Saimaa University of Applied SciencesTechnology, LappeenrantaDouble Degree Programme in Civil and Construction EngineeringCivil EngineeringFilipp PopovDesign of prefabricated steel structures equippedwith a jib crane for auxiliary purposesBachelor’s Thesis 2019

AbstractFilipp PopovDesign of prefabricated steel structures equipped with a jib crane for auxiliarypurposes34 pagesSaimaa University of Applied SciencesTechnology, LappeenrantaDouble Degree Programme in Civil and Construction EngineeringCivil EngineeringBachelor’s Thesis 2019Instructors: Petri Himmi, senior lecturer, Saimaa University of Applied Sciences,Mika Myllys, PrePipe OyThe aim of this work was to test the possibility of developing a quick-assembledsteel structure that uses shipping containers as a base and it equipped with twodiagonally located cranes for production needs. The demand for such designs ishigh due to the ability to mobilize production and quickly deploy it in anylocation. However, the market does not have all the available options of suchconstruction designs, therefore, in this work, a variant of such a design will bedeveloped, which aims to cover all the strength characteristics to be used in alarge list of locations in Finland.The construction of the building is designed in accordance with the Eurocode.Keywords: steel construction, fast-assembling, jib crane, limit state designmethod, light-weight steel construction, structural analysis.2

Table of Contents1 Introduction . 42 Theoretical part . 53 Preliminary design stage . 64 Loads evaluation . 84.1 Self-weight of the construction . 84.2 Snow load . 104.3 Wind load . 114.4 Jib cranes load. 205 Structural analysis . 235.1 Analysis method . 235.2 Load combinations. 235.3 Assessment of the bearing capacity of profiled sheeting . 245.4 Cantilever crane plate connection analysis . 275.5 Selection of the thickness of the base plate . 305.6 Complete structural analysis . 326 Conclusion . 34References . 343

1 IntroductionThe main aim of this thesis work is to develop a design that would satisfy productiontasks as well as Eurocode norms and standards. This thesis contains full stages of thesteel structures design from the preliminary concept of the project to the detaileddrawings that are necessary for the preparation of materials in the factories, and thenfor the erection of the construction on site. One of the main requirements for such kindof construction is quick assembling. That means, this project excludes welded jointscarried out at the installation stage, as well as work associated with concrete elements.All connections are provided with bolts. All shipping marks correspond to the overalldimensions of transportation.Load calculations and structural analysis methods were provided in accordance with theEurocode.In addition, this thesis considered modern methods of building design relatedto the use of special software equipment, which can significantly simplify the designingprocess.4

2 Theoretical partThe main goal of the theoretical part is to briefly describe types of structural solutionsthat are possible to use during the design process. For the project we could use threeprincipal schemes that are described below:1) Spatial framework using a hinged truss as a roof support structure.2) Spatial framework using a composite beam as a roof support structure, (Thisbeam is divided into two shipping marks, which are connected by means of aflange connection form a duo-pitch roof frame).3) Spatial framework using a rigidly connected beam that formed a supportstructure for the mono-pitch roof envelope.Constructions described above are the most common when implementing similarprojects. Based on the features of our terms of the designed task, from the list ofsolutions presented, we would choose the most suitable for our case.Since trusses are more suitable for long-span structures using such kind of aconstructive solution would lead to the unreasonable increasing in the project’s steelconsumption and the weight of the structure would be significantly exaggerated too.Thus, using a truss as a roof supporting structure is not the best solution. Also, using acomposite beam may cause a few problems with on-site flange connectionimplementation because such type of connection requires an accurate fit of the surfacesto be joined. This way, a scheme with a mono-pitch roof construction solution would bethe most suitable to meet the requirements of the project (fast-assemblying, costeffective, easy to implement).Previously, the supporting elements will be made of prefabricated structures (twistlocks) while the base of the columns will be connected by a traverse to simplifyinstallation and transportation (also vertical ties which unfastening the columns from theplane and preventing a general loss of stability will be welded to the structure at thefactory too). Thus, column, traverse and vertical ties would form a truss. This way it isnecessary to avoid the appearance of a load outside their transmission points to avoidthe occurrence of additional bending moments.For this, the fastening of the roof beams will be carried out through the nodes locatedabove the columns.The connection will be carried out using bolts for correct separation at the shippingmarks. Also, it is necessary to remember the accuracy of assembly of this structure andprovide oversized holes for bolts.5

