STRUCTURAL DESIGN REPORT -Steel bracings … DESIGN REPORT -Steel bracings removal- Fokker Logistics Park– Amsterdam, Netherlands Revision History Rev. Date Designed by Checked by

STRUCTURAL DESIGN REPORT -Steel bracings removal-

Fokker Logistics Park – Amsterdam, Netherlands

Revision History

Rev. Date Designed by Checked by Approved by Description

A 30.08.2017 EU MH MH First issue: DRAFT for review only

Responsible Dept.

Mat Bacon (MB)

Prepared by :

Emilian Ursu (EU)

Checked by:

Martin Hyde (MH)

Approved by: Martin Hyde (MH)

Date:

30.08.2017 Lang.

Eng. Format

A4 Pages

27

Document Title:

Strucutral design report –Steel bracings removal

Project:

Fokker Logistics Park, Amsterdam

Document Number

S.3114.00- A1– 001_A

Rev.

A

Project title : Fokker Logistics Park, Amsterdam

Project no: S.3114.00 Section: Calculation report

Date: 30.08.2017 Page 2

TABLE OF CONTENT

1. Introduction………………………….………………….…………………….…………....………..3 1.1 Project description.. ……… ………………………………………….……………………………....3

1.2 System of units..……………….……………… ………….. ………………….………..…………....5

1.3 General statements…………………….………………………………………….………………......5

2. Design norms…………………………………………………………..………..………….………….......5 2.1. Design norms.………………………...………………………….….…………….…….…………....5

2.2. Norms for materials………..…………………....………………………………….………………....6

3. Materials……………………………………………………………………….…………………...……....7

3.1. Structural steel and the steel connections………………………....…………. ………………………...7

3.2. Concrete and reinforcement steel…………………………..……. ….………………………………....7

3.3. Sustainability consideration….………………........…………. ………………………………………...8

4. Loads and loading combinations………………...…………………………………….…………...…….....8

4.1. Consequence class and supervision levels……...………………….……...………………………...…...8

4.2. Loading conditions. …………………………………………..……..……………...……………..….....9

4.3. Load combinations …………………………....…………….………………………………………....12

4.4. Validation for the loads assumptions……................…………. ……………………………………....14

4.5. Design constrains and limitations…….....................…………. ……………………………………....15

5. FEM model……….……………. ………………………………………………………………………...15

6. Structural design………………….………...…………………………………………………......……....19



Date: 30.08.2017 Page 3

1. Introduction

1.1. Project description

The purpose of this report is to summarise the main design parameters, principles and to present the supporting

report /calculations for the alteration works to the existing bracing system within an existing logistic building located

at Fokkerweg 3A, 1438 AN Oude Meer, Amsterdam, Netherlands.

Fig. 1. Site location and building configuration

The existing building has been designed as a warehouse and it was developed in two stages. The first stage

entailed the construction of a building with the overall dimensions of 178.60m (gridlines A to J ) x 83.75m (gridlines

1 to 8). The phase 1 construction was divided in two parts (called hereafter DC11 compartiment A and B) by a

separation joint located on gridlines E and F. Each compartiment was desined as an independend building with steel

bracings within the lateral walls and in the plan of the roof, in order to ensure the lateral stability. From the available

archive information, the foundations along gridline 8 were designed to accommodate a future extension which took

place in a later stage.

The phase 2 construction (gridlines A to J and 9 to 16) is a mirrored construction of Phase 1 building and

separated by a joint along gridlines 8 and 9. Similar to Phase 1 building, the second phase has been divided in two

parts (called hereafter DC12 compartiment C and D) by a separation joint along gridlines E and F (see figure 2 for

more details). The separation joint between both phases, along gridlines 8 and 9 has a width of 170mm and is filled by

a separation wall 150mm thick. The first 2.60m of the separation wall is made in pre-cast concrete and the remainder

up to the roof level is made of aerated concrete planks.

The project consists of the permanent removal of an existing bracing system made of flat steel plates

(15x120mm, grade S355) located on gridlines 8 and 9 and the replacement with two portal braces, in order to ensure

the free manouvering of an automated machince between the DC 11 compartiment B and DC 12 compartiment D (see

figures 3 and 4). On both grids, the bracings sytem is located between gridlines G and I. The total height of the

warehouse is about 13.65m and the roof is sloping towards gridlines G and I, where at the lowest point, the total height

is about 13.20m. The typical span between the grids is 21.68m.

Along the gridlines 8 and 9 and between the main grids, intermediate steel post have been provided in order

to support the roof construction. The steel post are IPE 400 and are placed at equal spaces of 5.42m. The edge posts,

in the corners of the compartiment are HEA200. In order to reduce the effective length of the steel posts, horizontal

rails made of box sections 80x80x4 were provided. These rails do not contribute to the bracing system of the building.

The top members wich supports the roof construction and spans between the vertical post are HEA 180.



Date: 30.08.2017 Page 4

Fig. 2. The existing warehouse and the main component part

Fig. 3. The existing warehouse and the main component parts

Separation

joint

Separation

joint

Separation

joint

Separation

joint

Steel

bracing

s

Ridge Eaves

Ridge Eaves

Ridge

Ridge Ridge



Date: 30.08.2017 Page 5

The geometry and the position of the 8 no. openings (2.0m wide and 12.20m high) is presented in the

following figure.

Fig. 4. The proposed openings within the existing separation concrete wall

1.2. System of units The metric system has been used throughout the entire project;

1.3.General statements This document has been developed based on the following design information:

Input from the client:

- Drawings in CAD format with the openings required for the automated machine: 8 no. openings

2.0m wide and 12.20m high;

- Design information in relation to the construction of the existing building: the steel frame, the base

plates and the anchor bolts, the ground floor construction and the foundation details;

Eurocode standards and the National Annexes for Netherlands;

Local specific regulations;

The structural system proposed for the alteration works is complying with the specific design criteria (lateral

deflections, the capacity of the existing foundation system) and the relevant site constraints. The final detailing / design

work and the construction programme will be discussed and agreed with the main contractor prior the tender issue

(Developed Design Stage): the erection sequences for the steel frame, lateral stability during construction, temporary

propping/ temporary bracings, the replace of the steel posts etc. The design work will be coordinated with the

construction programme.

