bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving efficiency in nitrous oxide hospital supply systems to aim towards a carbon neutral NHS Wales
Authors: Nicholson L , Timoney R , Evans R
Published: April 2024

Background: Nitrous oxide (N20) is a greenhouse gas with a global warming potential of 280 times that of carbon dioxide. This project aims to identify potential nitrous leak and reduce the waste of N20 in Glangwili Hospital, a small district general hospital in South Wales. 

Methods: British Oxygen Company (BOC) supplied us with data on how much N20 was supplied to, and returned from, the hospital between 2021-2022. Data was collected from the anaesthetic machines over a period of three months, looking at the consumption of N20. A leak test of the piped nitrous system was performed during which no nitrous was used. Lastly, anaesthetists were surveyed on their practice with regards to N20. 

Results: On average, Glangwili purchased 54,000L of N20 per month and consumed 2109L, a usage of 3.9%.  The leak test identified a leak of 1.3L/min. From the survey of local anaesthetists, 80% of respondents state they use N20 only four times a year or less.  

Conclusion: This project has identified that 96% of the N20 purchased does not reach the patient. These findings are consistent with results from Cardiff and Vale University Health board, where a similar project was performed, and other audits across the United Kingdom. These results should encourage other health boards, including smaller hospitals, to investigate the efficiency of their N20 supply, as significant gains could be made in our steps towards carbon neutrality.
How can the Charter for 21st century literacies support technology-mediated teaching and learning?
Authors: Seguna Omar
Published: April 2024

This work presents a critical review of pedagogical practices regarding the use of technologies. Hence, the practices that can make a positive contribution to children’s literacy learning are identified. The study sets out to explore the pedagogical strategies that can be applied through the use of portable devices and other technologies in teaching and learning. It draws on an empirical study in two classrooms of a Maltese state school that I conducted between February and June 2016. The key findings indicated a number of pedagogical affordances which promoted multiliteracies, engagement with a range of modes and media, and collaboration. However, the study also identified that some areas were less well developed, such as the use of playful pedagogies, innovation and experimentation, and critical thinking. The implications for teacher education in Malta are considered.
Students’ preparedness for distance learning - Gaps identified by MCAST educators
Authors: Muscat Christine
Published: April 2024

This study, conducted during the COVID-19 pandemic, investigated students’ preparedness for distance learning. The main catalyst for the identified gaps derives from Maltese obligatory education being delivered face-to-face. Findings revealed that during online tuition, The Malta College of Arts, Science and Technology (MCAST) foundation and diploma-level students lacked digital literacy. Questionnaires completed by lecturers, who shifted online, divulged four e-competencies and skill categories whereby, in the metacognitive segment, these students lack learning style, self-direction and time management. Additionally, foundation students experience deficiency in the cognitive group, mainly, the ability to apply the material learnt, do research and articulate comments and questions. No technological gaps were identified for all four course levels; however, in the affective category lack of netiquette and the challenge to stay motivated were uncovered for foundation-level students. No gaps in any of the categories were identified for Master and Bachelor-level students. In light of the exposed gaps, educators and school management teams need to reconstruct their practices to enhance learning equity.
Pengaruh Penerapan E-Samsat dan Sanksi Perpajakan terhadap Kepatuhan Wajib Pajak Kendaraan Bermotor (Studi Kasus pada Wajib Pajak di Samsat Makassar)
Authors: Nurchalifah S
Published: April 2024

The Effect of E-Samsat Implementation and Tax Sanctions on Motor Vehicle Taxpayer Compliance which variables have the dominant effect on motor vehicle tax compliance. The variables in this study are the implementation of E-Samsat as the first independent variable , tax sanctions as the second independent variable , and motor vehicle taxpayer compliance as the dependent variable . The population in this study are motor vehicle taxpayers registered in the Makassar Samsat in 2020 as many as 2236 people.
Analisis Penerapan PSAK 23 pada PT. Pegadaian (Persero) Cabang Pelita Makassar
Authors: Astiti Suci Putri , Putri Nurul Tanzilal Anugerah
Published: April 2024

Penelitian ini bertujuan untuk mengetahui pengakuan, pengukuran dan pengungkapan pendapatan berdasarkan PSAK No. 23 pada PT. Pegadaian (Persero) Cabang Pelita Makassar. Penelitian ini menggunakan metode deskriptif kualitatif. Penelitian ini melakukan wawancara dengan karyawan PT. Pegadaian (Persero) Cabang Pelita Makassar dapat memberikan informasi dan data-data yang diperlukan yang dapat dibutuhkan dalam hal ini sehingga dapat dianalisis dan dibandingkan dengan teori-teori yang ada. Hasil penelitian menunjukkan bahwa pengakuan laba pada PT. Pegadaian (Persero) Cabang Pelita Makassar diakui berdasarkan accrual basis yaitu pendapatan yang diakui pada saat perolehan barang atau jasa. Pengukuran pendapatan didasarkan pada nilai wajar tertentu. Pendapatan pengungkapan didasarkan pada kebijakan akuntansi. Jadi ini sudah sesuai dengan PSAK No 23.
Habermas: Tras un diagnóstico, un principio universal: la razón comunicativa
Authors: González Wilfredo
Published: April 2024