3 Preliminary design stageOn this stage, the overall dimensions of the structure are determined, structural solutionsare considered, and design schemes are drawn up for future structural analysis. In thefuture process of designing constructional solutions may change. The main task of thisstage is to determine the purpose and main dimensions of the structure, draw up apreliminary model intended for further calculation.In our case we will use the 3D AutoCAD software to draw the calculation scheme andexport the DXF file that will be used in structural analysis software to calculate the loadcombinations.Figure 3.1 Design scheme (Autodesk AutoCAD student’s version)Thus, the main parameters of the future construction:1. Length in lay-out: 6058 mm (including the 20ft shipping container that used asbasement), 5600 mm (frame of the construction).2. Width in lay-out: 11868 mm (including the 20ft shipping container that used asbasement), 7000 mm (frame of the construction).3. Height: 5990 (including the 20ft shipping container that used as basement), 3400mm (frame of the construction).6

4. Roof slope angle: 8 .5. Column pitch: 2800 mm.6. Bulk pitch: 1415 mm.These dimensions are given as reference. In the process of calculation, they can varyslightly, if the technical specifications allow and there is no restriction on dimensions. Inour case, the height of the structure is not limited (however, excessive overestimation orunderstatement will lead to irrational consumption of material and complications duringtransportation). Also, it should be remembered that the structure is equipped with cranesthat must work independently and not complicate the procedure of unloading or loadingmaterials onto vehicles. The length and width of the structure is limited by the size of theshipping marks and the size of the shipping containers that are used as the base.Thus, the design scheme represents the dimensions of the designed structure with slightdeviations that are considered in the calculation.Since the enclosing structure will be a profiled flooring that requires fastening to thestructure through self-tapping screws, secondary coating beams should be located withthe frequency with which it will be easy to mount the profiled flooring. Secondary beamsalso play the role of unfastening elements, preventing the loss of stability of the main roofbeams and twisting of the structure at all.7

4 Loads evaluation4.1 Self-weight of the constructionDead load of the columns and truss elements is calculated using Robot StructuralAnalysis software, in accordance with the designated sections of the elements of theframe, columns. The cross-sectional dimensions are determined by their geometriccharacteristics, as well as based on design experience.Calculation of the dead load of the roof covering structure is given below:Figure 4.1.1 Load distribution by dead weight (Autodesk AutoCAD student’s versiondrawing)Distributed over area load occurred by dead load of the roof envelope and snow couldbe represented as distributed over the element’s (horizontal supporting beam in ourcase) length.The roof envelope structure is implemented with Ruukki load bearing sheet T45-30L905 with 0,7 mm thickness and nominal weight of the m2 — 7,59 kg (0,076 kN/ m2). This8

is not a final decision because the final version of the coverage will be selected from thecondition of checking for limit states when a load (calculated further) is applied to it.Thus, load distributed over the length of the beam :𝐺𝐺𝑘𝑘 𝑔𝑔𝑘𝑘 𝑎𝑎 0,076Where:𝑘𝑘𝑘𝑘𝑚𝑚2 1,414 𝑚𝑚 0,107 𝑘𝑘𝑘𝑘/𝑚𝑚(4.1.1)𝑔𝑔 distributed dead load, kN/m2;𝑎𝑎 influence area dimention, m.As for the edge elements, for them distributed over length load would be two time lessbecause of the smaller influence area.Figure 4.1.2 Influence area of one beam (Autodesk AutoCAD student’s version drawing)9

4.2 Snow loadSnow load calculation is provided in accordance with EN 1991-1-3 [1] and FinnishNational Annex 4 [6].In this calculation one snow distribution scheme is determined because of theconstruction of the mono-pitch roof.Snow load calculated by using formula:(4.2.1)𝑆𝑆 𝜇𝜇𝑖𝑖 𝐶𝐶𝑒𝑒 𝐶𝐶𝑡𝑡 𝑆𝑆𝑘𝑘Where 𝜇𝜇𝑖𝑖 – is the snow load shape coefficient;Ce – is the exposure coefficient;Ct – is the thermal coefficient;Sk – is the characteristic value of snow load on tile ground.In our case, the value Sk would be taken as the biggest value between several districtsaround Lappenranta city location because of the construction’s mobility. Thus, the Skvalue would be 2.75 kN/m2 in accordance with Finnish National Annex 4 [6].This value of the snow load is optimal, since it will not lead to excessive metalconsumption in view of the irrational choice of the material section when usingexcessive snow load. However, in view of the small size of the projected object, it isrecommended to avoid the formation of significant snow formations on the roofstructure.The exposure coefficient and thermal factor could be taken: 𝐶𝐶𝑒𝑒 1, 𝐶𝐶𝑡𝑡 1.In our case, it does not involve the use of special heating equipment that cansignificantly affect the melting of snow in the roof area, which will lead to a decrease inthe snow load. As for the snow transfer coefficient, its value is taken as the maximum inview of the formation of the reserve of bearing capacity during the operation of thestructure𝜇𝜇1 0,8 – for the slope angle 8 due to the table 4.2.1This angle of inclination is selected based on considerations of economic efficiency ofmaterial consumption as well as the need to form the proper slope to removeprecipitation from the roof structure10