Prior the tender issue (Developed Design Stage), the following aspects will be agreed with the client and the

main contractor:

The loads/loading scenarios during the construction sequence;

The design of the connections between the steel members: typical details;

The strategy for a safe erection on site and the water tightness during construction.

In terms of health and safety, a risk assessment for site specific hazards has been prepared separately by the

design team. The findings were disseminated to all the relevant parties and special measurement will be undertaken if

required.

2. Standards and regulations.

2.1. Design Norms. All the applicable in force regulations, laws and design norms for Netherlands whave been followed in the

design of all the alteration works. The national standards and design codes considered relevant and which have been

used, are listed below:

Basis of structural design:

- NEN EN 1990:2010– Eurocode - Basis of structural design;

NA to NEN EN 1990:2010 C2:2011 /NB:2011– Eurocode 0 - Basis of structural design – National Annex;

Action on structures:

- NEN EN 1991-1-1:2002, - Eurocode 1. Actions on structures. General actions. Densities, self-weight,

imposed loads for buildings



Date: 30.08.2017 Page 6

NA to NEN EN 1991-1-1:2002+C12011/NB:2011 - Eurocode 1. Actions on structures. General actions.

Densities, self-weight, imposed loads for buildings - National Annex.

- NEN EN 1991-1-3:2003- Eurocode 1. Actions on structures. General actions. Snow loads

NA to NEN DIN EN 1991-1-3:2003/NB:2013 Eurocode 1. Actions on structures. General actions. Snow

loads - National Annex.

- NEN EN 1991-1-4:2005 –Eurocode 1: Action on structures – Part 1-3: General action- Wind action;

NA to NEN EN 1991-1-4:2005 A1+C2/NB:2011–Eurocode 1: Action on structures – Part 1-3: General

action- Wind action-National Annex;

- NEN EN 1991-1-6:2005 Eurocode 1. Actions on structures. General actions. Actions during execution.

NA to NEN EN 1991-1-6:2005/NB:2013 Eurocode 1. Actions on structures. General actions. Actions

during execution - National Annex;

- NEN EN 1991-1-7:2006- Eurocode 1. Actions on structures. General actions. Accidental actions.

NA to NEN EN 1991-1-7:2006/NB:2011 Eurocode 1. Actions on structures. General actions. Accidental

actions - National Annex;

Design of concrete structures:

- NEN EN 1992-1-1:2005 Eurocode 2: Design of concrete structures. General rules and rules for buildings.

NA to NEN 1992-1-1:2005+C2:2011/NB:2016 Eurocode 2: Design of concrete structures. General rules

and rules for buildings - National Annex.

Design of steel structures:

- NEN EN 1993-1-1:2006 Eurocode 3. Design of steel structures. General rules and rules for buildings.

NA to NEN EN 1993-1-1:2006+C2:2011/NB:2011 Eurocode 3. Design of steel structures. General rules

and rules for buildings - National Annex.

- NEN EN 1993-1-5:2006 Eurocode 3. Design of steel structures. Plated structural elements.

NA to NEN EN 1993-1-5:2006 +C2:2011/NB:2011. Eurocode 3. Design of steel structures. Plated

structural elements - National Annex.

- NEN EN 1993-1-8:2006 Eurocode 3. Design of steel structures. Design of joints.

NA to NEN EN 1993-1-8:2006 +C2:2011/NB:2011. Eurocode 3. Design of steel structures. Design of

joints - National Annex

Geotechnical design:

- NEN EN 1997-1:2005 Eurocode 7. Geotechnical design. General rules.

- NA to NEN EN 1997-1:2006 A1+C1:2016/NB:2016 Eurocode 7. Geotechnical design. General rules -

National Annex.

2.2. Norms for materials. All the applicable in force regulations, laws and code of practice for Netherlands have been followed in the

design process in relation to the materials stipulated within the structural drawings and the technical specification. The

national standards and material norms considered relevant and which have been used are listed below:

- NEN EN 206:1 - Concrete - Part 1: Specification, performance, production and conformity and the National

Annex;

- NEN EN 13670, Execution of concrete structures and the National Annex;

- EN 197:1 - Cement - Part 1 : Composition, specifications and conformity criteria for common cements;

- NEN EN 10080 - Steel for the reinforcement of concrete: Weldable reinforcing steel;

- EN 10138 - Prestressing steels;

- NEN EN ISO 17660-1, Welding - Welding of reinforcing steel - Part 1: Load bearing welded joints and the

National Annex;

- NEN-EN 13055-1 Lichte toeslagmaterialen – Deel 1: Lichte toeslagmaterialen voor beton, mortel en

injectiemortel;

- NEN 3543 Nederlandse aanvulling op NEN-EN 13055-1;

- EN 10210-1:2006, Hot finished structural hollow sections of non-alloy and fine grain steels — Part 1:

Technical delivery conditions;

http://www.trada.co.uk/bookshop/view/B1F9519F-08F7-449E-AC8D-B31D05786062/NA_TO_BS_EN_1991112002_UK_National_Annex_to_Eurocode_1_Actions_on_structures_General_actions_Densities_selfweight_impos

http://www.trada.co.uk/bookshop/view/E551DF8C-A0C0-44D0-9387-D37DEA309832/NA_to_BS_EN_1991122002_UK_National_Annex_to_Eurocode_1_Actions_on_structures_General_actions_Actions_on_structures_exposed

http://www.trada.co.uk/bookshop/view/D03193AE-1FF1-4273-BEB2-DB2A5E1AEA3D/BS_EN_1991162005_Eurocode_1_Actions_on_structures_General_actions_Actions_during_execution

http://www.trada.co.uk/bookshop/view/0F720407-092C-490F-A7CB-A5DEDFBF7550/BS_EN_1991172006_Eurocode_1_Actions_on_structures_General_actions_Accidental_actions

http://www.trada.co.uk/bookshop/view/681C57EC-BF50-4E44-998A-128369F7AC2D/BS_EN_1992112004_Eurocode_2_Design_of_concrete_structures_General_rules_and_rules_for_buildings














Date: 30.08.2017 Page 7

- EN 10219-1:2006 Cold formed welded structural hollow sections of non-alloy and fine grain steels — Part

1: Technical delivery conditions;

- DIN EN 10025-5. Hot rolled products of structural steels. Technical delivery conditions for structural steels

with improved atmospheric corrosion resistance;

