Kesme Bağlantısı nedir?
A shear connection is a joint that transfers shear force between two members without transferring meaningful moment. If a beam carries internal kesme kuvveti, that force passes through the connection into the supporting column as eksensel kuvvet. Shear connections behave as a pin (FFFFFR in SkyCiv Structural 3D), unlike moment bağlantıları, which hold the end rotation.
In AISC 360-16 terms this is a altında da mevcuttur bağlantı (B3.4): it is assumed to rotate freely and to carry negligible moment. GİBİ 4100:2020 calls the equivalent arrangement simple construction. A semi-rigid joint is a third case, with real but partial rotational stiffness, and it has to be modelled that way rather than treated as simple.
A plate or angle carries the force between the two members. Yukarıdaki örnekte, any downward load on the beam passes into the supporting member through the angle. Because nothing restrains the beam flanges, the joint can rotate, which is what makes it a shear connection rather than a moment connection.
SkyCiv Professional paketi ayrıca çelik içerir are the most common connection in steel framing. Where a frame is braced, the bracing provides the lateral stability, so moment connections are needed only where the frame relies on frame action. That is why most designers reach for a shear connection wherever the analysis allows: they are simpler to fabricate and cheaper to erect.
Shear connection design comes down to following the beam reaction from the beam web, cıvatalar aracılığıyla, plate or angle and welds, into the support, and checking every part it passes through. This page sets out that procedure with the AISC 360-16 denklemler, and links to five fully worked AISC calc sheet examples that apply it to real connections.
SkyCiv Connection Design checks shear connections to AISC 360-16 hem ASD'de hem de LRFD'de, ve GİBİ 4100:2020.
Kesme Bağlantı Çeşitleri
Shear connections are named after the component that carries the load and where it sits. Which ones are available depends on the design code and on what the beam frames into, so the lists below are split that way.
I kesitli sütuna kiriş, or beam to beam (AISC 360-16)
Six configurations, each available framing to the column flange, to the column web, or beam-to-beam through the web:
- Tek Açılı. One L-shaped bracket between the beam web and the support. The lightest option, and the most flexible, so it suits light loads. The reaction sits off the support-side bolt line, so those bolts carry an eccentricity (çalışılan örnek).
- Çift Açılı. Angles on both faces of the beam web. The extra angle puts the beam-side bolts in double shear and makes the connection more forgiving during erection, which is why it is the workhorse for heavier beams (çalışılan örnek).
- Tek Plaka. The shear tab. One plate, shop-welded to the support and bolted to the beam web. Usually the cheapest of the group, because there is one weld line and one bolt group (çalışılan örnek). When the plate has to reach past the column flanges into a column web, it becomes an extended single plate, which is designed differently (çalışılan örnek).
- Çift Tabak. Plates on both faces of the web, used where a single plate cannot carry the shear or fit the required bolt group.
- Uç plakası. A plate welded to the beam end and bolted to the support. It needs the beam cut to length accurately, since the plate leaves no adjustment (çalışılan örnek).
- Doğrudan Kaynaklı Ağ. The beam web welded straight to the support, with no intermediate plate or angle. There are no bolts to check, but it needs field welding and gives up the erection tolerance a bolted detail provides.
HSS sütununa kiriş (AISC 360-16)
Framing into a hollow section changes what fits, because there is no flange to bolt to and no access to the far side for a wrench. Five configurations are available:
- Tek Açılı ve Çift Açılı
- Tek Plaka
- Tek WT. A tee cut from a wide flange, its stem welded or bolted to the beam web and its flange to the column face.
- Koltuk Açısı. An angle under the bottom flange carrying the beam in bearing, normally with a top clip for stability. Unlike the web-connected types, this one works off the flange.
GİBİ 4100:2020
The Australian code covers beam-to-I-column and beam-to-beam framing, with four configurations:
- Web Tarafı Plakası, the AS 4100 name for the shear tab.