Table 4.2.1: Snow load shape coefficient (SFS-EN 1991-1-3. Table 5.2)Snow load evaluation:𝑆𝑆 0,8 1 1 2,75 2,2 𝑘𝑘𝑘𝑘/𝑚𝑚2This way, the length distributed value of the snow load would be:𝑆𝑆 2,2 𝑘𝑘𝑘𝑘/𝑚𝑚2 1,414 𝑚𝑚 cos (8 ) 3,08 𝑘𝑘𝑘𝑘/𝑚𝑚Figure 4.2.1 Snow load shape coefficients (SFS-EN 1991-1-3. Figure 5.2)4.3 Wind loadDetermination of the basic wind velocity:(4.3.1)𝑣𝑣𝑏𝑏 𝐶𝐶𝑑𝑑𝑑𝑑𝑑𝑑 ��𝑠 𝑣𝑣𝑏𝑏,0Where:𝑣𝑣𝑏𝑏 – basic wind velocity;𝐶𝐶𝑑𝑑𝑑𝑑𝑑𝑑 – directional factor;11

��𝑠 – seasonal factor;𝑣𝑣𝑏𝑏,0 – fundamental falue of the wind velocity.In our case:𝑣𝑣𝑏𝑏,0 0,21 𝑚𝑚/𝑠𝑠 in accordance with Finnish National Annex 5 [7].Terrain category: IIIIn our case, this type of terrain was selected on the basis of the assumption that thedesigned structure will be used mainly for production purposes (meaning the prevailinglocation of such a building is the enclosed territory of a construction or industrial site).Consequently, the proposed type of terrain will exclude direct wind exposure typical of acompletely open or coastal terrain, since buildings of this purpose involve the use offencing required by safety considerations for built-up areas and areas of industrialbuildings.z0 3;zmin 5 in accordance with EN 1991-1-4 [2];𝐶𝐶𝑑𝑑𝑑𝑑𝑑𝑑 1 as recommended in EN 1991-1-4 ��𝑠𝑠 1 as defined in 4.2 (2) EN 1991-1-4 [2].𝑣𝑣𝑏𝑏 1 1 21 21 𝑚𝑚/𝑠𝑠Determination of the basic velocity pressure:(4.3.2)𝑞𝑞𝑏𝑏 0,5 𝜌𝜌 𝑣𝑣𝑏𝑏 2Where:𝑞𝑞𝑏𝑏 – basic velocity pressure.𝑣𝑣𝑏𝑏 – basic wind velocity;𝜌𝜌 – density of the air (1,25 kg/m3 as recommended in Finnish National Annex 5 [7]);𝑞𝑞𝑏𝑏 0,5 1,25 212 0,28 𝑘𝑘𝑘𝑘/𝑚𝑚2Determination of the peak velocity pressure:(4.3.3)2𝑞𝑞𝑝𝑝 [1 7𝑙𝑙𝑣𝑣 ] 0,5 𝜌𝜌 𝑣𝑣𝑚𝑚Where:𝑞𝑞𝑏𝑏 – peak velocity pressure.𝑣𝑣𝑚𝑚 – mean wind velocity;𝜌𝜌 – density of the air;𝑙𝑙𝑣𝑣 – turbulence intensity.Calculation of the mean velocity pressure:𝑣𝑣𝑚𝑚 𝑐𝑐𝑟𝑟 𝑐𝑐 𝑣𝑣𝑏𝑏(4.3.4)12