En la primera parte de este trabajo se hace un diagnóstico "a la manera de Habermas": la incertidumbre como clima de un mundo interconectado sin base común, la crisis de la “razón ilustrada” exitosa, incluida su expresión tecnocientífica y la razón crítica. En la segunda parte, se discute el resultado paradójico de la modernidad y sus promesas no cumplidas, así como la crisis de la razón moderna que, a pesar de la reacción postmoderna, aborda la búsqueda del fundamento de la ética del discurso y el problema de los presupuestos, las normas demostrablemente válidas, la importancia del lenguaje, la acción comunicativa y el parlamentarismo. La tercera sección presenta tres reflexiones finales, entre ellas la necesidad de continuar la lucha por la emancipación, la complejidad de responder a este diagnóstico en la práctica y las críticas que Habermas ha recibido por ignorar las diferencias culturales y reducir la comunicación a un intercambio lingüístico.
Un alegato en favor de la oralidad científica
Authors: Puerta Leisse Gustavo
Published: April 2024

En la primera clase que tuve en la carrera de Filosofía, el profesor nos recibió con una reflexión un tanto provocadora. Sostenía que si lo que realmente nos interesaba estudiar era la filosofía, entonces estábamos en el lugar equivocado. Argumentaba que aquello que nosotros estudiaríamos en las aulas serían, a lo sumo, rudimentos de historia de la filosofía; que con suerte aprenderíamos a leer y que, si por fortuna teníamos algún don para la escritura, deberíamos estar dispuestos a sacrificarlo en aras de aprobar la tesis indispensable para obtener el título de licenciado.
Steel Box Girder Bridges
Authors: Lally Andrew
Published: April 2024

The steel box girder bridge, because of its structural efficiency and aesthetics, has become increasingly popular as a bridge type. Because of four unfortunate erection accidents of box girder bridges in Austria, the United Kingdom, Australia, and Germany, this type of structure has received much recent attention. However, because of this attention, the behavior of steel box girder bridges is perhaps better understood than any other bridge type through extensive testing and improved mathematical models for use with computers. As a result of the United Kingdom investigations into the collapse of the Milford Haven and West Gate bridges, this will be the first long span bridge type with standard specifications covering its design and construction. The aerodynamically stable slender steel box girder bridge with cable stays will challenge the suspension bridge for the longest spans and may win. The steel box girder will be seen more commonly because of its aesthetics and economy in shorter spans as well, especially on horizontally curved alignment.
Quality Control in Design and Supervision Can Eliminate Lamellar Tearing
Authors: Thornton Charles H.
Published: April 2024

In the last few years, the design professions and the construction industry have experienced the occurrence of a pheomena called lamellar tearing in highly restrained joints within welded connections. Actually, the term "highly restrained" is relative; lamellar tearing can occur in connections which provide any degree of restraint to the connected members, but the restraint that is responsible for lamellar tearing is the localized restraint to contraction of individual welds. Lamellar tearing in steel is defined as a separation initiating in the parent or base material caused by thru-thickness strains induced by weld metal shrinkage. Due to the rolling process, plates and rolled members possess a lower ductility in the thru-thickness direction than parallel to the direction of rolling. This lower ductility, which is influenced by the presence of microscopic, non-metallic inclusions oriented in the direction of rolling, causes lamellar tearing when high thru-thickness strains are induced due to cooling and shrinkage of restrained welds. Recent design trends toward high strength steels, namely ASTM A572 and A588, and more sophisticated structural analyses which place higher demands on the material have increased the need toavoid occurrence of lamellar tearing. Furthermore, the increased use of welded connections for thick plate weldments and heavy jumbo member sizes also increases the frequency of occurrence of high joint restraint in connections.
Discussion: Steel Column Base Plate Design
Authors: Dixon Gerard , Mooseker William H.  , Gordon Paul , Sandhu Balbir S.
Published: April 2024

Discussion
Lateral Instability of Castellated Beams
Authors: Pattanayak Umesh C. , Chesson Jr.
Published: April 2024

