Block Shear Capacity of Bolted Connections in Cold-Reduced Steel Sheets

This paper examines the mechanisms for block shear failures of bolted connections in steel plates postulated in the design equations specified in the North American, European and Australian steel structures codes. It explains that there is only one feasible mechanism for the limit state of conventional block shear failure, that which involves tensile rupture and shear yielding, irrespective of the steel material ductility. It describes the fundamental shortcomings of various code equations for determining the block shear capacity of a bolted connection. Based on the tensile rupture and shear yielding mechanism, an in-plane shear lag factor, and the active shear resistance planes identified in the present work, this paper proposes a rational equation that is demonstrated to provide more accurate results compared to all the code equations in predicting the block shear capacities of bolted connections in G450 steel sheets subjected to concentric loading. The resistance factor of 0.8 for the proposed equation is computed with respect to the LRFD approach given in the North American specification for the design of cold-formed steel structures

Some chemical, physical and sensory properties of soda crackers supplemented with tomato seed

In this study, the potential use of tomato paste waste material tomato seed in crackers was studied. Thus, it was studied to determine the usability of tomato seeds which were known as rich in active food ingredients in human nutrition. During the production of cracker, wheat flour was partially (2%, 4% and 6%) substituted with tomato seed meal. In the study, it was found that substitution of tomato seed meal into wheat flour caused a significant (p0.05) increase in protein, oil, ash, soluble, insoluble and total dietary fiber contents, minerals (Mg, Ca, P, Mn, Fe), total phenolics and antioxidant capacity values. Cracker samples having tomato seed had significantly different (p0.05) L and a values, and similar (p>0.05) b values with control crackers. Color, flavor and crispiness values of all crackers were similar in sensory evaluation. But crackers having 6% of tomato seed meal received significantly (p0.05) lower scores in flavor and overall acceptability

Some chemical, physical and sensory properties of soda crackers supplemented with tomato seed

In this study, the potential use of tomato paste waste material tomato seed in crackers was studied. Thus, it was studied to determine the usability of tomato seeds which were known as rich in active food ingredients in human nutrition. During the production of cracker, wheat flour was partially (2%, 4% and 6%) substituted with tomato seed meal. In the study, it was found that substitution of tomato seed meal into wheat flour caused a significant (p0.05) b values with control crackers. Color, flavor and crispiness values of all crackers were similar in sensory evaluation. But crackers having 6% of tomato seed meal received significantly (p<0.05) lower scores in flavor and overall acceptability

Replaceable links with gusseted brace joints for eccentrically braced frames

Various replaceable link details were developed for use in steel eccentrically braced frames (EBFs) during the past decade. These details include but are not limited to bolted flush end-plated links, bolted extended end-plated links, web connected replaceable links, and bolted flange- and web-spliced links. Another detail which is based on splicing the beam outside the link and braces was recently proposed by the authors. The performance of this detail when used with directly connected braces was studied through experimental testing and acceptable performance was demonstrated. In practice gusseted attachments are widely used for connecting the braces to the beams in EBF systems. In this paper, the proposed detail by the authors is extended to replaceable links with gusseted brace attachments. The use of gusset plates enables to tailor the geometry of the replaceable link and allows different details to be developed. Three replaceable link details are proposed herein. The first detail employs standard gusset plated detail where splicing the beam is performed outside the connection region. The second detail develops a more compact replaceable link by connecting the beam to the link within the brace connection panel. The third detail is a pin connected detail where minimal amounts of bending moments are transferred to the brace member. The proposed details are studied by conducting nine nearly full-scale EBF tests under quasi static loading. The type of replaceable link, link length ratio, connection type, gap size of splice connections, demand-to-capacity ratio of members are considered as the prime variables. The inelastic rotation capacity provided by the replaceable links satisfied the requirements of the AISC Seismic Provisions for Structural Steel Buildings (AISC341-16). The links failed mainly due to fracture of the link web or flange. No failures were observed in the gusseted joints demonstrating the potential of the proposed details. © 2018 Elsevier Lt

Hydrometallurgical processing of nontronite type lateritic nickel ores by MHP process

The research work presented in this paper determined the optimum conditions at which nickel and cobalt could be obtained at maximum efficiency from the column leach liquor of the lateritic nickel ore existing in Gordes region of Manisa in Turkey by performing effective hydrometallurgical methods. This column leach solution was initially neutralized and purified from its basic impurities by a two-stage iron removal process, nickel and cobalt were precipitated in the form of mixed hydroxide precipitate from the purified leach solution by a two-stage precipitation method called "MHP" and a manganese removal process was performed at the optimum conditions determined experimentally. By decreasing manganese concentration with this process to an acceptable level yielding at most 10% Mn in hydroxide precipitate, it was possible to produce a qualified MHP product suitable to the current marketing and standard conditions. The experiments conducted showed that by maintaining recycle leaching with sulfuric acid at which 95% of Ni-Co could be recovered from the precipitates, about 81% of Ni and 63% of Co in the lateritic nickel ore (9.72 kg Ni/ton of ore and 0.28 kg Co/ton of ore) could be extracted as mixed hydroxide precipitate by MHP process

Evaluation of seismic response factors for BRBFs using FEMA P695 methodology

This paper reports the details of a numerical study undertaken to evaluate seismic response factors for steel buckling-restrained braced frames (BRBFs) using the FEMA P695 methodology. In the United States, BRBFs are designed according to Minimum Design Loads for Buildings and Other Structures (ASCE 7) and the Seismic Provisions for Structural Steel Buildings (AISC 341). Twenty-four archetypes were designed according to the U.S. specifications and their behavior was assessed by making use of non-simulated collapse models. The interstory drift, brace axial strain and cumulative brace axial strain demands under collapse level ground motions were determined. The results obtained indicate that the current seismic response factors are adequate in terms of interstory drift and cumulative axial strain demands. On the other hand, large differences between the design level and collapse level axial strains were reported, which can result in undesirable brace behavior. Modified approaches were developed to estimate the axial strains for collapse level ground motions. These include a modification to the deflection amplification factor and a modification to the AISC 341 requirements for expected brace deformations. The archetypes were redesigned using the proposed modifications and reevaluated using the FEMA P695 methodology. The results indicate that the proposed modifications result in axial strain demands that are in close agreement with the calculated demands. © 2018 Elsevier Lt