Where:𝑐𝑐𝑟𝑟 – roughness factor;𝑐𝑐𝑜𝑜 – orography factor (co 1 in our case).𝑧𝑧(4.3.5)𝑐𝑐𝑟𝑟 𝑘𝑘 𝑇𝑇 ln ( )𝑧𝑧0Where:kT – terrain factor, depending on the roughness length.Calculation of the mean velocity pressure:𝑘𝑘 𝑇𝑇 0,19 ln 0,07 )𝑧𝑧0,𝐼𝐼𝐼𝐼 0,05 (terrain category II);𝑧𝑧0 0,3 (terrain category III).Calculation of the turbulence intensity:𝑙𝑙𝑣𝑣 𝑘𝑘𝐼𝐼(4.3.7)𝑧𝑧𝐶𝐶0 𝑙𝑙𝑙𝑙 𝑧𝑧 Where:0kI – turbulence factor (kI 1, as recommended in EN 1991-1-4 [2]);z 6,00 m in our case.Thus,𝑞𝑞𝑝𝑝 1 1 7𝑘𝑘𝐼𝐼𝑧𝑧𝑐𝑐0 𝑙𝑙𝑙𝑙 𝑧𝑧 7 10 𝑞𝑞𝑏𝑏 0,19 ( 280 0,19 (61 𝑙𝑙𝑙𝑙 0,3 𝑧𝑧0𝑧𝑧0,𝐼𝐼𝐼𝐼0,3 0,07)0,05External pressure coefficients:𝑧𝑧)0,07 ) 𝑙𝑙𝑙𝑙 𝑧𝑧0) 𝑙𝑙𝑙𝑙 0,3 0,946 kN/m2;0,05(4.3.8)𝑤𝑤𝑒𝑒 𝑞𝑞𝑝𝑝 (𝑧𝑧𝑒𝑒 ) 𝑐𝑐𝑝𝑝𝑝𝑝Where:𝑧𝑧𝑒𝑒 – reference height of the external pressure;𝑐𝑐𝑝𝑝𝑝𝑝 - pressure coefficient for the external pressure depending on the size of the loadedarea (in our case cpe,10, because the loaded area for the structure is larger than 10m2).For vertical walls:h b;e min(b,2h) min (5,6; 6) 5,6;13

e d 7 m (11 m);Figure 4.3.1 Key for vertical loads (SFS-EN 1991-1-4. Figure 7.5)Plan view:Figure 4.3.2 Zone plan for the vertical wall loads definition(SFS-EN 1991-1-4 Figure 7.5)14

To determine pressure coefficents in each zone it is necessery to know the h/d value.Coefficients value is given in the table:Table 4.3.1 Recommended values of external pressure coefficients for vertical walls ofrectangular plan buildings (SFS-EN 1991-1-4 Table 7.1)In our case:h/d 6,00/7,00 0,86Thus, the following coefficients cpe,10 should be chosen:Zone A: -1,2Zone B: -0,8Zone C: -0,6Zone D: 0,8Zone E: -0,5For monopitch roofs:In accordance with our design scheme pitch angle 8 , such case is not shown in thetable below. Thus, as recommended linear interpolation method used.When wind direction angle θ 0 :e min(b;2h), where b – is crosswind dimention.In our case e min(5,60 m; 12,00 m) 5,60 m.The following coefficients should be chosen:Zone F: -1,46; 0,06;Zone G: -0,8; 0,06;Zone H: -0,3; 0,06.When wind direction angle θ 180 :e min(b;2h), where b – is crosswind dimention.In our case e min(7,00 m; 12,00 m) 7,00 m.The following coefficients should be chosen:15

Zone F: -2,36;Zone G: -1,3;Zone H: -0,83Figure 4.3.3 Zone plan for the mono-pitch roofs loads definitionwith wind direction angle θ 0 and θ 180 (SFS-EN 1991-1-4 Figure 7.7)When determining the influence area of the bearing elements, it should be rememberedthat vertical ties, half-timbers and other minor non-bearing elements do not perceive thewind load transmitted through the building envelope.Thus, only the main parts of the building frame, namely columns, will participate in theload perception.Linear interpolation coefficients were chosen from the table shown below.16

Table 4.3.2 Recommended values of external pressure coefficients for monopitch roofs(SFS-EN 1991-1-4 Table 7.3a)When wind direction angle θ 90 :e min(b;2h), where b – is crosswind dimention.In our case e min(7,00 m; 12,00 m) 7,00 m.Figure 4.3.4 Zone plan for the duo-pitch roofs loads definitionwith wind direction angle θ 90 (SFS-EN 1991-1-4 Figure 7.7)17