The study reported herein deals with the lateral instability analysis of castellated beams using the principle of minimum potential energy. Several experiments available from the literature provide information for selecting the deformed configuration which satisfies the conditions of both statics and geometry at the boundary; certain idealizations are then made to characterize the geometrical features necessary for the purpose of analysis. The sets of Eqs. (12) and (14) provide the solution for lateral buckling of castellated beams under uniform load and concentrated load at mid-span, respectively. These equations include the solution for the external load when it is applied on the top flange, at the middepth longitudinal axis, or suspended from the bottom flange. It is observed that the critical load depends upon several parameters representing the geometrical features of castellated beams. In the case of commercially available products, the relations between critical loads and the governing parameters can be plotted with the help of the derived formulas for convenient use in practical design.
Simplified Solution to Interaction Equation
Authors: Phang Michael K.S. , Babyak R. Carey
Published: April 2024

According to the requirements of the AISC Specification, there are three equations, Formulas (1.6 1a), (1.6-1b), and (1.6-2), which must be considered in designing a steel column subjected to combined loading. In Formula (1.6-1a), the combined axial and bending stress is limited by stability, while yielding controls the combined stress in Formula (1.6- b). This factor is appropriately known as the amplification factor. The computed bending stress is required to be increased due to the additional bending stress induced by a secondary moment. This moment is caused by the compressive force and the deflection of the column due to moments applied at the ends and/or a transverse loading on the column. The purpose of this paper is to facilitate the calculations required for obtaining the modified bending amplification factor along with the allowable bending stresses of various steels available. It is hoped that with the use of the proposed charts, the time and effort of the designer will be greatly reduced.
Nomograph for Design of Channel Section Beams
Authors: Maitra N.
Published: April 2024

Channel sections are frequently used in the construction of operating platforms, passageways, stairs, etc. of industrial structures. They behave as beams and their moment of resistance for actual unbraced length must be calculated. The formulas used for channel sections are given in AISC Specification Sect. 1.5.1.4.6a. The value of d/Af (in these formulas) is available in manufacturers tables of properties for structural shapes as well as in the AISC Manual of Steel Construction. The value of Cb may be taken as unity for a simply supported system. For the convenience of designers, the AISC Manual of Steel Construction contains charts for determining the moment of resistance, MR, of wide flange beams when their unbraced lengths are known. However, no such charts are available for channel sections. A nomograph is presented herein for rapid determination of the values.
Seismic Drift Control Criteria
Authors: Teal Edward J.
Published: April 2024

Because building drift coefficients have been locked in with building dynamic response to many different earthquake ground motions and many opinions about probable, credible, and possible ground motions, this very important index of building seismic performance has been difficult to evaluate and standardize. It is suggested that the known part of the drift problem, the building flexibility and weight, be separated out into a Dynamic Flexibility Index. In order to compare buildings of different heights in relation to their dynamic response, which also varies with height, a Seismic Drift Index is suggested. A number of representative buildings have been analyzed for these indexes. These buildings show some indication of the practical index limits and set the stage for standardizing flexibility evaluation and criteria. Continued use of standardized evaluation indexes should provide a clearer picture of the practical limits involved and a ready means of evaluating performance on an equal comparative basis.
Discussion: Cable Connections in Stayed Girder Bridges
Authors: Kavanagh Thomas C.
Published: April 2024

Discussion
Design of Columns Subject to Biaxial Bending
Authors: Springfield John
Published: April 2024

Task Group 3 of the Column Research Council is charged with seeking improved methods for the design of columns subject to biaxial bending. As a result of recent research, this Task Group now can recommend improved design techniques for the most commonly used type of steel column, namely the wide flange shape. It is the purpose of this paper to review the existing AISC Specification design requirements for biaxially loaded beam-columns, to present the proposed new design procedures, and to compare the size of column section required by the existing and proposed design rules for several practical design problems.
A Simplified Method for the Flexural Design of Stiffened Hybrid Girders
Authors: Chong Ken P.
Published: April 2024

Hybrid girders are useful when strength is the governing factor in design. Due to the availability of higher strength steels and their structural efficiency, hybrid beams and girders are becoming more and more popular. The behavior of hybrid beams has been under extensive research and reported in various publications. However, there is still very little literature available on the design of hybrid beams. In 1970, Milek presented a comprehensive paper on hybrid girder design according to the 1969 AISC Specification. Recently, Schilling has published a paper which explores the optimal dimensions of both homogeneous and hybrid I-shaped beams due to bending moment only (web slenderness is assumed to be known). The theory and simplified method presented herein consider full unadjusted allowable bending stress in conjunction with reduced web contribution to the section modulus. The Adventage of this exact approach in flexural design of hybrid girders is that the dependency on b (ratio of web area to one flange area) is eliminated. Thus, no guesswork is required and no iterations are performed with respect to b. In other words a direct flexural design is possible by the simplified method. The method can also be applied for the analysis of a hybrid girder when the cross section is given
Design Example for Beams with Web Openings
Authors: Kussman Richard L. , Cooper Peter B.
Published: April 2024

