# 【精品文檔】16中英文雙語土木工程建筑道路橋梁工程技術設計外文文獻翻譯成品：腹板開洞簡支混合梁設計.doc

此文檔是畢業設計外文翻譯成品（ 含英文原文+中文翻譯），無需調整復雜的格式！下載之后直接可用，方便快捷！本文價格不貴,也就幾十塊錢！一輩子也就一次的事！ 外文標題：Design of Simply-Supported Composite Beams with Large Web Penetrations 外文作者：Dr. Mark Patrick, Dr. Cameron Chick, Dr. Daya Dayawansa, Dr. Chong Chee Goh, Mr. Rodney Wilkie 文獻出處：Onesteel Market Mills Composite Structures Design Manual,2018(如覺得年份太老，可改為近2年，畢竟很多畢業生都這樣做) 英文4489單詞，24896字符(字符就是印刷符)，中文6697漢字。 Design of Simply-Supported Composite Beams with Large Web Penetrations Preface This design booklet forms part of a suite of booklets covering the design of simply-supported and continuous composite beams, composite slabs, composite columns, steel and composite connections and related topics. The booklets are part of the OneSteel Market Mills’ Composite Structures Design Manual which has been produced to foster composite steel-frame building construction in Australia to ensure cost-competitive building solutions for specifiers, builders and developers. The additional design information necessary to allow large web penetrations to be incorporated into simply-supported bare steel and composite beams is presented in this booklet. Design issues with respect to strength and deflection control are addressed. The non-composite bare steel state arises during construction prior to the concrete hardening. Large rectangular and circular penetrations are often made in the steel web of composite beams for the passage of horizontal building services. This allows the plenum height to be reduced when using economical, standard UB and WB steel sections. However, large penetrations weaken a composite beam locally and reduce its overall flexural stiffness, and therefore their effect must be considered in design. Neither the Steel Structures Standard AS 4100 nor the Composite Beam Standard AS 2327.1 contains design provisions for large web penetrations. The rules provided in the booklet for designing bare steel beams with large penetrations are compatible with AS 4100. For the composite state, the rules are compatible with AS 2327.1, and have been proposed as an acceptable method of design to be referred to in Amendment No. 1 of this Standard expected to be published this year. Information is also given to assist design engineers to understand the engineering principles on which the design methods are based. This includes: (a)explanatory information on important concepts and models; (b)the limits of application of the methods; and (c)worked examples. Design capacity tables are given in Appendix C to simplify the strength design process. The information provided can be used to design for either the bare steel or composite states. The tables cover a range of situations involving 300PLUS? UB and WB steel sections supporting a composite slab and incorporating large web penetrations. A spreadsheet program named WEBPENTM is available to assist with the strength design calculations. Although these design aids are intended to make the design process more efficient, it is essential that the user obtain a clear understanding of the basis of the design rules and the design approach by working through this document and the relevant parts of associated design Standards such as AS 4100 and AS 2327.1 SCOPE AND GENERAL Scope The additional design information necessary to allow large web penetrations to be incorporated into simply-supported bare steel and composite beams is presented in this booklet. Design issues with respect to strength and deflection control are addressed. The steel beam must be a doubly- symmetric I-section. The overall beam design for the bare steel and composite states is assumed to have been carried out in accordance with AS 4100 [1] and AS 2327.1 [2], respectively. The penetrations may be (see Fig. 1.1): ·rectangular or circular in shape (within the specified limitations); ·unreinforced, or reinforced (in accordance with the specified details) ; and ·concentric or eccentric to the centroid of the steel section. The application of the strength design method is defined by the conditions given in Section 6.2. This document should be read in conjunction with the design booklet Design of Simply-Supported Composite Beams for Strength, DB1.1 [3] and AS 2327.1, noting that some relevant material from these documents has not been duplicated herein. In accordance with Clause 5.2.3.1 of AS 2327.1, the effect of holing of the steel beam due to a web penetration may be ignored provided the greatest internal dimension of the penetration is not greater than 0.1 times the clear depth of the web. It follows that penetrations larger than this should be considered as large, and their effect determined in accordance with the information provided in this document. General The strength design method presented herein is based on a method recommended by an ASCE Task Committee [4]. The method has been verified with some experimentally-based investigations conducted in