Stainless Steel Grid Research Articles

Growth region characterization of carbon nanotubes synthesis in heterogeneous flame environment with wire-based macro-image analysis

Identification of carbon nanotube (CNT) growth region is paramount in a heterogeneous environment of flame to ensure an improved yield and growth rate. Previously, the growth region analysis in flame synthesis has been done based on repetitive scanning electron microscope (SEM) characterization that tends to be costly and time-consuming for a large heterogeneous environment. A systematic evaluation of the experimental method for growth region characterization is very limited. Therefore, the present study provides a detailed sensitivity and accuracy evaluation of a simple wire-based macro-image analysis (WMA) method for the measurement of steady-state and temporal change of growth region size for multiwalled carbon nanotubes (MWCNT) in a methane diffusion flame with varied air flow rate at atmospheric condition. The WMA method was developed to simplify the MWCNT deposit region identification using the image produced by digital single-lens reflex (DSLR) camera and post-processed using baseline data that was gathered through a one-time SEM analysis. Pure nickel wire was positioned in the flame with a stainless-steel wire grid placed on top of the substrate wire to redistribute the flow field. The MWCNT deposit region that is confined in the fuel-rich region at the inner side of the flame sheet shifts toward the flame centerline with the increase of the air flow rate from 1 to 10 slpm due to the shift of the flame sheet in the same direction. The inception and growth of MWCNT are consistently observed together with the formation of amorphous carbon layer, which has been verified based on detailed SEM analysis. The formation of amorphous carbon layer happens due to the higher rate of carbon supply compared to that of the carbon diffusion rate in nickel catalyst for CNT growth. These phenomena serve as the fundamental basis of the present WMA method. At 10 mm above the burner, the WMA method at steady state successfully detected the change in size and spatial distribution of deposit region by a factor of 2.28 and 2.68 respectively at varying air flow rate with ± 0.5 mm accuracy. The present method demonstrated high sensitivity to capture the temporal change of the deposit region length within the exposure time for the growth rate measurement of the deposit region. More than twofold increase in effective growth rate was successfully captured at a high air flow rate due to the change in equivalence ratio from rich to stoichiometry that promotes the increase in heat release rate. The present flame setup was able to produce a widest CNT deposit region with an optimum growth rate at 6 slpm air flow rate. High-resolution transmission electron microscopy (HRTEM) analysis verified that the synthesized CNT is hollow with multiwalled internal structure and Raman spectroscopy analysis indicated that crystallinity level of the produced MWCNT is relatively constant with the change in air flow rate.

Combination of potential nanomaterials for intermediate temperature oxygen membranes on the base of δ-Bi2O3/Ag

The new architecture of IT thin oxygen membranes on a flexible support made of stainless steel grid is proposed. This membrane is designed to realize clean coal energy with combustion of pulverized low ranked solid fuels in oxygen enriched atmosphere using purified flue gases as a sweep gas. Multilayer membrane with thickness about 40 μm is consist of metal grid with deposited protected layer and filled by porous agglomerates of e-conducting perovskite, dense selective layer on the base of multilevel nanocermet δ-Bi2O3/Ag, protected porous layer and supported Pd/Pt-catalyst layer. Mechanochemical ceramic method is the main approach to designing of nanomaterials with interpenetrating and core-shell microstructures. Compatible combination of materials and operations is determined for creating oxygen membranes with operating temperature 500-550 °C. The best combination of materials successfully passed the degradation test at 500 °C for 500 hours.

Pilot⁻Scale Production of Carbon Hollow Fiber Membranes from Regenerated Cellulose Precursor-Part II: Carbonization Procedure.

The simultaneous carbonization of thousands of fibers in a horizontal furnace may result in fused fibers if carbonization residuals (tars) are not removed fast enough. The optimized purge gas flow rate and a small degree angle in the furnace position may enhance the yield of high quality carbon fibers up to 97% by removing by-products. The production process for several thousand carbon fibers in a single batch is reported. The aim was developing a pilot-scale system to produce carbon membranes. Cellulose-acetate fibers were transformed into regenerated cellulose through a de-acetylation process and the fibers were carbonized in a horizontally oriented three-zone furnace. Quartz tubes and perforated stainless steel grids were used to carbonize up to 4000 (160 cm long) fibers in a single batch. The number of fused fibers could be significantly reduced by replacing the quartz tubes with perforated grids. It was further found that improved purge gas flow distribution in the furnace positioned at a 4-degree to 6-degree angle permitted residuals to flow downward into the tar collection chamber. In total, 390 spun-batches of fibers were carbonized. Each grid contained 2000–4000 individual fibers and these fibers comprised four to six spun-batches of vertically dried fibers. Gas permeation properties were investigated for the carbon fibers.