Due to the increasing cost of energy and the difficulty of obtaining raw materials, economy has a high priority in all aspects of design. In the design of multistory steel buildings, savings can be realized by passing ductwork for heating, ventilation, and air conditioning systems through steel floor beams, rather than under them. Not only does this practice save in the overall height of the structure, along with all the related benefits in material savings, but it also saves in the cost of heating and air conditioning by enclosing less volume to be heated or cooled. Eccentric openings are of special interest because not all floor beams and girders are of the same depth at any given level. It is desirable to keep the ductwork on a relatively level plane to cut down on the cost of fabricating bends. It is doubtful that it costs any more to fabricate an eccentric opening in a steel beam than it does to fabricate a concentric opening. Thus, even more savings can be realized by using the eccentric opening. The addition of reinforcement is also sometimes desirable so that a heavier section is not required because of the opening. Design formulas have been developed for beams with concentric and eccentric web openings, both unreinforced and reinforced; the purpose of this paper is to illustrate the application of these formulas in a typical design problem.
Modern Approaches to Solution of the Wind Problems of Long Span Bridges (T.R. Higgins)
Authors: Scanlon Robert H.
Published: April 2024

During the process of design, the possible future loads and conditions to which a structure may be subjected must be conceived of and properly accounted for in analysis. It is hoped that, after the structure is erected, the loads and conditions which nature and man eventually impose on it will fall within the "envelope" of those previously conceived. When they do, the design is successful over its life span. Clearly the designer thus assumes responsibility for as wide a conception as possible of future loads. This conception is then translated into the structural form. Meanwhile, from another side, economics dictates that the structure not be overdesigned, which can occur if certain types of loads, though anticipated, are not well identified. In the case of large bridges, awareness of loading conditions has proceeded both from insight and by accident. Early efforts and failures to make proper assessments of static wind loads, going back a century and more ago, are well known. Even today, new information continues to be sought in this area. The vibratory responses of bridges to wind have also touched off many investigations which have led eventually to greater insights into bridge aerodynamic loading effects. Though history now identifies many related examples which preceded it, the Tacoma Narrows disaster of 1940 signaled the advent of the modern era of investigation into the aeroelastic problems of long span bridges. Until recently, however, this whole area of problems has remained less familiar to the designer than have the traditional static problems.
Discussion: Directional Moment Connections--A Proposed Design Method for Unbraced Steel Frames
Authors: Wiesner Kenneth B.
Published: April 2024

Discussion
Discussion: Seismic Design Practice for Steel Buildings
Authors: Teal Edward J. , SEAOC Seismology Committee
Published: April 2024

Discussion
Errata: Tension-Field Design of Tapered Webs
Authors: Falby W.E. , Lee G.C.
Published: April 2024

Errata
In-Plane Fatigue Strength of Plates with Laminar Discontinuities
Authors: Brockenbrough R.L. , Owens D.E.
Published: April 2024

Although laminar discontinuities in steel are of concern primarily in applications where through thickness tension loads are applied to the plate (or shape), information was desired on the effects of repeated loadings on plates loaded parallel with the discontinuity. An example of such an application would be the flange of a girder (or rolled beam) of a bridge, which has a subsurface discontinuity that extends across part of the flange width and runs parallel to the flange surface for some length before terminating in sound material or in a welded flange splice. It was questioned whether the end of the discontinuity would propagate under repeated loadings. Consequently, a series of fatigue tests were conducted on strap-type specimens with and without a midplane discontinuity. Two types of specimens, both with as-received mill surfaces, were tested: (1) an unwelded specimen and (2) a specimen with a transverse groove-welded joint. Specimens of both types, both with and without laminar discontinuities, were tested. All specimens were machined from the web of a rejected ASTM A572 Grade 50 steel beam. This paper presents the results of the fatigue tests. The work is part of Project 164, sponsored by the American Iron and Steel Institute through the Engineering Subcommittee of the Committee of Structural Steel and Steel Plate Producers.
LRFD Design Office Study
Authors: Wiesner Kenneth B.
Published: April 2024

The Proposed Load and Resistance Factor Design (LRFD) Criteria were subjected to practical testing in a two-part Design Office Study. Representative steel members were designed using the AISC Specification and using the LRFD Criteria for a range of building types, loads, and spans. The four primary objectives of the Design Office Study were accomplished. For example, some revisions and clarifications were made in the LRFD Criteria. The acceptability of member sizes designed by LRFD was verified. Where differences between AISC and LRFD designs resulted, they could be logically explained. In some cases LRFD Criteria were modified, in others the AISC Specification provisions were in process of revision. Using LRFD in the design office was not a difficult process, even without design aids, which are being developed. Applying LRFD does not require any complicated mathematics. After overcoming the initial hurdle of unfamiliarity, and with the help of design aids, designers will probably soon be using LRFD routinely in their offices.
Discussion: Simplified Design for Torsional Loading of Rolled Steel Members
Authors: Maitra Nirmal
Published: April 2024

Discussion
Graphical Aid for Design of Base Plate Subjected to Moment
Authors: Maitra Nirmal
Published: April 2024

