Weld Mesh Research Articles

Structural Behaviour of Ferrogeopolymer Slabs under Flexure

The main objective of this paper was to present the results of experimental investigation carried out to study the structural behaviour of ferrogeopolymer elements under flexure. Initially the properties of geopolymeric binder prepared using the source materials such as Fly ash and Ground Granulated Blast Furnace Slag (GGBS) without conventional cement have been investigated. The different parameters considered in this study are the ratio of binder to fine aggregate (1:2 and1:3) and the ratio of Na2SiO3 to NaOH solutions (2.0 and 2.5). The various combinations of Fly ash and GGBS considered are 90% & 10% and 80% & 20%. The alkaline liquid to binder ratio is fixed as 0.45. The individual properties of mortar such as Compressive Strength and Density were determined as per relevant Indian standards. The geopolymer concrete mix that gives the highest compressive strength was used to cast the ferrogeopolymer structural slabs. Four numbers of rectangular slabs of size 800 mm x 300 mm x 25 mm were prepared with two types of meshes such as mild steel and galvanized iron weld mesh with single and double layers. Based on the test results Load-Deflection curves were drawn and the effectiveness of mild steel and galvanized iron weld meshes was compared from the characteristics such as first crack load, ultimate load, energy absorption and ductility.

Behavior Of Reinforced Concrete T. Beams With Welded Mesh Reinforcement Under Repeated Load

Behavior Of Reinforced Concrete T. Beams With Welded Mesh Reinforcement Under Repeated Load

Impact strength of Hybrid Steel Mesh-and-Fiber Reinforced Cementitious Composites

Large volumes of concrete are produced for construction purposes which creates sustainability issues. Therefore, some of the alternatives to concrete that are being researched and implemented are Steel Mesh Reinforced Cementitious Composites (SMRCC) and Fiber Reinforced Cementitious Composites (FRCC). But due to limitations in element thickness and volume percentage of reinforcement in SMRCC and FRCC, this study has made an attempt to develop Hybrid Steel Mesh-and-Fiber Reinforced Cementitious Composites (HSMFRCC) and study its impact performance. Thus, in order to evaluate the energy absorption of HSMFRCC, 250 mm × 250 mm × 25 mm (thick) slab elements were cast with various combinations of 3–5 layers of steel weld mesh and SS fibers of 0.5–2.5% (of volume of specimens) and low velocity repeated drop weight impact test was administered. From the experimental results, it was found that the impact resistance of HSMFRCC (test specimens) is higher than SMRCC (control specimens using only steel mesh as reinforcement). Regression models have been developed in this study and validated using new hybrid mesh and fiber reinforcement mix. The predicted regression equations developed for initial and ultimate impact energy absorption of cementitious composites with hybrid steel mesh and fibers will be quite useful to the practitioners.

Animal management in the Australian rangelands

Invasive vertebrates and overabundant native species cause significant economic and environmental damage in the Australian rangelands, which cover more than 70% of the continent. Some estimates put the annual loss in livestock production due to such pest species at more than $700 million.1–3 Access to pastoral watering points has been a major factor in the spread and survival of pest species. While methods of controlling access watering points have been developed,4 they are problematic. Essentially all current trap systems rely on oneway barriers and cannot discriminate between pest and desired species. To address this problem, we have developed a system of identifying animal species using machine vision, which uses computers to process images and then applies the resultant information to manipulate equipment. In recent years such systems have becomemore common in remote-sensing applications for all aspects of the agricultural domain5 as well as many areas of wildlife management.6 When used in conjunction with an enclosure and an automated gate, our system can control animals’ access to a limiting resource, like water,7 and thus function to exclude pest species, trap desired species, and otherwise manage livestock. It requires no physical contact with the animals, reducing both system maintenance requirements and animal stress. Computing capabilities have now developed to the point that processing of real-time video data is also feasible. The concept that governs the system is simple: control the water (or other resource), and you control all large vertebrates (>10 kg) that require water to survive. Three main components achieve this goal. First, an enclosure with an entry lane surrounds the limiting resource. For the machine vision software to accurately identify animals to the species level, it must view the animals laterally and in single-file arrangement. Our enclosure and entry lane were constructed of galvanized weld mesh Figure 1. A watering point enclosure excludes some species while allowing access to others. The gate remains open, closing when undesirable animals are detected in the entry lane, then reopening after a predetermined period of time.

Behaviour of concrete floor slabs at ambient and elevated temperatures

This paper presents the latest developments of a simple design method used to predict the membrane action of unrestrained concrete, or concrete and steel composite, floors under fire conditions. The developments include the refinement of the assumed in-plane stress pattern and a prediction of when concrete crushing occurs in the proximity of the corners of the slab. The design method is compared against 44 small-scale tests carried out at ambient and elevated temperatures on horizontally unrestrained slabs with an aspect ratio of 1.0 or 1.55. The slabs were reinforced with either mild steel or stainless-steel welded mesh of different grades, ductility, sizes and bar spacing. Both the ambient and fire tests highlighted the occurrence of membrane action, either supporting loads higher than the theoretical yield-line load in the case of the ambient tests, or reaching higher failure temperatures compared to those calculated based on yield-line theory. Comparison between the developed simple design approach and test results showed good correlation both at ambient and elevated temperatures.