Australia, and modified to suit Australian design practice and conform to relevant Australian Standards. Further details about the development of the strength design method can be found elsewhere [5,6]. The deflection design method has been developed from work originally presented by Tse and Dayawansa [7]. Further information about this method can be found in [5]. Large rectangular and circular penetrations are often made in the steel web of composite beams for the passage of horizontal building services. This allows the plenum height to be reduced when using economical, standard UB and WB steel sections. However, large web penetrations weaken a composite beam locally and reduce its overall flexural stiffness. Neither the Steel Structures Standard AS 4100 nor the Composite Beam Standard AS 2327.1 contains design provisions for large web penetrations. The strength design method was adopted after a detailed review of four proposed methods, viz. ASCE Task Committee [4], Redwood and Cho [8], Lawson [9] and Oehlers and Bradford [10]. The method adopted for Australian design practice, proposed by ASCE Task Committee [4], has been modified to conform to the relevant Australian Standards. The suitability of the modified method has been verified on the basis of an Australian experimental program. A reliability analysis has been conducted using the results of the experimental program and other experimental data available from overseas literature, to determine an appropriate value for the strength factor, f [11]. In this regard, consideration has also been given to the improved performance of a composite beam that can be derived by placing DECKMESH? [12] in the region of a penetration [13]. Accordingly, it is recommended herein that this reinforcing product is used in the region of each web penetration when the profiled steel sheeting is deemed perpendicular to the steel beam. (Note: this product is not suitable to be used in situations when the sheeting is parallel to the steel beam – refer to design booklet DB1.2 for further guidance.) The cost implications of choosing between reinforced or unreinforced web penetrations is an important consideration during the design stage, noting that the intention of using penetrations is not only to obtain an acceptable floor-to-floor height, but also a more cost-effective structure. For this purpose, it is recommended that a rational method of costing steelwork is used which takes into account the specific labour and material costs involved in fabricating the penetrations including any steel plate reinforcement [14] 2TERMINOLOGY Some important terminology used in this booklet is summarised in this section. Reference should also be made to Section 2 of DB1.1 and Clause 1.4.3 of AS 2327.1 for additional terminology. Bottom T-Section The portion of the steel beam cross-section lying below the penetration. High Moment End (HME) The end of a penetration subjected to the higher primary bending moment. Low Moment End (LME) The end of a penetration subjected to the lower primary bending moment. Primary Bending Moment The bending moment at a beam cross-section due to overall bending action ignoring secondary effects (see Fig. 3.2). Rigid Arm A part of a beam assumed to be rigid in the model used for deflection calculations. Secondary Bending Moment The additional bending moment induced in the top and bottom T-sections as a result of Vierendeel action over the length of the penetration (see Fig. 3.2). Steel T-Section The bottom T-section or the top T-section, excluding the concrete flange in the case of a composite beam. Top T-Section The portion of the steel beam cross-section lying above the penetration, inclusive of the concrete flange in the case of a composite beam. Vierendeel Action The development of secondary bending moments in the top and bottom T-sections due to the presence of vertical shear force across the penetration. Web Penetration Reinforcement Steel plates or flat bars continuously welded to one or both sides of the web of the steel beam, as close as practicable to the top and bottom horizontal edges of the penetration. 3 DESIGN CONCEPTS Strength Design Behaviour in the Region of a Web Penetration A large rectangular or circular penetration made in the steel web of a simply-supported steel or composite beam weakens the beam locally by reducing both the moment and shear capacities. This reduction in strength can be partly overcome by welding steel plates or flat bars to the web along the horizontal edges of the penetration as reinforcement. However, the economics of using web penetration reinforcement needs careful consideration. In the absence of vertical shear force, the moment capacity of a beam cross-section at a large web penetration is reduced as a direct result of the loss of steel web area. Vertical shear force at the penetration gives rise to a more complex state of equilibrium as a result of Vierendeel action occurring