3. Materials

3.1. Structural steel and the steel connections All the structural steel used for rolled profiles, circular hollow sections, square/rectangular hollow sections,

equal/unequal angles, steel plates, gussets, stiffeners and end-plates will be S355 in accordance with NEN EN 1993-

1-1:2006 and NEN EN 10025-5. The structural steel S355 has the following properties, in accordance with NEN EN

10025-2:

nominal value of the yield strength: fy = 355 N/mm2;

tensile strength: fu = 510 N/mm2;

elongation at failure not less than 15%;

the ratio of the specified minimum ultimate tensile strength fu to the specified minimum yield strength fy

not less than 1.10.;

The partial safety coefficient applied to the material properties is γM,0= 1.0;

The high strength bolts used for all the bolted connection of the structural steel elements will be only from

the group of bolts 8.8 and 10.9., as they are defined in NEN EN 1993-1-8:2006:

group 8.8:

- yield limit of bolts: fyb = 640 N/mm2;

- resistance to fracture of the bolts: fub = 800 N/mm2;

group 10.9:

- yield limit of bolts: fyb = 900 N/mm2;

- resistance to fracture of the bolts: fub = 1000 N/mm2;

The anchor bolts/rods are used for the connections between the structural steel elements and the existing

foundation system. The anchor rods are obtained from round steel threaded subsequently. The washer and the nuts

used for the connection will be in accordance with provisions of the following standards: EN ISO 898-1:2002 and EN

14399-3:2005. All nuts and washers used in connections shall be galvanized.

The allowed diameters Ø for the anchor bolts are as follows: 20, 24, 30, 36, 42, 48, 56, and 64.

For connections with more than 2 anchor bolts, an embedded steel case will be provided in order to ensure the

stability and to maintain the design position of the anchor bolts when the concrete is poured. The embedded case will

be made up of steel S235. If the main contractor has a different proposal, this must be discussed with, agreed and

approved by the structural engineer prior the concrete pours.

In case of the connections of new steel members to existing concrete elements, chemical or mechanical anchors

will used instead. The chemical/ mechanical anchors specifications have been included within the structural drawings

and comprises the manufacturer, the anchor type, minimum embedment, mechanical properties and the installation

conditions.

The weld will be used for the connections of the structural steel elements and for the connections of the various

steel plates: end-plates, stiffeners and gussets. All welding consumables shall be in accordance with specified reference

standards in chapter 1.2.5 of NEN EN 1993-1-8:2006. For all the weld seams, it must be used electrodes with

mechanical characteristic higher than those corresponding to the steel types of the various combined steel

elements/plates.

The weld on site will be restricted as much as possible and limited to connections on the existing structures.

Site welding must be discussed with, agreed and approved by the structural engineer.

3.2. Concrete and reinforcement steel The use of concrete for this specific job is limited to replacements for local cuts within the existing foundations

of the main building (along gridlines 8 and 9, if required) and to foundations for the external strucutures. All the in-

situ concrete shall conform to the provisions of NEN EN 1992-1-1:2006 and EN 206:2002 Part 1.

The concrete used will have the following mechanical features /grade:

concrete grade: proposed C30/37;

- characteristic compressive cylinder strength of concrete at 28 days, fck =30 N/mm2;

- design value of concrete compressive strength, fcd =20 N/mm2;

- mean value of axial tensile strength of concrete, fctm=2.90 N/mm2;



Date: 30.08.2017 Page 8

exposure classes: XC2 / XA1 – the exposure class confirmed by the avaialbe documentation

XC4 /XC3- External concrete expoised / sheltered from rain;

maximum aggregate size: 20mm;

structural class: S4;

air entrainment: min. 3.5% and max.6%- optional and if concrete is poured during winter time;

All the reinforcement bars will be in accordance with EN 10080 and will have the following mechanical

properties:

reinforcing steel type: S500B;

characteristic yield strength: fyk=500N/mm2;

the concrete cover of the reinforcement bars for foundations: 50mm to all faces.

the concrete cover of the reinforcement bars for floor slabs: 25mm to all faces.

NOTE: the above values may chance based on the local conditions and will be specified in the structural drawings;

3.3. Sustainability considerations It is recommended that the regional suppliers to be located within maximum 100-150 kilometres of project

site, if feasible. As much as possible, the excavated soil can be reused for fillings and compacted layers, but only with

the prior approval of the structural engineer and in accordance with the recommendations of the available geotechnical

report. The concrete and the structural / reinforcing steel must be recycled and the local regulation must be consulted

in this repsect. The re-use of the existing materials must be discussed with, agreed and approved by the structural

engineer.

4. Loads and load combinations

4.1. Consequence class and supervision levels The consequence classes are defined in NEN EN 1990:2006 table B.1. According to this table the existing

building falls in CC2 category (wharehouse): Medium consequences for loss of human life, economic, social or

environmental consequences considerable. According to the design code, particular members of the structure may be

designated in the same, higher or lower consequences class than for the entire structure.

The Execution Class for the steel structure as a whole, was determined as follows:

a) Consequence Class – Table B1, NEN EN 1990:2006 :

CC2 - Medium consequence for loss of human life, or economic, social or environmental consequences

considerable.

b) Service Category – Table B.1, EN 1090-2:

SC1- Buildings and components designed for quasi static actions only;

c) Production Category – Table B.2, EN 1090-2:

PC2 - Welded components manufactured from steel grade products from S355 and above;

The Execution Class – Table B.3, EN 1090-2:

CC2 + SC1 + PC2 >>> EXC2

NOTE: The client or main contractor should appoint a steelwork sub-contractor with an Execution Class equal

to that required for the project, as determined by NEN EN 1090-2. It should be noted that steelwork contractors with

EXC3 capability can be used for EXC1, 2, & 3; and a steelwork contractor with EXC2 capability can only be used for

EXC1 & 2.Design supervision differentiation consists of various organisational quality control measures which can be

used together. For example, the definition of design supervision level may be used together with other measures such

as classification of designers and checking authorities.

In case of this project, the following design supervision levels will be achieved – in accordance with National

Annex of NEN EN 1990:2010, table NA.B1:

DSL 1 –Normal supervision: Checking by persons internal to the organization but different from those

originally responsible for the design.