The following coefficients should be chosen:Zone Fup: -2,19;Zone Flow: -1,95;Zone G: -1,83;Zone H: -0,66;Zone I: -0,56;All coefficients are chosen in accordance with the table:Table 4.3.3 Recommended values of external pressure coefficients for duopitch roofs(SFS-EN 1991-1-4 Table 7.3b)Internal pressure coefficients:𝑤𝑤𝑖𝑖 𝑞𝑞𝑝𝑝 (𝑧𝑧𝑖𝑖 ) ��� – reference height of the internal pressure;𝑐𝑐𝑝𝑝𝑝𝑝 - pressure coefficient for the internal pressure.The internal pressure coefficient depends on the size and distribution of the openings inthe building envelope.18

In our case cpi taken as the more onerous of 0,2 and - 0,3 as recommendedin SFS-EN 1991-1-4 [3]. Such a decision was made because the structure should beable to be operated with different permeability levels of the building envelope (partlycovered during the summer period or with enclosed building envelope during winter timeor in case of extra precipitations in order to create more comfortable working conditionsduring the facility using period). In our case value cpi 0,2 would be more unfavorablethan cpi -0,2.Thus, the wind load per unit length (horizontal beam, vertical column in our case) wouldbe determined as:𝑤𝑤 𝑞𝑞𝑝𝑝 (𝑐𝑐𝑝𝑝𝑝𝑝 𝑐𝑐𝑝𝑝𝑝𝑝 ) 𝑎𝑎(4.3.10)Where 𝑤𝑤 – is the wind load;𝑞𝑞𝑝𝑝 – is the peak velocity pressure;𝑐𝑐𝑝𝑝𝑝𝑝 – pressure coefficient for the internal pressure;𝑐𝑐𝑝𝑝𝑝𝑝 – pressure coefficient for the external pressure;𝑎𝑎 influence area dimention, m (1,414 m for the horizontal beams (0,717 m for theedge beams) and 2,800 m for the vertical elements (1,400 for the edge ones). Inaddition, according to pressure wind load pressure distribution occurring on horizontalmounting beams reduce the internal stresses of the beam. Therefore, they may not beconsidered in load combinations in order to increase the safety margin.This way, the wind load will be considered when it acts on the vertical components ofthe structure (bearing trusses and cover trusses).The load distribution by the influence width would be:1) Load case with wind direction angle θ 0 :For the windward side:𝑤𝑤 0,946𝑤𝑤 𝑚2 0,8 2,8 𝑚𝑚 2,12 𝑘𝑘𝑘𝑘/𝑚𝑚 0,8 1,4 𝑚𝑚 1,06 𝑘𝑘𝑘𝑘/𝑚𝑚(For the central column);(For the edge columns);In the case of a load from the windward side, the internal pressure coefficient reducesthe influence of wind pressure on structural elements from the windward side; therefore,it is not considered to increase the margin of safety.For the leeward side:𝑤𝑤 0,946𝑤𝑤 𝑚2 (0,6 0,2) 2,8 𝑚𝑚 2,12 𝑘𝑘𝑘𝑘/𝑚𝑚 (0,6 0,2) 1,4 𝑚𝑚 1,06 𝑘𝑘𝑘𝑘/𝑚𝑚19(For the central column);(For the edge columns);

2) Load case with wind direction angle θ 180 :For the windward side:𝑤𝑤 0,946𝑤𝑤 𝑚2 0,8 2,8 𝑚𝑚 2,12 𝑘𝑘𝑘𝑘/𝑚𝑚 0,8 1,4 𝑚𝑚 1,06 𝑘𝑘𝑘𝑘/𝑚𝑚(For the central column);(For the edge columns);For the leeward side:𝑤𝑤 0,946𝑤𝑤 𝑚2 (0,6 0,2) 2,8 𝑚𝑚 2,12 𝑘𝑘𝑘𝑘/𝑚𝑚 (0,6 0,2) 1,4 𝑚𝑚 1,06 𝑘𝑘𝑘𝑘/𝑚𝑚(For the central column);(For the edge columns);3) Load case with wind direction angle θ 90 :For the side facades:𝑤𝑤 0,946𝑤𝑤 𝑚2 (0,8 0,2) 2,8 𝑚𝑚 2,8 𝑘𝑘𝑘𝑘/𝑚𝑚 (1,2 0,2) 1,4 𝑚𝑚 1,96 𝑘𝑘𝑘𝑘/𝑚𝑚(For the central column);(For the edge columns (for bothexternal pressure coefficient -1,2 was chosen in order to increase safety margin)).In these two cases, the wind pressure acting on the vertical elements of the coveringtrusses is not considered due to its insignificant effect.4.4 Jib cranes loadIn the project following the model of the jib crane would be used:«Seinäkääntö SKA 250 kg» with jib length 3,000 m and maximum lifting weigth 250 kg.In accordance with technical task two such cranes would be attached at two diagonallyopposite corners of the conctruction to increase productivity and independence of use.The crane will be mounted to the steel plate using high-strength bolts. The steel platewould be welded to the vertical bearing element. The choice of such a crane is the mostoptimal for our situation and represents the best ratio of self-weight and load capacity.Also such cranes are the simplest during installation and commissioning. Another plusof choosing such a crane is the independence of the work of two opposite parts of thestructure (located on two different containers). Unlike an overhead crane, where a smalldifference in the unevenness of the rail can cause additional loads, jib cranes are notsensitive to such cases and can be brought into working condition with much lowermounting accuracy.20