Electrocodeposition method to synthesize low‐cost cathodes based on inert carriers for bioenergy production and wastewater treatment in microbial fuel cells

In this work, platinum‐free based cathodes are investigated for their application in microbial fuel cells (MFCs). Carbon cloth and stainless steel grid were employed as different supporting materials for the electrodeposition of three types of inert carriers, for example, clay, silica, and aluminum‐nickel alloy, all of them combined with nickel. This work evaluates the potential of this technique in order to elaborate active MFC cathodes. The voltammograms obtained confirm both the reduction of protons, with the adsorption of hydrogen from −0.5 to −1.8 V, and the oxidation of water, producing sufficient current intensity to reduce oxygen. Among the options investigated, cathodes based on aluminum‐nickel alloy/nickel achieved the highest catalytic activity, being carbon cloth the most suitable supporting material. Thus, aluminum‐nickel alloy/nickel electrocodeposited onto carbon cloth exhibited the highest levels of power output (150 mW.m−3) when tested in MFCs fed with wastewater. This type of low cost cathodes also offers promising results for wastewater treatment reaching up to 90% of chemical oxygen demand removal. © 2018 American Institute of Chemical Engineers Environ Prog, 38:e13083, 2019

Cobalt hydroxide hexagonal nanoplates anchored on functionalized carbon nanotubes (CNTs) for supercapacitor applications: one-pot electrochemical fabrication of high performance nanocomposite

β-Co(OH)2/CNTs nanocomposite was prepared through a facile electrodeposition method onto stainless steel grid, and its charge storage capacity in supercapacitor applications was studied. The co-deposition of cobalt hydroxide/CNTs was carried out, for the first time, from a CNTs–COOH dispersed aqueous electrolyte containing 0.005M CoCl2. The simple deposition parameters were used, which included direct current mode (10 mA cm−2) at RT conditions. The characterization techniques of XRD, IR, FE-SEM, BET and TEM proved the deposition of crystalline β-Co(OH)2 hexagonal nanoplates grown onto electrophoretically deposited CNTs on the cathode surface. BET test indicated that the high surface area of 144.8 m2 g−1 with micro-porous surface for the fabricated composite. The GCD tests showed excellent charge storage behavior with delivering specific capacitances as high as 1287 F g−1 (0.5 A g−1), 1124 F g−1 (1 A g−1), 956 F g−1 (2 A g−1), 834 F g−1 (3 A g−1), 712 F g−1 (5 A g−1) and 573 F g−1 (10 A g−1) and capacity decay of 10.6% during 5000 cycles.

Analysis of grid electrode assisted plasma based ion implantation system and application to ion beam assisted deposition for insulator substrates

A grid electrode assisted plasma based ion implantation system, which was originally designed only for ion implantation on insulator substrates, was investigated as a system of sputter deposition with high energy ion beam irradiation. When pulses of negative high voltage were applied to grid electrodes immersed in argon plasmas, high energy ions were observed to bombard the surface of the grid electrodes during the rise and plateau times of the pulses, using particle-in-cell (PIC) simulations. The resulting sputter deposition of atoms on the substrate from the stainless steel grid electrodes was confirmed by X-ray photoelectron spectroscopy. During the fall time of the pulses, PIC simulations indicated high energy ion beams of pseudowaves bombarded the surface of the substrate. Thus we verified that by using grid electrodes, ion beams can irradiate the insulator substrate after the sputter deposition within the time scale of a single pulse. In the proposed configuration, problems due to high voltage on insulator can be avoided because the insulator substrates float in plasmas for the entire process. Finally, we discuss potential application of the system for ion beam assisted deposition as a compact plasma based ion implantation and deposition system, which does not require a separate sputtering system.

Metallic wire grid behavior and testing in a low pressure gaseous noble elements detector

High voltage performance has been a challenge for noble element detectors. One piece of this challenge is the emission of electrons from metal electrodes when applying high voltage. This has become a major concern for low-background detectors such as LUX-ZEPLIN (LZ). LZ is a liquid xenon Time Projection Chamber (TPC) searching for Weakly Interactive Massive Particles (WIMPs). In this work, we demonstrate a method to measure electron emission from metallic electrode grids via detection of proportional scintillation light. We find consistency with Fowler-Nordheim emission with a surface parameter β = 1988 after electro-polishing treatment of a stainless steel grid.