over the length of the penetration. This action causes additional secondary moments to develop in the top and bottom T-sections. Its effect becomes more pronounced as the penetration length increases and as the shear-to-moment ratio increases, which explains why both of these factors need to be controlled during design. The main features that become visible in the region of a web penetration at ultimate load are shown in Fig. 3.1. The most-highly stressed areas are located at the high- and low-moment ends of the penetration, denoted HME and LME, respectively. These features are briefly explained as follows. The secondary moments may be sufficiently large to cause the slab to crack perpendicular to the steel beam, both in the top face at the LME and the bottom face at the HME. The combined effects of flexure, shear and Vierendeel action can lead to yielding in the top and bottom T-sections, and plastic hinges can form at their ends. In many cases, large differential vertical deflection between the two ends of the penetration occurs when a major diagonal crack forms in the concrete slab directly above the penetration. This crack can lead to a sudden drop in the load-carrying capacity of the composite beam, significantly reducing its ductility [13]. Large tensile forces develop in the shear connectors at the HME region of the penetration [15], particularly prior to the onset of the diagonal crack. The likelihood of diagonal cracking in the slab can be influenced by a number of factors, such as: the moment-shear ratio; the geometry of the profiled steel sheeting; the orientation of sheeting ribs; and the slab reinforcement When the sheeting ribs are orientated perpendicular to the longitudinal axis of the steel beam, the diagonal crack initiates at the top of the ribs and rapidly propagates through the cover slab causing failure. Tests show that the behaviour of a composite beam with the sheeting laid perpendicular to the steel beam can be significantly improved if the width of this crack is controlled using special steel reinforcement in the concrete slab [13]. This steel reinforcement was originally developed to prevent rib shearing failure in composite edge beams [16,17,19], and is now commercially available as DECKMESH [12]. Primary and Secondary Bending Moments The existence of primary and secondary bending moments in the region of a large web penetration is illustrated in Figure 3.2. Effect of Web Penetrations on Maximum Compressive Force in Concrete Flange In a simply-supported composite beam, the maximum compressive force that can develop in the concrete flange at any particular cross-section can be governed by various factors such as the strength and distribution of the shear connectors, the tensile capacity of the steel section, the compressive strength of the concrete, etc. When a web penetration is incorporated in the steel beam, this can reduce the compressive force that can develop in the concrete flange at some of the other cross-sections of the composite beam, as shown in Fig. 3.3 (where it is assumed that the shear connector distribution remains unchanged after the introduction of the web penetration, and that they are uniformly spaced). Design rules to cater for this situation are given in Clause 6.6 of AS 2327.1. Figure 3.3 Influence of Web Penetration on Maximum Compressive Force in Concrete Flange Design Vertical Shear Capacity In the case of composite beams without large web penetrations designed in accordance with AS 2327.1, it is assumed that the shear force is resisted by the steel beam alone when calculating the design vertical shear capacity. This simplifying assumption is considered too conservative at cross-sections within a web penetration when a significant portion of the steel web has been removed. It is assumed that the concrete slab also contributes to the design shear capacity of the composite beam, if the combined design shear capacity of the top and bottom steel T-sections is insufficient to resist the design vertical shear force. The model used to determine the nominal vertical shear capacity of a composite beam in the region of a web penetration is presented in Section 4.2. Moment-Shear Interaction In accordance with the strength design method given in AS 2327.1, the nominal moment capacity of a cross-section of a composite beam without a web penetration is assumed to be affected by shear when the shear ratio, , is greater than 0.5 (see Clause 6.4 of AS 2327.1). In this case, the nominal moment capacity is assumed to reduce linearly with the shear ratio until the entire steel web is fully utilised resisting shear, and hence makes no contribution to moment capacity. When 1.0 , the only contribution to the moment capacity from the steel section is due to the steel flanges. The resulting tri-linear moment-shear interaction curve is shown in Fig. D3.2 of AS 2327.1. It should be noted that a different moment-shear interaction relatio