•The bearing–curling interaction of ferritic stainless steel thin sheet bolted connections was studied.•Tension tests were conducted on fifteen ferritic stainless steel thin sheet bolted ...connections.•FE models were developed and validated against test results and then adopted to conduct parametric studies.•The effects of key geometric parameters were discussed.•Design analyses were carried out.
This paper presents experimental and numerical studies of ferritic stainless steel thin sheet bolted connections failing by bearing–curling interaction. An experimental programme was firstly conducted on fifteen ferritic stainless steel thin sheet bolted connection specimens, including eleven specimens designed with curling and four specimens designed without curling. The test setup and procedures as well as the key test results, including failure loads, failure modes, load–in-plane elongation curves and load–out-of-plane deformation curves, were reported. Following the experimental programme, a numerical modelling programme was performed, where finite element models were developed and validated against the test results and then used to perform parametric studies to generate further numerical data. Based on the obtained numerical data, the effects of various geometric parameters, including end distances, edge distances, longitudinal spacings and sheet thicknesses, on failure loads of ferritic stainless steel thin sheet bolted connections were discussed. Both the test and numerical data were then used to assess the codified design rules for ferritic stainless steel thin sheet bolted connections susceptible to bearing–curling interaction, as set out in the European code and American specification. On the basis of the assessment results, the European code and American specification were found to respectively underestimate the actual load-carrying capacities by 57% and 18%, on average. Besides, a relevant design method proposed for carbon steel thin sheet bolted connections was assessed for its applicability to ferritic stainless steel thin sheet bolted connections, with the results showing that it provided more consistent failure load predictions than the design codes, but the predicted failure loads were still conservative. Therefore, a revised design formula was proposed and shown to provide improved failure load predictions.
There has been growth in research in the sport of curling over the past few decades. The need for a scoping review is warranted. This study's purpose was to identify and synthesize research evidence ...regarding quantitative variables for a series of components within the sport of curling.
A scoping review of studies published and established within four databases was performed. One independent reviewer selected studies based on a systematic procedure. Inclusion criteria for studies were: (1) interventions that focused on the sport of curling; (2) quantitative in nature; (3) written in English; and (4) published within a peer-reviewed journal, a conference presentation, or a published thesis.
Searching identified 8,467 articles and 94 met the inclusion criteria. Data were organized and synthesized based on the devised research variables from the sport of curling: The curl mechanism of the curling stone; the impact of sweeping on stone trajectory; curling delivery mechanics; wheelchair curling; technology analysis; strategy and tactics; psychological factors; injury occurrences; facility and arena infrastructure; and assessment of curling training and ability. The findings confirm the strong knowledge base that exists across game variables and unveil controversy between the underlying physics that produces curl, as well as the mechanisms of sweeping responsible for manipulating the stone trajectory.
Knowledge derived from this review can assist researchers, coaches, and curlers in addressing the specific variables of the sport that influence stone trajectory and game results. Such awareness will expose gaps in the current understanding and foster new research endeavors to further the knowledge of the sport.
•The bearing–curling interaction of austenitic stainless steel thin sheet bolted connections was studied.•Tension tests were conducted on 26 austenitic stainless steel thin sheet bolted connection ...specimens.•FE models were developed and validated against test results and then adopted to conduct parametric studies.•The effects of end and edge distances, longitudinal and transverse spacings and thickness were discussed.•Design analyses were conducted.
The bearing–curling interactive behaviour and capacities of austenitic stainless steel thin sheet bolted connections are studied in this paper, underpinned by testing and numerical modelling. Experiments were firstly conducted on 26 austenitic stainless steel thin sheet bolted connection specimens, including 19 specimens designed with curling and 7 specimens designed without curling. The test failure loads, failure modes, load–in-plane elongation curves and load–out-of-plane deformation curves were fully reported. The experimental programme was followed by a numerical modelling programme, where finite element models were firstly developed to repeat the experimental results and then used to carry out parametric studies to generate a numerical data pool. Based on the obtained numerical data, the influences of end distance, edge distance, longitudinal spacing, transverse spacing and sheet thickness on failure loads of austenitic stainless steel thin sheet bolted connections were discussed. The test and numerical data were used to assess the existing design provisions, as given in the European code and American specification. The assessment results revealed that the European code led to overall accurate but scattered failure load predictions, while the American specification was shown to result in overly unsafe and scattered failure load predictions.
Axial splitting and curling behaviour of circular sandwich metal tubes with metal foam core is investigated analytically and experimentally. The sandwich tubes split axially and the strips curl ...outward by prefabricated cracks at the distal end of the specimens. Axial compression experiments of circular sandwich metal tubes are carried out and deformation modes are found. A theoretical model is developed to predict the axial splitting and curling behaviour of the circular sandwich metal tubes including effects of the tearing of the cracks, plastic bending, curling, foam compression and friction. It is shown that the analytical predictions capture the experimental results reasonably. Effects of the tube thickness, foam strength, foam thickness, the number of the prefabricated cracks, and the semi-angle of the die are of vital important in energy absorption devices by the axial splitting and curling of circular sandwich tubes.