Merging Electrochemistry and Water Capillary Condensation to Understand the Corrosion Mechanism of Steel in Carbonated Concrete

Reinforced concrete is one of the most used man-made materials worldwide, one of its main causes of degradation worldwide is carbonation induced corrosion, accounting every year for billions of dollars for main­tenance, repair and rebuilding. The alkali produced by the Portland cement hydration (mainly Ca(OH)2) allows steel passivation. CO2 from the atmos­phere can enter the concrete pores and react with the Ca(OH)2, leading to a decrease of pH that can propagate to the reinforcement level. In presence of oxygen the steel starts to corrode, the corrosion products precipitate in the surrounding of the reinforcement, generating stresses that can lead to cracking and spalling of the concrete cover. The topic of carbonation induced corrosion is becoming of key importance in the reduction of environmental footprint of Portland cement production, responsible for about 8% of the man-made CO2 and thus for global warming and climatic change. The replacement of Portland cement by using supplementary cementitious materials (SCM) is one of the most viable, short-term solutions. This, however, might impair the durability of reinforced concrete; reducing the Portland cement content leads to a reduced production of calcium hydroxide and therefore to a much faster carbonation process. When the carbonation front reaches the reinforcement before the end of service life, the corrosion propagation becomes an important part of the life of the structure. To be able to collect data of corrosion propagation rates in a reasonable time a new experimental set up has been designed, which consists of small (8x8 cm) and thin (0.6 cm) mortar samples instrumented with a reference electrode (Ag/AgCl), 5 steel wire electrodes and a stainless steel grid counter electrode. The thin sample allows rapid carbonation and equilibration of environmental humidity. Electrical resistivity, oxygen cathodic current, open circuit potential and corrosion rate of the steel can be measured. The results have shown that the corrosion rate increases markedly with increasingly higher relative humidity (up to 99% RH), maximum values around 2 µA/cm2 have been found in wet/dry cycles. Increasing corrosion rate was associated with a decrease of the corrosion potential, the ohmic resistance of the electrochemical cell was found to correlate with the corrosion rate. The oxygen reduction limiting current was always about five to ten times higher than the corrosion rate. The influence of cement type and water/binder ratio was of minor importance. The mechanism of corrosion of steel in carbonated concrete is under debate since 1980 - and after almost 40 years there is still no agreement. The traditionally proposed controlling mechanisms such as resistive, cathodic or anodic control have been found not suitable for corrosion of steel in carbonated mortar, which has always been considered as a uniform process. Instead, being the cement paste a porous system, the capillary water condensation had to be taken into account. With the Kelvin equation and the porosity curves, the volumetric water content could be calculated for every different sample and relative humidity condition. A correlation between the water content and the corrosion rate was found. Merging electrochemistry and water capillary condensation theory allowed explaining the mechanism of corrosion of carbon steel embedded in a porous system. The porosity and degree of pore saturation define the electrochemically active area with respect to the total steel surface. This active area varies by orders of magnitude depending on the exposure condition: from immersed conditions to 99% RH the active area goes down to ca. 40 %, at 80% RH only 1 %. The volumetric water content also determines the available diffusion volume of produced Fe2+ ions, which modifies the anodic reaction reversible potential. A larger diffusion volume leads to a lower Fe2+ concentration and therefore lower reversible potential and higher corrosion current according to the Evans diagram. The two contributions can be recognized and the huge variation of the corrosion rate with the exposure condition can thus be explained. In conclusion the corrosion mechanism of carbon steel in carbonated concrete could be determined and the corrosion rate can be uniformly expressed, for every different humidity state, water to binder ratio and binder type, as a function of pore solution pH, water content and porosity. Figure 1

Developing improved tissue-engineered buccal mucosa grafts for urethral reconstruction.