The purpose of the base plate is to distribute the column load to the concrete pedestal in such a way that the stress does not exceed the allowable bearing stress of the concrete. When the load is concentric, the distribution of pressure is uniform and is equal to P over A. The solution offered by Blodgett2 requires solving cubic equations to obtain the value of x. A modular ratio of 10 has been used by him in a worked out example. An alternative shorter method, usually adopted by people on a construction site, is to assume that the centroid of the compression area is exactly at the center of the leeward anchor bolts.
Errata: Proposed Criteria for Load and Resistance Factor Design
Authors: Galambos Theodore V. , Ravindra M.K.
Published: April 2024

Errata
Discussion: Mill Building Design Procedure
Authors: Diefenderfer C.F.
Published: April 2024

Discussion
Analysis and Design of Framed Columns Under Minor Axis Bending
Authors: Kanchanalai T. , Lu Le-Wu
Published: April 2024

Columns in a building frame are often subjected to combined axial load and bending moment as a result of the frame action in resisting applied loads. A major concern in the design of framed columns is the effect of instability, which may reduce significantly the strength of the column or entire structure. There are two types of instability failure to which careful consideration must be given in design: member instability and overall frame instability. Figure 1a shows a typical load versus lateral deflection relationship of an unbraced frame. The gravity load P acting through the lateral deflection produces a secondary overturning moment, called P-D moment in the current literature. This additional moment reduces the strength and stiffness of the structure. Failure occurs when the lateral stiffness becomes so small that it is insufficient to resist any increase of the applied load. This is represented by the peak (instability limit) of the load deflection curve. The member instability effect results from the axial load acting through the deflection d occurring within the individual columns (Fig. 1b). It is obvious that if a frame is fully braced against sidesway only member instability effect need be considered in the design of its columns. Experience has shown that in a sway frame, frame instability is considerably more important than member instability, but the latter could lead to premature local failure. It has been reported that member instability may limit the load-carrying capacity of an unbraced frame even if the structure as a whole still has adequate stiffness to resist frame instability. This paper deals with the analysis and design of framed columns subjected to minor axis bending. Both sway and non-sway columns are included in the study. A review is presented of the current design procedures, which are based largely on the previous studies on columns bent about the major axis. For non-sway columns, the interaction formulas given in the AISC Specification have been found to give results which do not agree well with the theoretical solutions. For sway columns, specific design provisions need to be developed to account for the effect of frame instability.
Discussion: Analysis and Design of Framed Columns Under Minor Axis Bending
Authors: Nethercot David A.
Published: April 2024

Discussion
Computer-Aided Design of Stub-Girder System
Authors: Wang P.C. , Gotschall John A.
Published: April 2024

The stub-girder system for high-rise buildings is a relatively new and innovative concept in structural floor framing. The system, developed by Dr. Joseph Colaco in 1972, has gained considerable attention in recent years as a viable alternative to the traditional method of structural floor framing. The stub-girder system, in an effort to minimize overall space requirements while maintaining an independence between the various building systems, combines space for the mechanical ductwork in the design of the structural system. The result is an increase in the efficiency of both the structural frame and the mechanical layout, combined with a reduction in both space and material required. To date, several major buildings have been designed using the stub-girder system. Yet, the stub-girder system has been unable to gain wide-spread application in the construction industry due to the inability of average design firms to carry out the necessary computer analyses.
Some Aspects of Stub-Girder Design (T.R. Higgins Award)
Authors: Bjorhovde Reidar , Zimmerman T.J.
Published: April 2024

Much research effort has been devoted to studies of the strength and behavior of the many types of structural members and connections that are commonly used in steelframed buildings. The investigations have primarily focused on how to make the best use of the available materials, assuming that the end product would be safe, serviceable, and—as much as possible—economical structures. To that end significant advances have been made throughout the years, providing for an ever-improving quality of the work of the structural engineer. From his viewpoint, therefore, the attention of the researchers has been properly directed, because their studies have enabled him to perform his tasks better. It is readily recognized, however, that the structural aspects of most building projects form but part of the total construction package. The completed structure must provide adequate service to its users in all respects, covering structural performance as well as all of the electrical, mechanical and environmental requirements that must be satisfied. This is probably best achieved by a systems analysis of the project design, which requires extensive cooperation between all of the parties that are involved in the work. Thus, not only must the architect, the structural engineer and the general contractor work together as early as possible, but it is increasingly important that the other groups in the design team participate fully in all of the decision making processes. For a building this primarily refers to the mechanical and the electrical engineers, because many of the services that are planned by these professionals may influence the way the structure is designed and constructed.
Preliminary Analysis and Member Sizing of Tall Tubular Steel Buildings
Authors: Wong Chow H. , El Nimeiri Mahjoub M. , Tang John W.
Published: April 2024