Figure 4.4.1 Jib crane drawing (Tuotetekno Oy cranes catalogue)Load occurred by the Jib crane:Load occurred by lifting goods and dead load of the crane construction (characteristicvalue):𝑄𝑄𝑘𝑘 𝑚𝑚 𝑚𝑚𝑠𝑠1 𝑚𝑚𝑠𝑠2 ;(3.4.1)Where:𝑄𝑄𝑘𝑘 characteristic load value, kN;𝑚𝑚 maximum lifting weight, N;In our case, due to the technical characteristics of the crane maximum lifting weight is250 kg 2,5 kN.𝑚𝑚𝑠𝑠1 weight of the crane’s jib, N; 𝑚𝑚𝑠𝑠1 67 kg 0,67 kN.𝑚𝑚𝑠𝑠2 weight of the crane’s plate, N; 𝑚𝑚𝑠𝑠2 23 kg 0,23 kN.Thus, load occurred by crane would be:𝑄𝑄𝑘𝑘 2,5 0,67 0,23 3,4 kN.Bending moment occurred by crane:(3.4.2)𝑀𝑀𝑘𝑘 𝑀𝑀𝑐𝑐 𝑀𝑀𝑗𝑗Where:𝑀𝑀𝑘𝑘 characteristic bending moment value, kN·m;𝑀𝑀𝑐𝑐 bending moment occurred by cargo lifting, kN·m;𝑀𝑀𝑗𝑗 bending moment occurred by crane’s jib, kN·m;21

The bending moment occurred by crane’s jib could be represented as dead loaddistributed by the jib’s length.𝑀𝑀𝑐𝑐 2,5 𝑘𝑘𝑘𝑘 3 𝑚𝑚 7,5 𝑘𝑘𝑘𝑘 𝑚𝑚;𝑀𝑀𝑗𝑗 0,66 𝑘𝑘𝑘𝑘 3 𝑚𝑚2 0,99 𝑘𝑘𝑘𝑘 𝑚𝑚;𝑀𝑀𝑘𝑘 7,5 𝑘𝑘𝑘𝑘 𝑚𝑚 0,99 𝑘𝑘𝑘𝑘 𝑚𝑚 8,49 𝑘𝑘𝑘𝑘 𝑚𝑚.These loads will be applied together depending on the location of the crane jib.22

5 Structural analysis5.1 Analysis methodIn this work, limiting states design method was used to select elements and analysetheir bearing capacity. This method of calculating the structure implies the presence ofgroups of limit states that the structure must satisfy. For this thesis, an analysis of thestructure was carried out according to structures two limiting states – ULS (UltimateLimit State) and SLS (Serviceability Limit State). ULS group includes stress and stabilityanalysis of the structure when SLS group includes deflection (in our case) as well asdurability and cracking analysis. Such a method of structural design was chosen inaccordance with rules and recommendations of EN-1990 [3] standard.5.2 Load combinationsLoad combinations were compiled in accordance with EN-1990 [3] general designprinciples as well as with Finnish National Annex rules that include necessaryinformation about load partial factor and combination factor values. The partial loadfactor depends on load (dead, live, snow, wind, seismic, etc.), combination (favourable,unfavourable) and analysis group (SLS or ULS). In our design case seismic, emergencyand temperature load cases application will not be considered in view of the features ofthe designed structure.Thus, the following coefficients were used in load combinations consideringconsequences class (CC2) of the designed facility.23

