compression forces and the absolute values of L4/L5 anterior-posterior shear forces decreased 6.1% and 8.5%, respectively, and at the shoulder during lifting the forces of rotator cuff muscles decreased 9.8%, and the coracohumeral ligament forces decreased 12.8%. The reaction forces at both the GH (glenohumeral) and SC (sternoclavicular) joints were reduced 7.2% and 3.6%, respectively. The larger size (e.g., 4x12 and 4x16) of drywall sheets increased the physical burden for the installers tremendously and could expose them to a higher risk of musculoskeletal injuries and disorders. In some simulations the average low back lateral shear forces increased to 1675 N and 2152 N, respectively. These forces are well above the 1000 N recommended for a single lift. These results indicated that it would be physically too difficult or even impossible for one person alone to lift bigger and heavier drywall sheets. Therefore, sound engineering (e.g., lifting tables) and/or administrative (e.g., two-person team work) solutions to handling oversized drywall sheets are strongly recommended.

Elastic media (a plane) weakened with a periodic system of round holes filled with plugs made of homogenous elastic material with the surface was covered by a homogenous cylindrical film. The plane is weakened by two periodic systems of straight line cracks with connections between edges at the tip regions. General concepts describing a type of problem with a periodic distribution of stresses outside round holes and cracks for lateral shear are proposed. The solution to the problem is reduced to solution of two nonlinear singular integral equations. The solution of these two equations define forces in relation to the tip regions. The condition for the propagation of a crack is formed considering criteria for the limiting shear of bonds inside the material.