- Esnek Uç Plakası
- Tek Açılı ve Çift Açılı
GİBİ 4100 coverage is shear only, and does not extend to HSS columns, kanallar, bracing or splices. Those are AISC 360-16.
How to design a shear connection to AISC 360-16
Every shear connection is designed the same way: take the factored beam end reaction, [mathin] R_{u} [mathin] (veya [mathin] R_{a} [mathin] for ASD), and check each part of the load path against it. The reaction leaves the beam web, passes through the beam-side bolts or welds into the plate or angles, and then through the support-side bolts or welds into the column or girder. A failure anywhere along that path is a failure of the connection.
Aşağıdaki denklemler AISC'nin LRFD formlarıdır 360-16 ve AISC Kılavuzu 15. Baskı. ASD için, yer değiştirmek [mathin] \phi R_{n} [mathin] ile [mathin] R_{n} / \Omega [mathin], SkyCiv Oluşturucu API'sı [mathin] \Omega [mathin] aynı maddede verilmiştir ([mathin] \Omega = 2.00 [mathin] nerede [mathin] \phi = 0.75 [mathin], ve [mathin] \Omega = 1.50 [mathin] nerede [mathin] \phi = 1.00 [mathin]).
1. Detaylandırma sınırları (J3.3, J3.4)
Herhangi bir güç kontrolünden önce, the geometry has to be buildable and match the assumptions behind the strength equations. Cıvataların minimum aralığa ve kenar mesafesine ihtiyacı vardır, İngiliz anahtarının dönecek alana ihtiyacı var, and the plate or angle should be at least half the beam’s T dimension deep so the beam end stays stable. Minimum cıvata aralığı:
[math] s_{min} = 2\tfrac{2}{3}\, d_{b} \qquad (3\, d_{b}\ \text{preferred}) [math]
Minimum edge distances come from Table J3.4, with an increment from Table J3.5 when the edge is measured across a slotted hole. In the worked examples a detailing limit is often the highest ratio in the whole connection. That is normal: designers lay the bolts out at the limits to keep the plate small.
2. Bolt shear and eccentricity (J3.6, Manuel Parça 7)
The strength of one bolt in shear is:
[math] \phi r_{v} = \phi\, F_{nv}\, A_{b}\, N_{s} = \phi\, F_{nv}\, \frac{\pi}{4} d_{b}^{2}\, N_{s}, \qquad \phi = 0.75 [math]
nerede [mathin] F_{nv} [mathin] comes from Table J3.2 (54 ksi for A325-N and 68 ksi for A490-N, grades within ASTM F3125) ve [mathin] N_{s} [mathin] is the number of shear planes. The bolts in a double angle beam-side group are in double shear, [mathin] N_{s} = 2 [mathin].
The reaction rarely acts on the bolt line. When it sits a distance e away, the bolts carry a moment [mathin] R_{u}\, e [mathin] as well as the shear, and the group delivers fewer than n bolts’ gücün değeri. Anlık dönme merkezi (ICOR) method finds that reduced count, the coefficient C, from the load-deformation curve of each bolt (Manuel Denklem. 7-1):
[math] R = R_{ult} \left( 1 – e^{-10\Delta} \right)^{0.55} [math]
[math] \phi R_{n} = C\, \phi r_{v} [math]
How much eccentricity to design for depends on the connection type, and this is where the five worked examples differ most:
| Bağ | Tasarımın tuhaflığı | Effect in the worked example |
|---|---|---|
| Tek plaka (conventional) | [mathin] e = a/2 [mathin] from Manual Table 10-9 | 2 in to the bolt line becomes e = 1 içinde; three bolts give C = 2.71 |
| Extended single plate | Full distance from the weld to the bolt group | e = 10.25 in cuts 14 cıvatalar 6.29 effective bolts |
| Tek açılı, destek tarafı | [mathin] e = g + t_{w}/2 [mathin], from the support bolt line to the middle of the beam web | e = 1.85 in cuts 2 cıvatalar 1.24 cıvatalar’ worth |
| Çift açı, ışın tarafı | Neglected (Manuel Parça 10) | The bolt group is treated as concentric |
For the iteration itself, görmek ICOR kullanarak cıvata grubu hesaplaması, or run a bolt group in the cıvata hesaplayıcı.
