scholarly journals A new type of hollow-shallow steel and concrete composite floor beam

Author(s):  
Vu Anh Tuan ◽  
Han Ngoc Duc ◽  
Nguyen Dinh Hoa ◽  
Nguyen Tran Hieu ◽  
Nguyen Trung Kien

Recently in Vietnam, steel-concrete composite structures especially composite beams are widely constructed in high-rise buildings. To apply broader in construction field mainly in secondary beam systems, the new type of slim-floor composite beam is proposed to aim at reducing the cost, saving the raw material, and decreasing the overall floor depth for sustainable development orientation. This type of floor beam structure consists of built-up hollow-shallow steel beam mandatory connected with cast in situ concrete slab through the openings at both side of web along the beam. The shear connection level of composite beam is depended on not only the friction at the connected surface between hollow steel section and concrete but also the shear resistance of concrete dowels, which go through the openings. The paper deals with an innovative shape of cross-section and design philosophy of composite beam according to EN 1994-1-1.

Author(s):  
W. Lorenc

<p>The introduction of composite dowels in Europe at the beginning of the last decade led to the creation of new forms of composite bridges in which a T-profile is used instead of an I-beam. Both the construction and design methods are new. The paper presents the bridges using this new type of shear connection. The variety of forms and dynamic development of a new type of construction is presented. The development history and the latest shear connection design guidelines are summarized. Reference was made to the basic design principle for composite beams with the associated concrete slab: the omission of part of the transverse force transmitted by the concrete slab. To understand design basis for new forms is to deeply understand that they are beyond current version of Eurocode 4: "3 + 2 ≠ 4 and Eurocode 3 + Eurocode 2 ≠ Eurocode 4". The above in a good way reflects the sense of what new forms are and why their design is complicated.</p>


2014 ◽  
Vol 13 (2) ◽  
pp. 265-274
Author(s):  
Marek Łagoda ◽  
Krzysztof Śledziewski

The theme of the paper is the effect of scratching of reinforced concrete slab on the work of a steel-concrete composite beam. The paper evaluates the state of knowledge in the field of composite structures, in particular, statically indeterminate structures with concrete in tension zones. Additionally, in a nutshell, it describes the current practice of design. Moreover, experimental studies were described on continuous beams that were made by the authors. A proposal for further work on this topic was also presented.


Author(s):  
А.Ю. Боташев ◽  
А.А. Мусаев ◽  
М.А. Саидов

Устройство с тепловым энергоприводом для прессования является разновидностью импульсных устройств. Оно позволяет значительно снизить себестоимость прессуемых железобетонных изделий. Для обеспечения высокой мощности устройства для прессования и уменьшения его габаритных размеров и металлоемкости в его конструкции используется тепловой энергопривод внутреннего сгорания. Существующие прессы для прессования бетонных изделий большой мощности конструктивно сложны и дороги. Поэтому прессование применяют в основном при формовании штучных бетонных изделий небольшого размера. Разработан новый вид устройства для прессования крупногабаритных бетонных изделий. Для выполнения этой цели сделано устройство с тепловым энергоприводом для прессования крупногабаритных бетонных изделий, обеспечивающее высокую прочность этих изделий. Разработанное устройство имеет высокую производительность. Получены зависимости для определения энергосиловых параметров данного устройства, а также необходимой величины давления топливной смеси, обеспечивающей осуществление процесса прессования. В частности, для прессования бетонной плиты площадью 1мвполне достаточно давления топливной смеси 0,9 МПа. При этом давление и усилие прессования составляют: P = 11,7 МПа При увеличении давления топливной смеси до 2 МПа усилие прессования достигает 20 МН, что вполне достаточно для прессования крупногабаритных бетонных изделий A device with a thermal power drive for pressing is a type of impulse devices. It allows one to significantly reduce the cost of compacted reinforced concrete products. To ensure high power of the device for pressing and to reduce its overall dimensions and metal consumption, a thermal energy drive of internal combustion is used in its design. Existing presses for molding concrete products of high power are structurally complex and expensive. Therefore, pressing is used mainly in the formation of small-sized concrete pieces. This article is devoted to the development of a new type of device for pressing large-sized concrete products. To achieve this goal, we developed a device with a thermal power drive for pressing large-sized concrete products, which ensures the high strength of these products. The developed device has a high performance. We obtained dependences for determining the power parameters of the device, as well as the required pressure of the fuel mixture, which ensures the implementation of the pressing process. In particular, for pressing a concrete slab with an area of 1 m, a fuel mixture pressure of 0.9 MPa is sufficient. In this case, the pressure and the pressing force are: P = 11,7 МРа , With an increase in the pressure of the fuel mixture to 2 MPa, the pressing force reaches 20 MN, which is quite enough for pressing large-sized concrete products


Author(s):  
Matthew Sjaarda ◽  
Scott Walbridge ◽  
Jeffrey S. West

Steel-concrete composite construction is used extensively in bridges across North America. The welded shear stud is the standard connector used today, but other connectors, such as the through-bolt connector, may have advantages for precast construction or applications where better fatigue resistance or deconstructability is desired. The standard method of assessing the performance of a shear connector is through the use of push tests. However, the load-slip curves that result from these tests do not accurately predict load-slip behavior at the shear interface of the beams and girders they are meant to simulate. In this paper, a model is presented that predicts composite beam behavior using elastic material properties and nonlinear shear connector load-slip curves. The finite element (FE) model features link connector elements between a steel beam and concrete slab that can be programmed to simulate different connector types. Although the model can be used with push test load-slip curves as inputs, it is shown that a much better prediction can be made using force-deformation data from experimental beam tests or FE analysis. Results are discussed for stud connectors and through-bolt connectors, and it is shown that while through-bolts allow more interfacial slip and overall deflection, material stresses and composite interaction are not affected as much as might be expected. The outcome of this work is a comparison tool which can be used to assess the viability of current and future shear connection alternatives with the goal of achieving an economical and structurally sound shear connector.