DSL 3 –Supervision by the building inspectorate: Checking by the relevant authorities or a civil engineer

performing the inspection as an accredited entrepreneur on behalf of the authorities;



Date: 30.08.2017 Page 9

4.2. Loading conditions Based on the archive information made available by the client and judging on the overall configuration of the

internal speces, it is our understanding that the building has been designed mainly as a warehouse. The roof is made

of a lightweight construction (metal deck, insulation, vapor barier and hydroinsulation) and supported by steel trusses

that slopes towards the centre of the building in a jigsaw fahsion. The roof does not support any external equipment

and inside, it supports a light installation of sprinklers and lighting.

The floor of the building has been desined as a heavy duty floor, to support a total load of 50kN/m2; The floor

slab is supported by 219mm piles arranged on a grid 2.20m x2.20m; The internal columns are manily supported by

isolated pile caps, 2.0m x 0.60m with 2no. precast piles 320x320m. The edge columns within the gables and the

columns located along the separation joint and off main grids ( along gridlines 8 and 9) are supported by a concrete

ground beam 1.0m wide with pre-cast concrete piles located at an interval of about 2.70m;

Based on the available archive information and using a reverse engineering calculation we were able to assess

the following loading conditions for the roof of the building:

Dead load:

- self-weight of the steel trusses, including connections:0.20 kN/m2;

- self-weight of the roof construction: 0.80 kN/m2;

Permanent load:

- the hanging services and sprinkler installation:0.20 kN/m2;

Live load on the roof ( mainataince acess only):

- the live acess :0.60 kN/m2; - this values is in line with the provisions of the National Annex of NEN

EN 1991 -1-1:2002, table 6.10 – imposed loads on roofs.

According to table 6.10, for roof category H (not accessible) the load qk =1.0 kN/m2 is to be considered

uniformly distributed to an area of 10m2, for each individual structural member, with a rage of 0 for the

rest of the roof. Concervatively, a uniform distributed load of 0.60kN/m2 for the entire area of the roof

has been considered.

In addition to the loads listed above, the following loads have been consiederd in the structural design:

The snow load: according to NEN EN 1991-1-3:2003 - Eurocode 1. Actions on structures. General actions.

Snow load and the National Annex of Netherlands.

Location: Amsterdam, Netherlands;

According to the National Annex, for the Netherlands a minimum basic value must be adopted:

𝑺𝒌 = 𝟎. 𝟕𝟎 𝒌𝑵/𝒎𝟐

Also, there is no requirement for the exeptional snow loads on the ground, clause 4.3.(1);

According to the National Annex of NEN EN 1991-1-3:2006, in Netherlands, the following design situations

should be considered (table A.1, case A):

▪ persistent/transient design situation (no exceptional falls / no exceptional drifts):

- undrifted:

𝜇𝑖 · 𝐶𝑒 · 𝐶𝑡 · 𝑆𝑘 - drifted (Annex B is only informative in Netherlands):

𝜇𝑖 · 𝐶𝑒 · 𝐶𝑡 · 𝑆𝑘 μ1 - snow load shape coefficient:

μ1 = 0.80 (flat roof α ≈1⁰) Ce – exposure coefficient:

ce = 1.00 (conservatively, normal exposure) Ct – thermal coefficient of the roof:

ct = 1.00 ( thermal insulated roof) According to the national provisions, in case of multispan roofs, the drifted arrangement recommended in

NEN EN 1991-1-3:2006, clause 5.3.4.(3), do not apply. The same is valid in case of projections at the roof level

(parapets, separation walls ect.), clause 6.2.(2). On the other hand, the slope of the roof is about 1⁰ ( +13.565m at the

highest point, +13.218 at the lowest point and spans of 21.680m), therefore are no conditions to favorize the snow

drift.

Therfore, within the persistent/transient design situation (no exceptional falls / no exceptional drifts), the snow

load at roof level has the following value:

𝑺 = 𝟎. 𝟓𝟔 𝒌𝑵/𝒎𝟐

Since the maximum value of the live load on the roof can’t act simultaneously with the maximum snow load

( full access on the roof with maximum snow load), the higher value of the loads will be considered.

dkd

Tekstvak

Snow and live load don't have to be combined with wind load, see my comments on paragraph 4.3. So in this case they are not relevant.



Date: 30.08.2017 Page 10

The wind load: according to NEN EN 1991-1-4:2005 –Eurocode 1: Action on structures – Part 1-3: General

action- Wind action and the National Annex of Netherlands.

According to the National Annex of NEN EN 1991-1-4:2005, the fundamental value of the basic wind velocity

vb,0 , for sites located within Zone II, is given in Table NB.1:

vb,0 = 27.00 m/s

qb,0 = 0.456 kN/m2

Fig. 5. Wind zone map for the territory of Netherlands

The basic wind velocity can be calculated from the following expression:

𝑣𝑏 = 𝐶𝑠𝑒𝑎𝑠𝑜𝑛 · 𝐶𝑑𝑖𝑟 · 𝐶𝑝𝑟𝑜𝑏 · 𝑣𝑏,0

Cseason – represents the season coefficient and the recommended value is 1.00;

Cdir– represents the directional factor and the recommended value is 1.00;

Cprob – represents the probabilistic factor and it is determined as follows:

𝐶𝑝𝑟𝑜𝑏 = [1 − 𝐾 · 𝑙𝑛(−𝑙𝑛(1 − 𝑝))

1 − 𝐾 · 𝑙𝑛(−𝑙𝑛0.98)]

𝑛

K – represents the shape parameter depending on the coefficient of variation of the extreme-value

distribution; the recommended value is K = 0.235 (table NB.2);

n – represents the exponent; the recommended value is n = 0.5;

𝐶𝑝𝑟𝑜𝑏 = [1 − 0.235 · 𝑙𝑛(−𝑙𝑛(1 − 0.02))

1 − 0.235 · 𝑙𝑛(−𝑙𝑛0.98)]

0.5

= 1.00

𝑣𝑏 = 𝐶𝑠𝑒𝑎𝑠𝑜𝑛 · 𝐶𝑑𝑖𝑟 · 𝐶𝑝𝑟𝑜𝑏 · 𝑣𝑏,0 = 27.00 𝑚/𝑠

𝒗𝒃 = 𝟐𝟕. 𝟎𝟎 𝒎/𝒔

According to the National Annex of Netherlands, table NB.5, for sites located within Zone II and surrounded

by open land, without constructions or uncultivated, the value of peak velocity pressure qp(z) at height z, which includes

mean and short-term velocity fluctuations, has the following value:

for z =15 m: 𝑣𝑝(𝑧 = 10𝑚) = 0.850 𝑘𝑃𝑎

for z =15 m: 𝑣𝑝(𝑧 = 15𝑚) = 0.980 𝑘𝑃𝑎

The site of the

building

dkd

Toelichting

This is water.

dkd

Toelichting

The actual project location is at this position.