3. Cıvata yatağı ve yırtılma (J3.10)
Each bolt pushes on the edge of its hole. The ply either crushes locally around the hole (rulman) or tears a strip out to the next hole or the edge (yırtma). With deformation at service load a design consideration:
[math] \phi r_{n} = \phi\, \min\left( 1.2\, l_{c}\, t\, F_{u},\ 2.4\, d_{b}\, t\, F_{u} \right), \qquad \phi = 0.75 [math]
[math] l_{c1} = L_{e} – \frac{d_{h}}{2} \qquad l_{c2} = s – d_{h} [math]
The edge bolt has the short clear distance [mathin] l_{c1} [mathin], so tear-out usually limits it, while the inner bolts reach the 2.4 d t Fsen rulman kapağı. Check every ply: the plate or angles, and the beam web. A thin beam web is often the weak ply, because the angles or plate are sized independently. In the double angle example the two 1/4 in angles give 0.5 in of steel against the bolts, fakat 1/4 in beam web has only one ply, and bearing on the web is the highest strength ratio, -de 0.760.
Each bolt then delivers the least of its shear, bearing and tear-out strengths, ve grup gücü toplamıdır (J3.6 Açıklama):
[math] \phi R_{n,eff} = \frac{C}{n} \sum_{i=1}^{n} \min\left( \phi r_{v},\ \phi r_{n,plate,i},\ \phi r_{n,web,i} \right) [math]
4. Blok kesme (J4.3)
A block of the plate, angle or coped beam web can tear out around the bolt group: shear along the line of holes plus tension across to the free edge, usually an L-shaped block.
[math] \phi R_{n} = \phi \left( 0.6\, F_{u} A_{nv} + U_{bs} F_{u} A_{nt} \right) \le \phi \left( 0.6\, F_{y} A_{gv} + U_{bs} F_{u} A_{nt} \right), \qquad \phi = 0.75 [math]
[mathin] U_{bs} = 1 [mathin] when the tension stress is uniform, which is the case for a single line of bolts. The net areas deduct each hole at [mathin] d_{h} + 1/16\,in [mathin] for damage during punching (B4.3). In the shear end plate example, block shear of the plate is the second highest ratio, -de 0.920.
5. Shear yielding and shear rupture (J4.2)
The plate or angles carry the whole reaction in shear, across the gross section (verimli) ve ağ bölümü boyunca deliklerden (yırtılma):
[math] \phi R_{n} = \phi\, 0.6\, F_{y}\, A_{gv}, \qquad \phi = 1.00 [math]
[math] \phi R_{n} = \phi\, 0.6\, F_{u}\, A_{nv}, \qquad \phi = 0.75 [math]
In the single plate example, kesme kopması 1/2 in plate is the highest load check, -de 0.629.
6. Plate flexure and the shear-flexure interaction
The reaction acts at a distance from the support, so a single plate is a short cantilever. SkyCiv checks it with the Manual’s double-coped beam procedure, which treats the plate like a beam web coped top and bottom, and checks flexural rupture on the net section through the holes. Because the same section carries shear and moment, the two combine:
[math] \left( \frac{V_{u}}{\phi V_{n}} \right)^{2} + \left( \frac{V_{u}}{\phi R_{n}} \right)^{2} \le 1.0 [math]
This check grows with the eccentricity. In the conventional shear tab it is minor, but in the extended single plate example the rupture interaction governs the connection at 0.938.