More and more tall, slender multistory buildings have been designed and built in the last decade. For steel buildings in particular, the present architectural trend is toward the use of light panels with large glass areas. This trend requires the structural steel tube not only to resist all lateral loads to limit the drift to some acceptable values, but also to prevent racking of the glass panels. The analysis of tall steel tubes to account for all the lateral loads has been well established in the literature. Most available commercial computer programs, such as SAPIV, STRUDL II, NASTRAN, etc., are equipped to perform analysis of such systems both accurately and efficiently, but they are costly and time consuming. Therefore, the tendency is to limit their use for the so-called final analysis only. The proposed method of analysis is mainly applicable for rectangular shapes, but it could be extended to more general tubular shapes. Problems involving parameters like shear lag, warping, etc. are currently being studied by the authors
Stability of Metal Structures--A World View (Part 2)
Authors: SSRC ECCS
Published: April 2024

The advantages of the design interaction equation suggested by Chen et al.172 are that both strength and stability are covered by the same basic equation and the equation has universal applicability, for if the exponent for the particular section being designed has not been determined, it may conservatively be assumed to be unity.
Predesigned Bolted Framing Angle Connections
Authors: American Institute of Steel Construction
Published: April 2024

The current AISC Specification provisions governing the use of mechanical fasteners in structural applications are largely based upon rational rules provided in Guide to Design Criteria for Bolted and Riveted Joints by Fisher and Struik. This publication was sponsored by the Research Council on Structural Connections to evaluate and distill the results of voluminous research in this field that has been conducted since the late 1800s. Unfortunately, adoption of rules which provide the designer with an improved basis for understanding and estimating the real strength of structural connections has made connection design more complex. There are several modes of failure, any one of which may control the strength of a connection, and each must be considered. Thus, the design or checking of a given connection has become more demanding than in the past, when Specification provisions masked the true performance of connections behind overly conservative rules which addressed only a few possible modes of failure. For a complete framing angle connection design, the following must be considered: bolt shear, bearing on connected material, edge distance, block shear, net section shear, connection length, bolt spacing, slip resistance, hole size and shape and, in some cases, other special factors.
Calculator Program for Determining Properties of Built-up or Composite Members
Authors: Gossett Stephen R.
Published: April 2024

The advent of programmable calculators has increased the productivity of structural engineers considerably. Presented herein is a calculator program (written for the Hewlett- Packard HP-41C, utilizing its unique alpha-numeric capability) which eliminates the time-consuming calculations involved in determining the section properties of (a) built-up steel members or (b) composite sections. The program requires 314 program lines and 24 storage registers for execution. This article presents a brief description of the program, a printout of the program listing (Fig. 1), and a flowchart (Fig. 2). It also includes appropriate examples utilizing the HP 82143A printer.
Steel Members Subject to Axial Tension and Biaxial Bending Moments
Authors: Hsu C.T.T.
Published: April 2024

According to Sect. 1.6.2 of the current edition (1978) of the AISC Specification, steel members subject to both axial tension and bending stresses shall be proportioned at all points along their length to satisfy the requirements of Formula (1.6-1b). It is well known that Formula (1.6-1b) accounts for the cross-sectional strength of the members and that this form of the strength interaction equation is conservative for most sections and provides a factor of safety of at least 1.67 against the attainment of the ultimate moment capacity of the cross section.
Folded Steel Plate Roof for a Suburban Branch Bank
Authors: Shogren V.E.
Published: April 2024

The architectural design of the Union National Branch Bank building, Youngstown, Ohio, was keyed to the need for a structure with a striking appearance to serve as the focal point in a suburban shopping center. To achieve this appearance, architect P. Arthur DOrazio called for a circular building with a folded-plate roof and glass exterior walls. The author prepared preliminary structural studies for the project. These studies pointed to steel as the structural material that would fill the architectural requirements to the best advantage. This paper is not intended to be the last word on the design of a folded plate roof of this type. It is one engineers approach and treatment of this problem. There is never enough time to treat a new problem or situation as we would like. With more time, this structure could possibly have been refined and the cost reduced. There are, no doubt, other approaches that could have been made.
Lateral Support for Tier Building Frames
Authors: Galambos Theodore V.
Published: April 2024

The architectural design of the Union National Branch Bank building, Youngstown, Ohio, was keyed to the need for a structure with a striking appearance to serve as the focal point in a suburban shopping center. To achieve this appearance, architect P. Arthur DOrazio called for a circular building with a folded-plate roof and glass exterior walls. The author prepared preliminary structural studies for the project. These studies pointed to steel as the structural material that would fill the architectural requirements to the best advantage. This paper is not intended to be the last word on the design of a folded plate roof of this type. It is one engineers approach and treatment of this problem. There is never enough time to treat a new problem or situation as we would like. With more time, this structure could possibly have been refined and the cost reduced. There are, no doubt, other approaches that could have been made.
The Poplar Street Bridge
Authors: Shields E.J.
Published: April 2024