Table 5.2.1 Recommended values of combination and load partial factors(Autodesk Robot Structural Analysis editor of code regulation table)5.3 Assessment of the bearing capacity of profiled sheetingAs mentioned on the load evaluation part, some parts of the designed structure requireverification after assessing the loads. In our case, the «Ruukki» load bearing profiledsheet T45-30L-905 was pre-selected.T45-30L-905 properties (in accordance with manufacturer instruction):Width: 905 mm;Thickness: 0,7 mm;Nominal weight of the m2: 7,59 kg (0,076 kN/ m2);Steel yield strength: 350 MPa (S350 steel);Calculated properties (the calculation is based on the geometric characteristicsindicated on the manufacturer’s website):Moment of inertia (of one m): 29 cm4;Section modulus: 11,6 cm3.The design scheme in our case could be represented as a double span beam withmaximum moment on support. Also, it should be noted that the calculation is carried outon 1 m of profiled sheeting:𝑀𝑀 𝑞𝑞(𝑙𝑙 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐)28;(5.3.1)24

Where:𝑞𝑞 load value, kN/m;𝑙𝑙 span length, m;𝛼𝛼 roof slope angle;Thus, the design scheme can be represented as follows:Figure 5.3.1 Transformation of the calculation scheme (Lightweight metal structures.Calculation Examples)A uniformly distributed load will be composed of snow dead load, considering the loadpartial coefficients specified in the table

Also, it is necessary to consider the direction of action of the dead load and the spanlength when calculating a uniformly distributed load.This way, the uniformly distributed value could be represented:𝑞𝑞 1,5 𝑆𝑆 1,35 𝐶(𝛼𝛼)𝑞𝑞 uniformly disributed load value, kN/m;𝑙𝑙 span length, m;𝑔𝑔𝑘𝑘 dead load value, kN/m;𝑆𝑆 snow load value, kN/m;𝛼𝛼 roof slope angle;Thus:𝑞𝑞 1,5 2,2 1,35 0,076 3,4 kN/m;𝐶𝐶𝐶𝐶𝐶𝐶(8 )And the maximum bending moment value would be:𝑀𝑀 3,4 (1,414 0,99)28 0,83 𝑘𝑘𝑘𝑘 𝑚𝑚;Strength analysis of the profiled ���𝑊 𝛾𝛾 𝑢𝑢𝑚𝑚(5.3.3) 1;Where:𝑊𝑊 section modulus, cm3;𝑀𝑀𝑚𝑚𝑚𝑚𝑚𝑚 maximum bending moment, 0,83 𝑘𝑘𝑘𝑘 𝑚𝑚;𝑓𝑓𝑦𝑦 steel yield strength, MPa;𝛾𝛾𝑚𝑚 material properties partial factor;0,83 10335011,6 1 1;0,2 1 – section ok;Reducing the cross section is not usable because of design reasons.And maximum deflection could be represented using formula:𝛿𝛿 𝑞𝑞(𝑙𝑙 ���𝑥𝑥Where: 𝑙𝑙;(5.3.4)200𝛿𝛿 deflection, cm;𝑞𝑞 uniformly disributed load value, kN/m;𝑙𝑙 span length, m;𝐸𝐸 elasticity modulus, MPa;26

𝐼𝐼𝑥𝑥 moment of inertia, 29 cm4;In this case, uniformly distributed load should be represented as characteristic value:𝑞𝑞 1 𝑆𝑆 1 𝛿𝛿 𝑔𝑔𝑘𝑘𝐶𝐶𝐶𝐶𝐶𝐶(𝛼𝛼) 1 2,2 1 0,0228𝑘𝑘𝑘𝑘 (141,4 𝑐𝑐𝑐𝑐 0,99)4𝑐𝑐𝑐𝑐104 𝑘𝑘𝑘𝑘185 2,1 29𝑐𝑐𝑐𝑐4𝑐𝑐𝑐𝑐20,0760,99 0,08 𝑐𝑐𝑐𝑐 2,28 kN/m;140 𝑐𝑐𝑐𝑐200 0,7 𝑐𝑐𝑐𝑐;From this we can conclude that the selected profiled sheet is suitable for use in ourcase.5.4 Cantilever crane plate connection analysisIn this project, the cantilever jib crane would be fastened with high-strength bolts (asrecommended by the manufacturer) to the plate, which will be welded to the column.Thus, the strength capacity of such weld connection should be checked.Plate size: 370x740 mm;Plate material: S355;Weld fillet leg: 6 mm;Figure 5.4.1 Weld fillet characteristics (Materials&Welding website)The weld throat could be calculated as:𝑎𝑎 𝐿𝐿 𝐶𝐶𝐶𝐶𝐶𝐶(45 )(5.4.1)27