7. Süneklik: the maximum plate thickness (Manuel Parça 10)
A shear connection is assumed to rotate. Plaka bükülmede cıvataların kesmede olduğundan daha güçlüyse, the bolts break before the plate yields, which is a brittle failure and contradicts the simple connection assumption. The Manual caps the plate thickness so the plate yields first:
[math] M_{max} = \frac{F_{nv}}{0.90}\, \frac{\pi}{4} d_{b}^{2}\, C’ [math]
[math] t_{max} = \frac{6\, M_{max}}{F_{y}\, d_{p}^{2}} [math]
C’ is the bolt group coefficient for moment alone. This is the one check that a thicker plate makes worse. In the single plate example a 1/2 in plate sits at 0.966 of its limit.
8. Weld strength and the base metal limit (J2.4, Manuel Parça 9)
The fillet welds that join the plate or angles to the support (or the end plate to the beam web) carry the reaction along their length:
[math] \phi R_{n} = \phi\, 0.6\, F_{EXX}\, \frac{\sqrt{2}}{2}\, w\, L_{w} \left( 1 + 0.5\, \sin^{1.5}\theta \right), \qquad \phi = 0.75 [math]
For a vertical reaction on vertical welds, [mathin] \theta = 0 [mathin] and the directional factor is 1.0. The steel either side of the weld also limits how much of the weld size counts. For welds on both faces of a plate of thickness t, on altıncılarda kullanılabilir boyut:
[math] D_{max} = \frac{ \frac{t}{2}\, F_{u} }{3.09\,kip/in} [math]
So a bigger weld does not always help. In the shear end plate example the 0.355 in beam web limits the usable weld to about 0.233 içinde, and the weld governs the connection at 0.995. For a single plate, the Manual also asks for fillets of [mathin] \frac{5}{8}\, t_{p} [mathin] her iki tarafta, so that the weld can develop the plate if it yields. Şuradaki boyutları deneyin: kaynak hesaplayıcı.
9. The supporting and supported members
The connection is only as good as the steel it attaches to. A coped beam has a reduced section at the cope, which needs its own block shear, shear and flexure checks; the single angle example works these through for a W12x14 coped at the top flange. Where the beam frames into a girder web or a thin column web, check bearing and tear-out on that web too.
Shear connection design examples (AISC 360-16 LRFD)
Aşağıdaki her örnek, SkyCiv Connection Design'ın tam bir AISC hesaplama tablosudur, her denklemle adım adım yazılmıştır, ikame değer ve DCR. They show how the governing check moves from one connection type to the next.
| Misal | Üyeler ve yük | Bağ | Governing load check |
|---|---|---|---|
| Tek plaka (kesme sekmesi) | W18x35 beam to W14x90 column flange, 50 kip | 1/2 tabakta, üç 1 A490-N cıvatalarında | Plate shear rupture, 0.629 |
| Çift açı | W16x26 beam to W14x90 column flange, 50 kip | 2L4x3-1/2×1/4, three rows of 3/4 in A325-N each side | Kiriş ağındaki cıvata yatağı, 0.760 |
| Tek açılı | Coped W12x14 beam to W18x35 girder web, 20 kip | L4x3x3/8, two rows of 3/4 in A325-N each leg | Bolt shear at the girder, 0.901 |
| Extended single plate | W24x55 beam to W14x90 column web, 100 kip | 3/8 x 13 x 21 A36 plakalı, on dört 3/4 A325-N'de | Kesme ve eğilme etkileşimi (yırtılma), 0.938 |
| Shear end plate | W18x50 beam to W14x90 column flange, 150 kip | 5/16 x 8 1/2 x 15 A36 plakalı, ten 3/4 A325-N'de, 1/4 in fillets | Weld at the beam web, 0.995 |
Desen bilmeye değer. A short, conventional shear tab is rarely close to its limit. Once the reaction moves away from the bolts, as in the single angle and the extended plate, the eccentricity drives the design. And in a welded connection like the end plate, the thinnest piece of base metal decides the weld.
For the theory behind all five, görmek AISC kullanarak çelik bağlantıların tasarımı 360-16.