Date: 30.08.2017 Page 11

The maximum height of the warehouse at the ridge is about 13.565m, therefore, by using linear interpolation

between the above values, the value of peak velocity pressure qp(z) is:

𝒒𝒑(𝒛 = 𝟏𝟑. 𝟓𝟔𝟓) = 𝟎. 𝟗𝟐𝟏 𝐤𝐏𝐚;

The wahrehouse is made of four independent units: DC 11 compartiment A and B and DC 12 compartiment

C and D. The overall dimensions of the wharehouse are 167.00m x 178.60m. The overall dimensions of one unit are

83.50m x 89.30m. Each unit has a braced frame on the perimeter gridlines, therefore two braced frames for each wind

direction. The overall height of the building is 13.565m.

According to the National Annex of NEN EN 1991-1-4:2005, table NB.6, for buildings with h/d <1.0, the

pressure coefficients are as follows:

lateral wall subject directely to wind pressure (zone D): cpe = +0.800;

we,1 = 0.80· 0.921 = 0.736 kPa

lateral wall in suction (the wall opposite to the wall subject to wind pressure): cpe = -0.500;

we,2 = -0.50· 0.921 = 0.460 kPa

Fig. 6. Wind pressure/suction on the building envelope

Conservatively, since the sutructre is not sensitive to wind vibrations, the dynamic reposne coefficient cscd=1.00.

The total lateral forces produced by the wind dynamic action have the following values:

lateral wall subject to wind pressure (zone D);

Fw,1 = cscd·we,1 ·Awall =1.00· 0.80· 0.921 = 834.6 kN

lateral wall subject to wind sunction (zone E);

Fw,2 = cscd·we,2 ·Awall =1.00· -0.50 · 0.921 = 521.6 kN

friction along the roof surface (enhancedrough surface cfr=0.03);

Ffr = cfr·qp (z)·4h·b=0.03·0.921·4·13.565·83.50= 125.2 kN

Pressure Suction

Suction Pressure

Steel

bracing

s

Steel

bracing

s



Date: 30.08.2017 Page 12

The total wind load in each scenario (pressure /suction) will be devided between two braced bays, as follows:

lateral wall subject to wind pressure (zone D);

Fwt,1 = (Fw,1 + Ffr) / 2 = (834.6+125.2) / 2 = 480 kN

lateral wall subject to wind suction (zone E);

Fwt,1 = (Fw,1 + Ffr) / 2 = (521.6+125.2) / 2 = 324 kN

Further, the load cases considered relevant for the structural desing have been detail in table 1, as follows:

Table 1. The load cases considered within the structural analysis

4.3. Load combinations The load combinations of all the previous action have been considered, in accordance with NEN

EN1990:2010– Eurocode - Basis of structural design.

a) Ultimate limit state (ULS):

The following ultimate limit states shall be verified as relevant:

EQU : Loss of static equilibrium of the structure or any part of it considered as a rigid body;

STR : Internal failure or excessive deformation of the structure or structural mem members, including

footings, piles, basement walls, etc., where the strength of construction materials of the structure

governs;

GEO : Failure or excessive deformation of the ground where the strengths of soil or rock are

significant in providing resistance;

FAT : Fatigue failure of the structure or structural members;

The combinations of actions for ULS have the following format:

persistent or transient design situations (fundamental combinations):

∑ 𝛾𝐺,𝑗 ·

𝑗≥1

𝐺𝑘,𝑗 + 𝛾𝑝 · 𝑃 + 𝛾𝑄,1 · 𝑄𝑘,1 + ∑ 𝛾𝑄,𝑖 ·

𝑖>1

𝜓0,𝑖 · 𝑄𝑘,𝑖

where:

P - relevant representative value of a prestressing action (if applicable);

γP - partial factor for prestressing actions;

Gk,j - characteristic value of permanent action j;

γG,j - partial factor for permanent action j;

Qk,1 - characteristic value of the leading variable action 1;

Qk,i - characteristic value of the accompanying variable action i;

γQ,i - partial factor for variable action i;

ψ0 - factor for combination value of a variable action;

accidental design situations:

∑ 𝐺𝑘,𝑗

𝑗≥1

+ 𝑃 + 𝐴𝑑 + (𝜓1,1 𝑜𝑟 𝜓2,1) · 𝑄𝑘,1 + ∑ 𝜓2,𝑖 · 𝑄𝑘,𝑖

𝑖>1

where:

P - relevant representative value of a prestressing action (if applicable);

γP - partial factor for prestressing actions;

Gk,j - characteristic value of permanent action j;

γG,j - partial factor for permanent action j;

Ad - design value of an accidental action;

No. Load case Designation

1 Self-weight DL1 2 Permanent load PL

3 Live load LL1

4 Wind Load - Pressure WXP

5 Wind Load - Suction WXN

dkd

Toelichting

Divided by two because half of the wind loads is transfered to the foundation by the columns in the facade.

dkd

Pijl

dkd

Ovaal

dkd

Toelichting

For the calculation of the braces / portal frames wind pressure and suction must be combined. They are one load case. Furthermore the windloads may be reduced with a factor of 0,85 due to the lack of correlation, this according to article 7.2.2(3).



Date: 30.08.2017 Page 13

Qk,1 - characteristic value of the leading variable action 1;

Qk,i - characteristic value of the accompanying variable action i;

γQ,i - partial factor for variable action i;

ψ1 - Factor for frequent value of a variable action;

ψ2 - Factor for quasi-permanent value of a variable action;

b) Serviceability limit state (SLS):

The combinations of actions to be taken into account in the relevant design situations should be appropriate

for the serviceability requirements and performance criteria being verified. The combinations of actions for

serviceability limit states are defined symbolically by the following expression:

characteristic combination (normally used for irreversible limit states):

∑ 𝐺𝑘,𝑗

𝑗≥1

+ 𝑃 + 𝑄𝑘,1 + ∑ 𝜓0,𝑖 · 𝑄𝑘,𝑖

𝑖>1

frequent combination:

∑ 𝐺𝑘,𝑗

𝑗≥1

+ 𝑃 + 𝜓1,1 · 𝑄𝑘,1 + ∑ 𝜓2,𝑖 · 𝑄𝑘,𝑖

𝑖>1

quasi-permanent combination:

∑ 𝐺𝑘,𝑗

𝑗≥1

+ 𝑃 + ∑ 𝜓2,𝑖 · 𝑄𝑘,𝑖

𝑖≥1

According to NEN EN 1990:2010, the effects of actions that cannot exist simultaneously due to physical or

functional reasons should not be considered together in combinations of actions.