Unable to move, plants are physically restrained to the place where they grow. Remarkably, plants have developed a myriad of mechanisms to perceive the surrounding environment in order to maximize ...growth and survival. One of those mechanisms is the ability to perceive mechanical stimulus such as touch (thigmomorphogenesis), in order to adjust growth patterns (in different organs) to either attach to or surround an object. Roots are able to perceive several mechanical forces (e.g., gravity, touch). However, being the "hidden part" of a plant, it is difficult to assess their response to mechanical stimulation. In this chapter, our team presents a simple method to evaluate rice (Oryza sativa L.) root mechanosensing response that can be used to test different conditions (e.g., hormones) affecting rice root response to touch stimulus. This method is affordable to any lab and can be upgraded with a fully automated image recording system. We provide a detailed protocol with several notes for a more comprehensive application.
Ultra-high performance concrete (UHPC) can be a good candidate for bridge deck overlay or repair materials of structural members due to its superior mechanical properties or durability. However, ...large autogenous shrinkage characterized by UHPC may be an obstacle to extending its applications. A novel internal curing (IC) agent, calcined bauxite (CB) aggregate, has been developed to effectively reduce the autogenous shrinkage of UHPC and meantime enhance its mechanical properties. This study further examines its efficiencies in solving shrinkage issues by restrained ring test and large-scale UHPC-concrete composite slabs. In restrained ring tests, when both no fibers, the IC UHPC matrix with CB aggregate shows smaller crack width (0.25 versus 1.0 mm at 9 d) and delayed (5.2 d versus 3.6 d) onset of cracking than the normal UHPC matrix; when having fibers, the normal UHPC shows micro-cracking while no cracking was detected in IC UHPC even observed at one year. Normal UHPC overlay shows more serious delamination and curling than the IC UHPC overlay, and it also shows a hairline crack on the side surface at midspan. Early-age exposure to drying at 1 d has a detrimental effect by exhibiting the most severe delamination and curling of the UHPC overlay, and reinforcement in UHPC layer is effective in reducing its shrinkage strain.
•A novel internal curing agent, calcined bauxite (CB) aggregate, was used to check its efficiency in solving shrinkage problem of UHPC.•The internally-cured UHPC matrix with CB aggregate shows smaller and delayed onset of cracking than normal UHPC matrix (both no fiber) in restrained ring test.•Normal UHPC overlay shows more serious delamination and curling than internally-cured UHPC overlay caused by excessive shrinkage in UHPC.
Desiccation-induced curling of mud layers on the earth surface is a ubiquitous natural phenomenon, as a result of mud-atmosphere interaction. Field observations reveal that the curling behaviors of ...muds were closely related to the overlying layer thickness and the basal layer condition. In order to interpret field observations, laboratory experiments were conducted on ten remolded mud samples with varying overlying layer thicknesses and basal conditions. Experimental results are consistent with field observations and provide insights into the dynamic mud curling process. During drying, the mud curling is driven by the shrinkage strain gradient along the mud profile. For a thin overlying mud layer, the mud curling is unidirectional, either upward (∪) or downward (∩), depending on the basal condition. For a thick overlying layer, the mud begins with upward curling and then recovers. Increasing the layer thickness not only weakens the mud curling but also improves the curling recovery capacity. Furthermore, under a stratified structure, the overlying mud curling is significantly influenced by the interplay of the capillary and friction forces developed at the mud undersurface. Both factors are strongly associated with the basal particle size. The decreasing basal layer particle size smoothens the interface, probably causing the unidirectional downward curling of the overlying layer. However, a rougher basal layer may induce that the overlying mud curls initially at a higher water content and undergoes a more noticeable upward curling. Through field observations and experimental tests, this study is expected to advance the current understanding of various mud curling processes.
•A thin overlying mud curls unidirectionally, either upwards (on a rough base) or downwards (on a smooth base).•Thickening the overlying layer reduces the curling potential and improves the curling recovery capacity.•Interfacial capillary force between overlying and basal layers restraints the separation of both layers.•Increasing basal particle size intensifies interfacial frictional force to promote the upward curling.
The sport of curling is played on an ice surface with raised ice pebbles and uses curling rocks made of granite. The effect of sweeping is thought to straighten the rock’s projected curved path and ...increase the distance travelled. Recent anecdotes suggest that sweeping from the center of the running surface with the direction of rotation and curl is thought to increase the amount of curl, whereas sweeping against and opposite the curl is thought to decrease the amount of curl. The purpose of this study is to observe the topography of the ice surface while comparing scratch measurements from different broom materials. Nine conditions were replicated: nipped pebble, rock traversing the ice, and seven broom conditions. Replicas of the ice were created with vinyl polysiloxane and observed with an optical microscope. Roughness profiles of the replicas were measured, and broom materials were compared using data from an optical profiler.
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