We aimed to compare alternative synthetic scaffolds suitable for future implantation and to examine the use of an inhibitor of lysyl oxidase (beta-amino-propionitrile [β-APN]) to reduce contraction in these implants. Three synthetic scaffolds were compared to natural dermis as substrates for the production of tissue-engineered skin. For natural dermis, Euroskin was used to provide a cell-free cadaveric dermis. Synthetic scaffolds consisted of microfibrous poly-L-lactic acid (PLA), nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and a micro-/nanofibrous trilayer of PLA-PHBV-PLA. The latter were all electrospun and then all four scaffolds (three synthetic, one natural) were placed in six well plates. A culture well was formed on the scaffold using a 1 cm diameter stainless steel ring and 1.5×105 oral fibroblasts were seeded one side; after two days of culture, the ring was placed on the other side of the scaffolds and 3×105 oral keratinocytes were seeded on to the scaffolds and cultured with keratinocytes uppermost. After a further two days of culture, scaffolds were cut to 1 cm2 and raised to an air-liquid interface on stainless steel grids; some were treated with 200 μg/mL β-APN throughout the culture period (28 days). Contraction in vitro was assessed by serial digital photography of cell-seeded scaffolds and cell-free scaffolds three times a week for 28 days. All cell-seeded scaffolds were assessed for cell metabolic activity, mechanical properties, histology, and morphology by scanning electron microscopy (SEM). The mean fibre diameters and pore sizes of PLA and PHBV scaffolds were 2.4±0.77, 0.85±0.21 μm (p<0.001), and 10.8±2.3, 4.3±1.1 μm (p<0.001), respectively. Oral fibroblasts and keratinocytes were tightly adhered and grew well on both surfaces of trilayer. The ultimate tensile strength (UTS) and Young's modulus (YM) of PLA samples were significantly lower than Euroskin (p<0.001 and p<0.05, respectively); only the UTS of the trilayer samples was slightly significantly lower (p<0.05). Metabolic activity was significantly increased for cells on all scaffolds, without significant differences between them from Day 0 to Day 28. There were no adverse effects of β-APN on cell viability. With respect to contraction, cells on trilayer and PHBV monolayers did not undergo any significant contraction; however, cells on PLA monolayer and Euroskin contracted 25.3% and 56.4%, respectively, over 28 days. The addition of 200 μg/ml β-APN significantly reduced contraction of Euroskin compared with the control (p<0.01); however, β-APN did not affect PLA contraction during this culture period (p>0.05). This study shows that a trilayer micro-nano-3D porous synthetic scaffold is suitable for oral keratinocyte and fibroblast growth with good cell viability and minimal contraction. This material also has good mechanical properties and histological analyses showed its ability to mimic normal human oral mucosal morphology. Furthermore, synthetic trilayer scaffolds have advantages over biological scaffolds - there is no risk of disease transmission or immunological rejection and they appear resistant to contraction. We suggest they present a good alternative to allodermis for future use in urethral reconstruction.

A gas-discharge plasma focuser

A device is proposed for the formation of a gas-discharge plasma stream with a sinusoidal distribution of the charged-particle density over the stream cross section, which is achieved by using wavy shapes of the anode and cathode surfaces that are placed coaxially relative to each other at the distance λ e < h < 3λ e , where λ e is the mean free path of an electron in the gas-discharge plasma stream. The anode is a stainless steel grid with mesh dimensions of 1 × 1 mm. The aluminum cathode is 120 mm in diameter and 50-mm thick. The device provides a discharge current of up to 0.6 А at a controlled voltage at the electrodes in the range of 0.21–0.7 kV. In this case, plasma streams propagate to a distance of up to 50λ e beyond the limits of the electrodes.

Ein In-vitro-Mausmodell für die Palatogenese und die Entstehung von Gaumenspalten

AbstractThe mouse is an excellent model to study palatogenesis since, like humans, it is a mammal, it can easily be bred and a wide array of molecular tools are available. Moreover, the isolated embryonic mouse palate can be cultured in vitro, which allows us to study the actual fusion process in detail.Just prior to the actual fusion at E13, the maxilla with the 2 palatal shelves can be dissected from the embryo head. The maxilla is cultured on a filter paper on top of a stainless-steel grid at the interface of the culture medium and air. After 24 h in culture, the palatal shelves are in contact and the MES is clearly visible. At 48 h, the MES has nearly completely disintegrated with small remnants at the nasal and oral side of the palate. Finally, at 72 h, the palatal shelves are completely fused and osteoid tissue is beginning to form in the lateral areas.The exact downstream molecular mechanisms that lead to clefting are far from being unraveled. The model for palate fusion presented here offers the possibility to analyze the molecular and cellular mechanisms that lead to clefting as a result of specific genetic and environmental factors. This will pave the way to pharmacological intervention for the prevention of cleft lip and/or palate in susceptible individuals.