Where:𝐿𝐿 – weld fillet leg size, mm;a – weld fillet throat size, mm;𝑎𝑎 6 𝐶𝐶𝐶𝐶𝐶𝐶(45 ) 4,24 𝑚𝑚𝑚𝑚;This way, bearing capacity of weld ��𝑅 (5.4.2) 3 𝛽𝛽𝑤𝑤 ��𝑅 bearing capacity of weld fillet, kN/ cm2 ;𝑓𝑓𝑢𝑢 steel ultimate tensile sthrengh, kN/cm2;𝛽𝛽𝑤𝑤 correlation factor (EN1993-1-8) [4];𝛾𝛾𝑀𝑀2 material partial factor (EN1993-1-8) [4];47𝐹𝐹𝑤𝑤,𝑅𝑅𝑅𝑅 3 0,9 1,25 24 kN/cm2 ;The following forces would act at the attachment point:Shear forces:(5.4.3)𝑄𝑄 1,35 𝑄𝑄𝑘𝑘Where:𝑄𝑄𝑘𝑘 – characteristic load value, occurred by crane’s plate, jib and by lifting goods;Bending moments:𝑀𝑀 1,35 𝑀𝑀𝑘𝑘(5.4.4)𝑀𝑀𝑘𝑘 – characteristic bending moment value, occurred by crane’s jib and by lifting goods(bending moment occurred by crane’s plate is not significant and may not be taken intoaccount in our case);𝑄𝑄 1,35 3,4 4,59 𝑘𝑘𝑘𝑘;𝑀𝑀 1,35 8,49 11,46 𝑘𝑘𝑘𝑘 𝑚𝑚;Determine the geometric characteristics of the weld fillet cross section at the plate tocolumn attachment point:Moment of inertia:𝐽𝐽𝑥𝑥 𝑏𝑏𝑎𝑎3 𝑏𝑏1 𝑎𝑎13Where:12 12 75,23 1,08 74312 60557 𝑐𝑐𝑚𝑚4 ;(5.4.5)a,b,a1,b1 – external and internal sides of the weld contourArea of the welding fillet:𝐴𝐴 𝑙𝑙 𝑎𝑎 ;(5.4.6)Where:28

𝑙𝑙 total length of the weld fillet (subject to weld defects of 10 mm on each side);𝑎𝑎 – weld fillet throat size, mm;𝐴𝐴 2 (74 10,8) 0,42 71,2 𝑐𝑐𝑚𝑚2 ;Section modulus:𝑊𝑊𝑥𝑥 2 𝐽𝐽𝑥𝑥ℎ;(5.4.6)Where:𝐽𝐽𝑥𝑥 moment of inertia, cm4;ℎ cross section height, cm;𝑊𝑊𝑥𝑥 2 6055775,2 1610 𝑐𝑐𝑚𝑚3 ;Figure 5.4.2 Weld fillet cross section dimensions (Autodesk AutoCAD student’s versiondrawing)29

Weld fillet shear stress from bending moment:𝜏𝜏𝑀𝑀 𝑀𝑀𝑊𝑊𝑥𝑥Where:(5.4.7);𝑀𝑀 maximum bending moment, 𝑘𝑘𝑘𝑘 𝑚𝑚;𝑊𝑊𝑥𝑥 section modulus, 𝑐𝑐𝑚𝑚3 ;𝜎𝜎 11,46 1021610 0,7 kN/cm2 ;Weld fillet shear stress from shear force:𝑄𝑄(5.4.8)𝜏𝜏𝑄𝑄 ;𝐴𝐴Where:𝑄𝑄 maximum shear force, 𝑘𝑘𝑘𝑘;𝐴𝐴 weld fillet section area, 𝑐𝑐𝑚𝑚2 ;𝜏𝜏𝑄𝑄 4,59 0,06 kN/cm2 ;71,2Total stress in the weld fillet:2𝜏𝜏 𝑇𝑇 𝜏𝜏𝑄𝑄2 𝜏𝜏𝑀𝑀 0,062 0,72 0,7 𝑘𝑘𝑘𝑘/𝑐𝑐𝑚𝑚2 ;(5.4.9)The stresses ar

Design of prefabricated steel structures equipped with a jib crane for auxiliary purposes. Bachelor's Thesis 2019. 2 . Abstract . Filipp Popov . Load calculations and structural analysis methods were providedin accordance with the Eurocode.In addition, this thesis considered modern methods of building design related .