Table 2. Values of ψ factors for buildings

Action ψ0 ψ1 ψ2

Imposed loads in buildings (for categories see EN 1991-1-1)a

— Category A: Domestic, residential areas 0.7 0.5 0.3

— Category B: Office areas 0.7 0.5 0.3

— Category C: Congregation areas 0.7 0.7 0.6

— Category D: Shopping areas 0.7 0.7 0.6

— Category E: Storage areas 1.0 0.9 0.8

— Category F: Traffic areas, vehicle weight ≤ 30 kN 0.7 0.7 0.6

— Category G: Traffic areas, 30 kN ≤ vehicle weight ≤ 160 kN 0.7 0.5 0.3

— Category H: Roofs 0.7 0 0

For snow and ice loads, see NEN EN 1991-1-3

— Sites located at altitudes of up to 1 000 m above sea level 0.5 0.2 0.0

— Sites located at altitudes of more than 1 000 m above sea level N/A N/A N/A

For wind loads, see NEN EN 1991-1-4 0.7 0.2 0.0

For thermal actions (non-fire), see NEN EN 1991-1-5 0.6 0.5 0.0

For the settlements of foundations, see NEN EN 1997 1.0 1.0 1.0

Other actionsb, c 0.8 0.7 0.5

a) For reduction factors to be applied to imposed loads in multi-storey buildings, see NEN EN 1991-1-1.

b) Hydraulic pressure is generally to be treated as a variable action for which the ψ factors need to be specified as a function of the

given location. Hydraulic pressure whose magnitude is limited by geometrical conditions may be treated as a permanent action

for which all ψ factors shall be set equal to 1,0.

c) The ψ factors for machine loads shall be specified as required by the operational conditions.

The load combination considered for the structural desing are as follows:

dkd

Doorhalen

dkd

Doorhalen

dkd

Doorhalen

dkd

Typemachine

0,0

dkd

Typemachine

0,0

dkd

Toelichting

The factors are not the factors according to the dutch annex. I adjusted them for category H, snow and wind.

dkd

Typemachine

0,0



Date: 30.08.2017 Page 14

a) Ultimate limit state (ULS): - ULS 1 : 1.35·DL + 1.35·PL +1.50·LL + 1.05 WXP

- ULS 2 : 1.35·DL + 1.35·PL +1.05·LL + 1.50 WXP

- ULS 3 : 0.90·DL + 0.90·PL + 1.50 WXP

- ULS 4 : 1.35·DL + 1.35·PL +1.50·LL + 1.05 WXN

- ULS 5 : 1.35·DL + 1.35·PL +1.05·LL + 1.50 WXN

- ULS 6 : 0.90·DL + 0.90·PL + 1.50 WXN

b) Serviceablity limit state (SLS): - SLS 1 : 1.00·DL + 1.00·PL +1.00·LL + 0.60 WXP

- SLS 2 : 1.00·DL + 1.00·PL +0.70·LL + 1.00 WXP

- SLS 3 : 0.90·DL + 0.90·PL + 1.00 WXP

- SLS 4 : 1.00·DL + 1.00·PL +1.00·LL + 0.60 WXN

- SLS 5 : 1.00·DL + 1.00·PL +0.70·LL + 1.00WXN

- SLS 6 : 0.90·DL + 0.90·PL + 1.00 WXN.

4.4. Validation for the loads assumptions In order to check the veracity of the initial assessment for the loading conditions for the existing warehouse, a

reverse engineering calculation has been performed. For the purpose of this check, one of the central columns of the

wahrehouse has been considered. The central columns are made of box sections 300x5 (S355) and the maximum

height is 13.565m.

All the central columns support steel trusses and the afferent loaded area has the following value:

Aaf = 21.860 x 11.96m =259.29 m2

The forces on top of the steel column due to the roof structure and the assosciated loads,are as follows :

- self-weight of the roof structure:

1.0 kN/m2 · 259.29 m2 = 259.29 kN

- permanent load (hanging services):

0.20 kN/m2 · 259.29 m2 = 51.85 kN

- live load (access on the roof):

0.60 kN/m2 · 259.29 m2 = 155.57 kN

Considering the load combinations described at chapter 4.3, the capacity of the steel column has been checked

as decribed below .

Governing Load Case: 6 ULS1: 1.35*DL+1.35*PL+1.50*LL+1.05WL (2+1)*1.35+3*1.50+4*1.05

SECTION PARAMETERS: 300x5

h=300 mm γM0 =1.00 γM1=1.00

b=300 mm Ay=3000 mm2 Az=2900 mm2 Ax =5900 mm2

tw=5 mm Iy=85599167 mm4 Iz=85599167 mm4 Ix =128361875 mm4

tf=5 mm Wely=570661 mm3 Welz=570661 mm3 Aeff =3911 mm2

INTERNAL FORCES AND CAPACITIES: NEd = 661.57 kN

Nc,Rd = 2094.50 kN

Nb,Rd = 668.95 kN Class of section = 3

BUCKLING PARAMETERS:

About y axis: About z axis: Ly = 13.33 m λ_y = 1.19 Lz = 13.33 m λ_z = 1.19

Lcr,y = 13.33 m Xy = 0.48 Lcr,z = 13.33 m Xz = 0.48

λy = 110.64 λz = 110.64

Torsional buckling: Flexural-torsional buckling Curve,T=b αT=0.34 Curve,TF=b αTF=0.34