Formation of catalytically active layers on the surface of polymetallic alloys

A new method for the synthesis of catalysts on polymetallic supports via the formation of intermetallic (aluminide) layer on the support surface followed by leaching and stabilization of the layer has been proposed. The intermetallic layer structure and distribution of elements in the layer were studied by scanning electron microscope considering a nickel chromium stainless-steel grid as an example. The morphology and elemental composition of the active phase on the catalyst surface were studied. The complex structure of this phase was found to consist of two types of entities with different composition located on the continuous highly porous substrate. The catalyst sample was tested in deep oxidation of CO and propane and demonstrated high activity. The developed method can be used to obtain new high-performance polymetallic catalysts.

Conceptual design of Dump resistor for Superconducting CS of SST-1

Under upgradation activities for SST-1, the existing resistive central solenoid (CS) coil will be replaced with Nb3Sn based superconducting coil. Design of Central solenoid had been completed and some of the initiative has already taken for its manufacturing. The superconducting CS will store upto 3 MJ of magnetic energy per operation cycle with operating current upto 14 kA. During quench, energy stored in the coils has to be extracted rapidly with a time constant of 1.5 s by inserting a 20 mΩ dump resistor in series with the superconducting CS which is normally shorted by circuit breakers. As a critical part of the superconducting CS quench protection system, a conceptual design of the 20 mΩ dump resistor has been proposed. The required design aspects and a dimensional layout of the dump resistor for the new superconducting CS has been presented and discussed. The basic structure of the proposed dump resistor comprises of stainless steel grids connected in series in the form of meander to minimize the stray inductance and increase the surface area for cooling. Such an array of grids connected in series and parallel will cater to the electrical as well as thermal parameters. It will be cooled by natural convection. During operation, the estimated maximum temperature of the proposed dump resistor will raise upto 600 K.

Role of iron and chromium in the photocatalytic activity of titanium dioxide films on stainless steel

Photocatalytically active titanium dioxide films have been formed on stainless steel grids via sol–gel process followed by heat treatment in the temperature range of 450–550°C. During UV irradiation of the films in an aqueous solution of the Rhodamine B dye and in distilled water we have detected iron and chromium dissolution from uncoated grid regions and the deposition of iron and chromium compounds onto the titanium dioxide surface. The deposition rate of these compounds increases with annealing temperature, which leads to a decrease in the photocatalytic activity of the films.

Use of a Disposable Self-adhesive Grid for Accurate Microimplant Placement

ABSTRACTMicroimplants have ushered in the concept of absolute anchorage by intraoral means with the added benefit of being completely operator dependent. These factors ensure efficient anchorage control. However, these benefits come at the cost of precise placement considering the proximity of anatomically significant structures. It is of utmost importance to avoid damage to roots in case of interradicular placement. In order to overcome this difficulty, the following case report describes an innovative grid-guide template with an anti-inflammatory adhesive backing for accurate and easy microimplant placement. The assembly consists of a stainless steel grid mesh stuck on a micropore surgical tape with trioplast dental paste on the tissue-facing surface. It is an accurate, efficient, economical, and easy method of microimplant placement.How to cite this articleJadhav BS, Patni V, Pawar P. Use of a Disposable Self-adhesive Grid for Accurate Microimplant Placement. J Contemp Dent 2017;7(3):161-165.

Large area growth of ZnO nanorod arrays on the stainless steel grid by aqueous solutions

Large-area ZnO nanorod arrays have been synthesised on a stainless steel grid by two-step growth approach, including the synthesis of seed layer and growth of ZnO nanorods in aqueous solution. X-ray diffraction analysis and energy dispersive X-ray elemental mapping measurements indicate wurtzite ZnO structures are formed. Scanning electron microscopy shows high uniform coverage of the densely packed ZnO nanorod arrays are grown on the stainless steel grid frame, and the as-grown ZnO nanorods have uniform diameters. Meanwhile, the ZnO nanostructures also show good optical quality and photocatalytic activity. The results show using the stainless steel grid as substrate will provide a promising way of producing large-scale nanorod arrays with good controllability and morphologies. And it will be critical in potential application such as high-efficiency filtering and catalysts.