The Poplar Street Bridge will cross the Mississippi, between East St. Louis and the central business district of St. Louis. In addition to carrying Interstate Routes 55 and 70, it will be the terminal for Interstate 44 from the west and Interstate 64 from the east. This will be the first long span orthotropic steel plate deck girder bridge to be constructed in the United States. A contract for the substructure has already been awarded, and the superstructure will be advertised for bids in mid-1964. At the Missouri end of the bridge is the Jefferson National Expansion Memorial, a National Park commemorating the Louisiana Purchase, which will be completed, with its 630-ft stainless steel arch, in 1965. The view of the river from the Memorial will be framed on the north by the fine old Eads Bridge, a deck type arch truss design built in 1874, and on the south by the new bridge. Immediately west of the Memorial and adjacent to the central business district is an 80-acre area being redeveloped around a 50,000-seat sports stadium, which will be completed about the same time as the bridge.
Wind Connections with Simple Framing
Authors: Disque Robert O.
Published: April 2024

If a multi-story building is designed with simple framing (Type 2, AISC Specification Sect. 1.2), the frame must be braced to resist horizontal wind loads. This bracing may be provided by X-bracing, shear walls or "wind connections". Wind connections are normally designed to carry only the moments due to wind, without regard to the additional moments caused by gravity loading of the girders. This assumption that a connection is "intelligent" and "knows" which moments to carry and which not to carry may seem paradoxical. However, the validity of such a connection in providing wind bracing for a simple frame can be justified. The moment-rotation characteristic of a typical riveted or bolted moment connection is shown in Fig. 1. The shape of the curve depends on the stiffness of the connection and can only be determined by test. Tee-stub connections, for instance, usually have a steeper slope than does the typical "cap and seat angle" moment connection. The actual shape of the curve, however, does not effect the performance of the connection as a "wind connection" in conjunction with simple framing.
Research in Plastic Design of Multi-story Frames
Authors: Driscoll Jr. , Beedle Lynn S.
Published: April 2024

The eighth National Engineering Conference, held at Lehigh University in 1956, was devoted in its entirety to the subject of plastic design. At that time there were no plastically designed structures in the United States, or at least there were none that were a matter of record. Undoubtedly there must have been a number of structures designed on the basis of what has been described as a "plastic excuse for an elastic design"; and of course the provision included in the AISCSpecification in 1945 that permitted a 20 percent increase of stress at points of interior support could only be justified on the basis of the same concepts that led to the current plastic design techniques. The purpose of these remarks is to review briefly the advances made since 1956 and to describe in some detail the research being conducted at Lehigh University on the plastic design of multi-story building frames. The latter discussion is divided into two parts: braced frames and unbraced frames. In addition the results of recent pilot tests on a three-story structure are presented.
Old Bridges Give Clues to Steel Deck Performance
Authors: Wolchuk Roman
Published: April 2024

Whenever steel deck bridges are discussed, the question invariably arises: How well do the steel decks perform over the years? More specifically: How safe is a steel deck against corrosion? How good must the wearing surface be to protect it adequately? Is there a danger that the steel deck, with the top surface normally not accessible, will deteriorate under the surfacing? The answers to these questions are provided by actual experiences with steel deck bridges. The oldest of the new("orthotropic plate") type steel bridge decks in Europe are, by now, 15 years old. Some steel deck structures of older types are more than twice that age, and considerable experience with them has been accumulated. In this country, steel deck bridges of the new kind are still in the design or pre-construction stage. However, there are many "battledeck floor" type bridge structures in service, built in the 1930s. Two notable examples are the Harlem River Bridge and the Bronx-Kill Bridge in New York City built in 1936 and recently resurfaced. The writer had an opportunity, on behalf of American Iron and Steel Institute, to investigate the conditions of these steel decks after 27 years of service.
Analysis of Knee-Braced Portal Frames for Vertical Loading: Part 1
Authors: Vilas Howard K. , Surtees John O.
Published: April 2024

Knee-braced portal frames such as those shown in Figs. 1 and 2 are encountered from time to time in the design of buildings. The analysis of these bents for the vertical loading is easily done if a computer and necessary software are accessible to form and solve the stiffness matrix for the frame. If they are not accessible, then one is in a quandary, because the simultaneous deflections in the beam and the columns have to be accounted for in the solution. This paper looks into the longhand solution of such portal frames. Equations are developed and solutions given which are easy to apply. What is needed are the unit load and beam load deflections at the knee-brace locations. And, for given frame dimensions, these are calculated only once. As the member sizes are altered, one need only to change the matrix coefficients, which can be accomplished in little time. With two or three trials, economical selection of the members can be made.
Web Design Under Compressive Edge Loads
Authors: Elgaaly Mohamed
Published: April 2024