Lt =13.33 m ØT=0.48 Ncr,y=975.12 kN ØTF=0.48

Ncr,T =348794.03 kN XT=1.00 Ncr,TF=348794.03 kN XTF=1.00

λ_T=1.19 Nb,T,Rd = 1388.50 kN λ_TF=0.06 Nb,TF,Rd=1388.50 kN

dkd

Tekstvak

I would advise to make the following load combinations: ULS: 1.2 DL + 1,2 PL + 1,5 WX SLS: 1,0 DL + 1,0 PL + 1,5 WX The following load case does not lead to a normative cobintion because ψ0 = 0 and can thus be omitted. 1.35 DL + 1,35 PL + 1,5 ψ0 WX



Date: 30.08.2017 Page 15

VERIFICATION FORMULAS: Section strength check: NEd /Nc,Rd = 0.32 < 1.00 (6.2.4.(1))

Global stability check of member: λy= 110.64 < λmax = 120 λz = 110.64 < λmax = 210.00 STABLE

NEd /Min(Nb,Rd ; Nb,T,Rd ; Nb,TF,Rd) = 0.99 < 1.00 (6.3.1) >> Section OK

Based on the reverse engineering calculation, the central column is able to withstand the loads assumend in

the initial assessement with an utilisation ratio of 0.99. Therefore, the loads assumed are conservative and will not

exceed the estimated values.

4.5. Design constraints and limitations The structural desing has been governed by the following design constraints:

the maximum lateral deflection under SLS combinations (storey drift): L/300 ≈ 45mm;

the maximum forces developed within the existing members will not exceed the current capacity: steel

member and the assosciated connections;

The overall approach regarding the replacement of the existing steel bracings was to introduce two new portal

frames within the existing braced bays and the associated sizes have been tuned to reproduce the same lateral

displacements as the initial system. All the bases of the steel portals have been condiered as pinned and no bending

moment will be transferred to the foundation system. Therefore, the foundation system will not require additional

enhancement to accommodate the new lateral resisting system.

5. FEM model The structural analysis of both, the existing bracings system and the proposed portal frames, have been carried

out using the software Robot Structural Analysis 2016. In this respect, a 3D FEM model has been elaborated by

modelling the steel frames along the gridlines 8 and 9,including the flat steel bracings, the steel posts and the horizontal

rails. Each element has been considered with the relevant geometric configuration, section size or thickness and

appropriate boundary conditions (supports, releases etc.)

The purpose of the structural analysis was as follows:

the determination of stress level in various members;

the design of the structural members based on the above level of stress;

the determination of deflections and lateral displacements;

to assess the overall behaviour of the proposed system and the lateral stability.

Fig. 7.The 3D FEM model of the existing steel frame

The horizontal rails have been included in the model to reduce the effective length of the steel posts, but

without any contribution to the lateral stability of the frame. Also, the flat steel plates, 15 x120mm has been modelled

to withstand only tension forces. All the bases of the steel posts IPE 400 have been considered fixed on the strong axis

(perpendicular to the steel frame) and pinned on the weak axis (along the steel frame).

Existing flat

steel bracings

Existing flat

steel bracings

Door frame/Roller

shutter

Door frame/Roller

shutter Steel posts

IPE400

Horizontal

rails 80x80x5



Date: 14.06.2017 Page 16

Fig. 8.The 3D FEM model of the proposed portal frames

Fig. 9.The section sizes for the steel members of the portal frame.

In case of each scenario (existing steel bracings or portal frames), the assosciated loads have been

calculated based on the affrent areas and the loading conditions assessed at chapter 4.2.

NOTE: In order to simplify the calculations and to have a better control of the 3D model, the self-weight of

the roof construction has been included in the permement load case. In all the combinations, the self-weight

and the permanent loads have the same coefficient and therefore the results will not be affected. On the other

hand, the dead load case will contain only the self-weight of the steel memembers calculated automatically

by the software.

a) Loads on the top edge beams HEA 180

The metal deck of the roof construction spans between the secondary steel truss and the edge beam.

The value of the bay is about 6.0m, therefore the edge beams will support half of the loads:

- permement load: 1.20kN/m2 (1.0 kN/m2 from self weight and 0.20 kN/m2 from hanging services):

Linear load = 1.20kN/m2 · 6.0m/2 = 3.60 kN/m

- live load: 0.60 kN/m2;

Linear load = 0.60 kN/m2 · 6.0m/2 = 1.80 kN/m

b) Loads on the edge posts IPE 400 which support steel trusses

The reaction on each end of the main steel trusses are as follows:

- permement load: 1.20kN/m2 (1.0 kN/m2 from self weight and 0.20 kN/m2 from hanging services):

Point load = 1.20kN/m2 · ( 21.68m x 5.98m)/2 = 77.8 kN

Concentrated moment = Point load · Ecc = 77.8·0.20 = 15.60 kNm

The proposed

portal frames New steel post

around the openings

New column –welded

plates section

Horizontal

rails 80x80x5

Haunch

Haunch

New beam –welded

plates section

Central column: IPE400+

2no. 1200x400 flanges

30mm, web 20mm

Edge column: IPE400+

1200x400, flanges

30mm, web 20mm

Steel beam: 1300x400,

flanges 30mm, web 20mm

Haunches 400x300x16



Date: 30.08.2017 Page 17

- live load: 0.60 kN/m2;

Point load = 0.60 kN/m2 · ( 21.68m x 5.98m)/2 = 38.90 kN

Concentrated moment = Point load · Ecc = 38.90·0.20 = 7.78 kNm

c) Wind loads:

- lateral wall subject to wind pressure:

Fedge = Fwt,1 / 4 = 480 / 4 = 120 kN

Fcentral = Fwt,1 / 2 = 480 / 2 = 240 kN

- lateral wall subject to wind pressure:

Fedge = Fwt,2/ 4 = 480 / 4 = 81 kN

Fcentral = Fwt,2 / 2 = 480 / 2 = 162 kN

Fig.10. The braced frame with the permanent loads

Fig.11. The braced frame with the live loads

Fig.12. The braced frame with the wind loads

dkd

Ovaal

dkd

Toelichting

Copy / paste

dkd

Toelichting

See also previous comments



Date: 30.08.2017 Page 18

Fig.13. The portal frame with the permanent loads

Fig.14. The portal frame with the live loads

Fig.14. The portal frame with the wind loads

NOTE: The bending moments considered on the perpendicular plan of the frame are due to the eccentricity

of the truss connection in repect to the centre line of the IPE 400 posts. These eccentricietes introduce

bending moments and the effect of these will be review in order to ensure a safe removal of the concrete

wall between the DC11 compartiment B and DC 12 compartiment D. In other words, it will be checked if

the concrete wall had a stabilisation role for the flange of the steel posts IPE400.