New wood-based panel with imprinted 3D surface pattern and improved internal bonding

This research is on a new development towards three-dimensional surfaces for wood-based panels, i.e., particleboards (PB). By imprinting a self-designed stainless steel grid on both sides of PB the following research questions were investigated: (1) feasability of the 3D-pattern imprintment during hotpressing of resinated PB furnishes, (2) assessment of mechanical properties of imprinted PB, and (3) finite element modelling to understand and optimize material properties, including veneer-added sandwich panels. Following a factorial experimental design PB were produced in the laboratory and cut specimens were tested according to standards. As a result, the 3D-pattern imprintment resulted in a much higher internal bonding: For the 500 kg/m3 PB the IB increase was 35 %, while for the 700 kg/m3 the increase was even 67 %. The vertical density profile showed a roof-like shape, with a high density level in the core layer. Bending strength and stiffness turned out to be much lower than for the control. Through finite element modeling (FEM) these property changes could be mechanically explained. A successful compensation for the reduced bending performance could be demonstrated through two-side veneer sheet additions. FEM is also shown to be instrumental for the property optimization of the 3D-pattern imprinted PB. Since IB has significantly increased, the overall PB density could be reduced, meaning a light panel is required for the same product performance. The new 3D-pattern imprinted PB also constitutes a decorative design feature, which could lead to various product applications. Since the imprintment process is easy to execute, this new PB product option might be easily adopted by industry.

Characterization of H2S gas sensor based on CuFe2O4 nanoparticles

Copper ferrite (CuFe2O4) nanoparticles were prepared by the sol-gel auto-combustion method and used to construct a conductometric gas sensor in this work. The as-prepared CuFe2O4 nanoparticles were annealed at 500 °C and 750 °C. X-ray diffraction measurements as well as transmission electron microscopy were used to identify the crystal structure of as-prepared and annealed nanoparticles. The results reveal growth of nanoparticle size crystal structure as well as phase transition from cubic structure to tetragonal symmetry upon annealing. Fourier Transform Infra-Red Spectroscopy (FTIR) measurements of the CuFe2O4 nanoparticles revealed the tetrahedral and octahedral absorption bands that are characteristic of the spinel ferrite. Nanoparticle powder was pressed in a form of a pellet to form the gas sensor device. The pellet was placed between a copper sheet and a stainless steel grid for the bottom and top electrodes, respectively. The results revealed that the produced CuFe2O4 nanoparticles are sensitive to both H2S and H2, but with higher sensitivity to H2S at low temperatures. The gas sensitivity of the sensors could be investigated in terms of the large number of reactive surface sites due to the large surface area of the nanoparticles as well as the adsorption of oxygen species on the surface of nanoparticles.

Selective H2S sensor based on CuO nanoparticles embedded in organic membranes

We report on H2S gas sensors based on CuO nanoparticles that are embedded within polymer membranes of poly-vinyl-alcohol (PVA) and glycerol ionic liquid (IL). The nanoparticles were fabricated by the colloid microwave assisted hydrothermal method that enables a precise control of nanoparticle size. Polymer solutions of PVA and 5% IL were prepared with different concentrations of nanoparticles. Next, the solutions were used to fabricate polymer membranes by the solution casting method. The produced membranes were flexible and they hold semiconducting properties. Each membrane was encapsulated between two electrical electrodes where the top and bottom electrodes were made of stainless steel grid and copper sheet, respectively. A constant voltage was applied across the electrodes, and the electrical current response signal was measured. The measurements revealed that those sensors were sensitive to H2S gas with concentrations as low as 10ppm, and they functioned at low temperatures. In addition, their sensing behavior was reversible which enabled repeatable use of those sensors. Those sensors were also selective to H2S, and they exhibited fast response of 20.4±12.8s. Moreover, the sensors were easy to manufacture, thus, they have potential to be used for practical field applications.

Stainless Steel Grids for Confinement of Clay Brick Masonry Columns

AbstractThis work presents the results of an experimental investigation on the behavior of 21 solid clay brick columns internally strengthened by stainless steel grids placed in the horizontal joints of mortar. This reinforcing technique can be applied as a constructive technique for new construction or as a retrofitting technique for existing structures (old structures to be reconstructed by original constructive method and internal reinforcement). Monotonic compressive loading tests were carried out under concentric and eccentric load. The effects of different numbers of steel grids and eccentricity of the external load were examined. Also, a detailed characterization of the constituent materials was made experimentally. The compression tests show the effectiveness of the proposed strengthening technique, which proves to be able to produce the increases in strength and energy required to collapse brick columns under both concentric and eccentric loads. To provide an analysis method for practical applica...