2018 ◽  
Vol 7 (3.10) ◽  
pp. 54
Author(s):  
T Subramani ◽  
A Periasamy

Composite plays a vital role in replacing the existing mild steel in reinforcement and exterior truss structure. This study proposed to design shear connector for joining concrete slab and steel section. Shear connectors has analyzed and predict the best connector for a particular composite beam with respect to static load and the amount of steel in the connector as a common aspect. The use of composite structures is increasingly present in civil construction works nowadays. Composite beams, especially, are structures which include substances, a metal phase placed in particular inside the tension region and a concrete phase, positioned in the compression go sectional location, both are related with the aid of steel gadgets called shear connectors. The main features of this connector are to permit the weight for the joint the beam-column, to restriction longitudinal slipping and uplifting on the factors interface the shear forces. Our project paper presents 3D numerical models of steel-concrete composite beams to simulate their structural behaviour, with emphasis on the beam column interface using Simulations software ANSYS 18.1 based on the Finite Element Method. Mostly these type of structures are widely used in the dynamic loading structures like bridges and high rise buildings.  


2017 ◽  
Vol 26 (3) ◽  
pp. 69-78 ◽  
Author(s):  
Paweł Helbrych ◽  
Maciej Major ◽  
Jacek Nawrot

Abstract The paper proposed a numerical model of a shear connection between a reinforced concrete slab and a steel shape. The connection was made using a top-hat profile. A method for conducting experimental research on shear connections in the composite structures was presented. Geometric dimensions and material parameters of the analysed model of connection, on which the experimental research was conducted, were noted. The results of the conducted experimental research were compared to the results of the numerical analysis performed using ANSYS software. displecement curves were analysed for both cases and any correlation between experimental and numerical results was noted.


1983 ◽  
Vol 10 (4) ◽  
pp. 713-721 ◽  
Author(s):  
R. G. Redwood ◽  
G. Poumbouras

Tests of composite beams comprising a concrete slab supported on a steel deck and a steel wide-flange shape containing large web openings are described. Special attention is directed to the amount of shear connection between slab and steel section in the region of a web hole, and on the effect of construction loads acting on the steel section prior to composite action being effective.It is shown that limited shear connection at the hole will significantly affect the strength when loading produces a high shear-to-moment ratio, and a theory is presented which conservatively takes this into account. The effect of construction loads on unshored construction is shown to be small when these do not exceed 60% of the non-composite beam resistance at the hole.


2018 ◽  
Vol 272 ◽  
pp. 141-146
Author(s):  
Pavel Jursík ◽  
Jan L. Vítek ◽  
David Čítek

Nowadays the extraordinary mechanical properties of UHPC can be used for real structures. The exceptionally high bond of reinforcement and UHPC together with significant shortening of lap length are the key features for the simplification of joining of precast elements. The properties of UHPC can be very well used also for providing of subsequent shear connection of composite structures. This paper is focused on analysis of performance of a combined joint where connection of precast elements as well as subsequent composite action between steel and concrete parts of steel-concrete composite structure are carried out in one compact detail. Instead of the traditional headed shear studs there were used local perforated puzzle sheets. More resilient connection of shear sheets to the top flange and a high resistance of UHPC allow for reduction of the extent of shear connectors. In experimental measurements carried out on six beams the behavior of shear connection of conventional monolithic concrete slab with continuous perforated shear sheet and shear connection of precast slab with the joint made of UHPC with local puzzle sheets were compared. During the experiment it has been proven that the performance of the beams with both variants of shear connection is very similar even with the significant reduction of the extent of shear connectors. Numerical analysis which describes the stressing in this detail confirms such behavior.


2016 ◽  
Vol 703 ◽  
pp. 371-375
Author(s):  
Jun Xia ◽  
Zhi Qiang Shen ◽  
Kun Liu

The flexural behavior of tapered cross-section steel-concrete composite material beams frequently used in structural engineering is strongly influenced by the type of shear connection between the steel beam and the concrete slab. The 1D high order finite element model for tapered cross-section steel-concrete composite material beams with interlayer slip were established in this paper. The Numerical results for deflection and interlayer slip of the composite beam with two typical boundary conditions were compared with ANSYS using 2D plane stress element. The 1D element is more efficient and economical for the common tapered cross-section steel-concrete composite material beams in engineering.


TAPPI Journal ◽  
2014 ◽  
Vol 13 (11) ◽  
pp. 37-43 ◽  
Author(s):  
LIISA KOTANEN ◽  
MIKA KÖRKKÖ ◽  
ARI ÄMMÄLÄ ◽  
JOUKO NIINIMÄKI

The use of recovered paper as a raw material for paper production is by far the most economical and ecological strategy for the disposal of waste paper. However, paper production from recovered paper furnish generates a great amount of residues, and the higher the demand requirements for the end product, the higher the amount of rejected material. The reason for this is that the selectivity of the deinking process is limited; therefore, some valuable components are also lost in reject streams. The rejection of usable components affects the economics of recycled paper production. As the cost of waste disposal continues to increase, this issue is becoming more and more severe. This paper summarizes the current state of the resource efficiency in recycled pulp production and provides information on the volumes of rejected streams and the usable material within them. Various means to use these reject streams are also discussed, including the main findings of a recent thesis by the main author. This review summarizes current internal and external use of reject streams generated in the deinking operations.


Sign in / Sign up

Export Citation Format

Share Document