Which shear connection should you use?
| Bağ | Şunun için en iyisi: | Dikkat et |
|---|---|---|
| Tek plaka (kesme sekmesi) | Most beam-to-column and beam-to-girder framing. One shop weld, one field bolt group | Plaka sünekliği (tmax), and the Table 10-9 limits on the conventional configuration |
| Extended single plate | Framing into a column web between the flanges, without coping the beam | Full eccentricity, plate flexure and the shear-flexure interaction |
| Çift açı | Heavier reactions, and erection where the beam needs to be dropped in between supports | Bearing on a thin beam web, and two bolt groups to detail |
| Tek açılı | Light reactions, and access from one side only | Eccentricity at the support bolts, which cuts the group strength |
| Shear end plate | Shop-welded beams with fast, tamamen cıvatalı saha montajı | Doğru ışın uzunluğu, and the weld limited by the beam web thickness |
Yazılım neyi kontrol ediyor??
For a shear connection, the design runs both a detailing pass and a strength pass.
Detailing runs first and catches the geometry: cıvata kenar mesafeleri, cıvata aralığı (adım ve ölçü), takım açıklıkları, and minimum and maximum plate dimensions, artı plakalar arasında çatışma tespiti, cıvatalar ve kaynaklar. A connection that fails here never reaches the solve. That is usually what you want, because the numbers do not matter if the detail cannot be built.
The strength checks then cover every limit state in the procedure above: bolt shear by ICOR, cıvata yatağı ve yırtılma, blok kesme kopması, kesme akması ve kopma, plate flexure and its interaction with shear, süneklik, and weld strength with the base metal limit, plus the checks on coped beams and the supporting member. The calculation report shows every formula, tam tasarım kontrolü ve kod referansı, with the clause numbers from AISC 360-16 veya AS 4100:2020, böylece hesaplamaya güvenmek yerine takip edebilirsiniz. Yukarıda üzerinde çalışılan örnekler bu raporlardan yazılmıştır..
For the fastener side of this, ilgili belgelere bakın cıvatalar ve kaynaklar.
Kesme ve Moment Bağlantısı arasındaki fark nedir??
A shear connection transfers shear only. A moment connection also transfers bending. Think of it as a menteşe: a shear connection lets the beam end rotate, a moment connection holds it.
The distinction is a decision about the analysis model, not only about the detail. A shear tab designed as simple has to be flexible enough to actually rotate, which is what the ductility check enforces, and a moment connection has to be stiff enough to justify the fixity the frame model assumed.
| Kesme Bağlantısı | Moment Bağlantısı | |
|---|---|---|
| Aktarılan Kuvvetler | Sadece Kesme | Kesme ve Moment |
| Alternatif isimler | Sabitlendi, Menteşe, Basit | Sert, Sabit, Anı dirençli |
| AISC 360-16 terim | Basit bağlantı | FR veya PR moment bağlantısı |
| Rotasyon | Döndürmeye İzin Verir | Restrains Rotation |
| Yazılım Sabitleme Kodu | FFFFFR | FFFFFF |
Sıkça Sorulan Sorular
How do you calculate the capacity of a shear connection?
Work out the strength of every limit state along the load path (bolt shear with the eccentricity, bearing and tear-out on each ply, blok kesme, kesme akması ve kopma, plaka bükülmesi, ductility and the welds) and take the lowest. That lowest value is the connection capacity, and the check that gives it is the governing limit state.
Is a shear connection the same as a pinned connection?
Evet, for analysis. A shear connection is modelled as a pin, free to rotate and carrying no moment. In practice it does carry a small moment, bu yüzden AISC 360-16 B3.4 asks that a simple connection have enough rotation capacity to accommodate the beam end rotation. The ductility limit on plate thickness is one way the design makes sure of that.
What is the eccentricity in a shear tab, and why is it a/2?