Webs of rolled and built-up beams and girders can be subjected to local in-plane compressive patch loads. Examples are, wheel loads, loads from purlins and roller loads during construction. For practical and/or economic reasons, transverse stiffeners are to be minimized or avoided except at critical sections. It is, therefore, necessary to check the unstiffened web under the edge compressive loading to insure no localized failure will occur. They type of loading under consideration is shown in Fig. 1. The length of the loaded patch "c" can vary between being so small as to be assumed concentrated to so large it can be extended over the entire length of the web panel. The later case will be referred to as distributed-edge loading. The localized stresses due to edge loading can be combined with global stresses of bending and/or shear. During the past 50 years, tests have been performed by several investigators to study the web behavior under compressive edge loads. These loads are mostly of the type shown in Fig. 1. However, the compression of the web over a support bearing block, as in Fig. 2, was also investigated. Extensive analytical and experimental studies of the elastic buckling and ultimate strength of webs loaded, shown in Fig. 1, were carried out during the last 20 years. The purpose of this report is to summarize the available analytical and experimental studies and develop recommendations for the design of unstiffened webs under compressive edge loads.
Steel Box Girder Bridges-Design Guides and Methods
Authors: Heins Conrad P.
Published: April 2024

During the past decade, there has been extensive use of steel box girders for straight and curved highway and transit structures. To meet the need for use of such structural elements, design criteria had to be established. Therefore, the purpose of this paper is to present information relative to the design criteria in addition to information on preliminary plate sizes, design aids, and computer-aided design of steel box girder bridges.
Simplified Approach to the Analysis and Design of Columns with Imperfections
Authors: Lui E.M. , Chen Wai-Fah
Published: April 2024

The design of columns makes an extensive use of the column curves. A column curve is a plot of the strength of the column (in stress or load form) vs. its slenderness ratio. The column curve for a perfectly straight column in the elastic or inelastic range can easily be derived using the eigenvalue approach. However, columns in actual building frames are rarely straight. The derivation of the column curve for an initially crooked column is very complex, with recourse to laborious numerical technique often necessary. The intent of this paper is to present a simple method to assess the strength of columns with initial out-of-straightness. A beam-column approach is used in the method. And the validity of the approach is determined by comparing it with existing column design formulas and with more elaborate computer models. A computer program is also written to help the designer use the proposed approach. In this paper, the fundamental theories of perfectly straight and initially crooked columns will first be reviewed. The derivation of the proposed column equation will then follow.
Economical Steel Plate Girder Bridges
Authors: Knight Richard P.
Published: April 2024

As a service to the bridge design profession, Bethlehem Steel has conducted hundreds of studies of steel plate girder bridges using its Preliminary Bridge Girder Optimization Program. The program is unique because it optimizes plate girder designs on the basis of least cost, not least weight. An evaluation of many study results leads to a number of guidelines which are offered in this paper. When applied by the bridge designer, these guidelines should result in economical steel plate girder designs for continuous composite bridges with span lengths of up to approximately 200 ft (61 m), representing a majority of the bridge population. Comparisons of various parameters are made on a cost index basis. These subjects are discussed: load factor vs. working stress design, weathering steel, painted high-strength steel, number of girders in a cross section, optimum web depth and thickness, transverse vs. longitudinal web stiffeners, flanges and flange splices, plus other considerations leading to cost effective steel plate girders for bridges. In the design of steel plate girder bridges, it used to be sufficient to determine a least weight solution and develop it as a complete set of plans for competitive bidding. That was believed to be the most economical design. However, over the past several years, many improvements have been made in design and analysis methods, materials and construction techniques, obliging the designer to consider an increased number of options. Todays heightened competition due to alternate bidding practices, including contractor sponsored alternates, makes it further incumbent upon all concerned with steel bridge design and construction to always strive for the most cost-effective solution.
A Composite Girder System for Joist Supported Slabs
Authors: Rongoe James
Published: April 2024

In current practice composite action between the concrete slab and the girder is not taken advantage of when framing a floor using standard open web joists and continuous metal decking. The reason is the girder is depressed (usually 2.5 in.) to receive the joist seat and therefore is not in direct contact with the concrete slab. Since the girder supporting the joists is noncomposite, the economic and other advantages of composite design are not realized. Also, because the girder is not framed flush with the joists, its bottom flange is usually a critical element in setting floor-to-floor heights and clearances for duct work. This paper describes a novel composite girder system to be used in conjunction with joist supported slab systems. As shown in Fig. 1, at the heart of the system are connections, such as tees, which are welded to the top flange of the girder intermittently between the joist locations. (These pieces are analogous to stubs in a stub-girder system). The tops of these connections are flush with the bottom of the slab and thus provide a surface to which standard shear connectors can be attached. The former gap between the bottom of deck and top of girder can now be utilized structurally.