AISC Manuel Tablosu 10-9 geleneksel tek plakalı bağlantı için tasarım eksantrikliğini ayarlar. For many bolt counts and hole types it is half the distance from the weld line to the bolt line, a/2, because the point of zero moment sits between the weld and the bolts. Outside the conventional limits, such as a plate extended into a column web, the full distance is used and the bolt group loses much more strength.
Which check usually governs a shear connection?
It depends on the type. In the five worked examples the governing load check was plate shear rupture (tek plaka), kiriş ağındaki yatak (çift açı), bolt shear with eccentricity (tek açı), the shear-flexure interaction (extended single plate) and the weld (shear end plate). Thin beam webs and eccentricity are the two things to look at first.
Should the bolts be bearing type or slip-critical?
Most shear connections use snug-tight bearing-type bolts (A325-N, A490-N), which is what all five worked examples use. Slip-critical bolts are needed where slip would be a problem, such as oversized or slotted holes parallel to the load, or joints subject to fatigue or load reversal.
Can I design a shear connection with ASD instead of LRFD?
Evet. The limit states are identical. Değiştir [mathin] \phi R_{n} [mathin] ile [mathin] R_{n} / \Omega [mathin] and compare against the ASD reaction. SkyCiv Bağlantı Tasarımı her ikisini de çalıştırır, ve bunlar arasında geçiş yapmak bir ayardır.
Örnekler AISC 15. veya 16. baskı Kılavuzuna uygun mu??
AISC'yi takip ediyorlar 360-16 ve AISC Kılavuzu 15. Baskı, bu Şartnamenin etrafında yazılı olan. 16. Baskı Kılavuzu AISC ile eşleşiyor 360-22. The shear connection limit states are much the same, ancak yan tümce ve tablo referansları hareket ediyor, bu nedenle bunları projenizin kullandığı sürümle karşılaştırın.
SkyCiv Bağlantı Tasarım Yazılımı
Yukarıdaki modeller ve kontroller SkyCiv Bağlantı Tasarımı. Üzerini kapsıyor 80+ önceden yapılandırılmış bağlantı türleri, AISC'ye göre tasarımlar 360-16 (LRFD & ASD) ve benzeri 4100:2020, ve her formülü gösterir, tam tasarım kontrolü ve kod referansı.
Bağlantıyı 3 boyutlu olarak modelleyebilirsiniz, cıvataları değiştir, yük verilerinizi kaybetmeden kaynaklar veya plakalar, CloudCAD'de 2D detay çizim sayfaları oluşturun, ve Revit'te koordinasyon için 3D geometriyi IFC'ye aktarın, Tekla veya Navisworks.
Tamamen tarayıcıda çalışır, indirmesiz, güncellemeler veya BT kurulumu.
Tam modül, adım adım hesaplama raporunu ekler, yukarıdaki çalışılan örnekler gibi, her kapasite ve DCR ile.
Referanslar
- AISC 360-16, Kullanıcı iş akışını basitleştirmek ve hızlandırmak için UI İyileştirmeleri: B3.4, B4.3, J2.4 (Eşitlik. J2-4), J3.2 (Tablo J3.2), J3.3, J3.4 (Tablo J3.4), J3.5 (Tablo J3.5), J3.6 (Eşitlik. J3-1) ve Yorum, J3.10 (Eşitlik. J3-6a, J3-6c), J4.2 (Eşitlik. J4-3, J4-4), J4.3 (Eşitlik. J4-5).
- AISC Çelik Konstrüksiyon Kılavuzu, 15th Baskı: Bölüm 7 (Eşitlik. 7-1, anlık dönme merkezi); Bölüm 9 (kaynak boyutunda ana metal sınırı, coped beam flexure); Bölüm 10 (simple shear connections, Tablo 10-9, Eşitlik. 10-3 ve 10-4).
- GİBİ 4100:2020, Çelik Yapılar.
Harold Munalem
Ürün Müdürü, Bağlantı Tasarımı
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