Date: 30.08.2017 Page 19

6. Structural analysis Following on from the completion of the 3D modelling of the steel frames and the assignment of the

associated loads, both FEM models have been run independently. In first instance, the existing steel frame

has been cheked on the following aspects:

maximum lateral displacement:

δbraced,frame = 27mm < L/300 = 45mm OK

Fig.15. The maximum lateral displacement for the steel frame with flat plates bracings

maximum tension force within the steel brace, 15x120mm (S355) :

Ntension,max = 450 kN

Fig.16. The maximum tension force within the flat plates bracings

a) The tension capacity of the flat steel plate, 15x120mm (S355):

NT,Rd = Aplate· fyd = 15· 120· 355 / 103 = 639 kN

Ntension,max = 450 kN < NT,Rd = 639 kN Bracing safe in tension;

b) The capacity of the steel connection (3 no bolts M24 gr.8 8):

b.1) The shear capacity of the connection:

𝐹𝑉,𝑅𝑑 =𝛼𝑣 · 𝑓𝑢𝑏 · 𝐴

𝛾𝑀2=

0.60 · 800 ·𝜋 · (0.89 · 24)2

41.25

= 137.60 𝑘𝐾/𝑏𝑜𝑙𝑡

fub = 800 N/mm2 – bolts group 8.8;

αv= 0.60 – bolts group 8.8;

A- the area of the bolt in the threaded zone;

γM2=1.25 - partial safety coefficient ;

The shear apacity of the connection has the following value:

FRd, shear = 3 Fv,Rd = 412.80 kN

Ntension,max = 450 kN > FRd, shear = 412.80 kN Bracing not safe;

b.2) The capacity to pressure on the bolts holes:

𝐹𝑏,𝑅𝑑 =𝑘1 · 𝑎𝑏 · 𝑓𝑢 · 𝑑 · 𝑡

𝛾𝑀2

- edge bolts:

𝛼𝑑 =𝑒1

3𝑑0=

55

3 · 26= 0.705



Date: 30.08.2017 Page 20

- central bolts:

𝛼𝑑 =𝑝1

3𝑑0−

1

4=

80

3 · 26−

1

4= 0.776

𝑎𝑏 = 𝑚𝑖𝑛 (𝛼𝑑; 𝑓𝑢𝑏

𝑓𝑢; 1.0)

𝑓𝑢𝑏

𝑓𝑢=

800

510= 1.568

- edge bolts:


𝑓𝑢; 1.0) = 𝑚𝑖𝑛(0.705; 1.568 ; 1.0) = 0.705

- central bolts:


𝑓𝑢; 1.0) = 𝑚𝑖𝑛(0.776; 1.568 ; 1.0) = 0.776

𝑘1 = 𝑚𝑖𝑛 (2.80𝑒2

𝑑0− 1.70; 2.50) = 𝑚𝑖𝑛 (2.80

60

26− 1.70; 2.50) = 2.50

- the capacity for the edge bolt:

𝐹𝑏,𝑅𝑑,𝑒𝑑𝑔𝑒 =𝑘1 · 𝑎𝑏 · 𝑓𝑢 · 𝑑 · 𝑡

𝛾𝑀2=

2.5 · 0.705 · 510 · 15 · 24

1.25= 258.9 𝑘𝑁

- the capacity for the central bolts:

𝐹𝑏,𝑅𝑑,𝑐𝑒𝑛𝑡𝑟𝑎𝑙 =𝑘1 · 𝑎𝑏 · 𝑓𝑢 · 𝑑 · 𝑡

𝛾𝑀2=

2.5 · 0.776 · 510 · 15 · 24

1.25= 285 𝑘𝑁

The capacityof the connection to pressure on the bolts holes is: Fb,Rd = 3·min(Fb,Rd, central ; Fb,Rd, edge) = 775 kN

Ntension,max = 450 kN < Fb,Rd = 775 kN Connection safe for pressure on bolts holes;

b.3) The capacity to connection for block shear:

𝑉𝑒𝑓𝑓,1,𝑅𝑑 =𝑓𝑢 · 𝐴𝑛𝑡

𝛾𝑀2+

𝑓𝑦

√3· 𝐴𝑣

𝛾𝑀0

Ant - the area of the steel subject to tension;

Ant = 60 · 15 = 900 mm2;

Av - the area of the steel subject to shear;

Av = (50+80+80) · 15 = 3225 mm2;

𝑉𝑒𝑓𝑓,1,𝑅𝑑 =𝑓𝑢 · 𝐴𝑛𝑡

𝛾𝑀2+

𝑓𝑦

√3· 𝐴𝑣

𝛾𝑀0=

510 · 900

1.25+

355

√3· 3225

1.0= 1028 𝑘𝑁

Ntension,max = 450 kN < Veff,1,Rd = 1028 kN Connection safe for pressure on bolts holes;

The following conclusions can be drawn based on the previous calculations:

- the capacity of the bracing is dictated by the shear resistance of the connection:

Bracing tension capacity = 412.80 kN

- the wind loads assumed in the strucutural analysis are slightly overestimated on the safe side. For

the purpose of these calculations, the forces will remain as assessed initially.

In order to ensure a safe removal of the concrete wall between the DC11 and DC 12 compartiments,

the stability of the steel posts IPE 400 has been checked. In these calculations it has been assumed that the

effective length on the strong axis (perpendicular to the steel frame plan) is equal with the physical length

of the column and on the weak direction, the effective length is reduced due to the horizontal rails, which

will act as a lateral restraint.

Therefore, the effective length for the existing steel posts are as follows:

- strong axis : Ly= Lcolumn = 13.565m;

- weak axis: Lz= 0.35·Lcolumn = 4.75m;



Date: 30.08.2017 Page 21

Fig.17. The maximum axial force on the steel posts IPE 400


SECTION PARAMETERS: IPE 400 h=400 mm gM0=1.00 gM1=1.00

b=180 mm Ay=5603 mm2 Az=4273 mm2 Ax=8450 mm2

tw =9 mm Iy=231300000 mm4 Iz=13180000 mm4 Ix=513000 mm4

tf =14 mm Wply=1307000 mm3 Wplz=229000 mm3

----------------------------------------------------------------------------------------------------------------------------------------

INTERNAL FORCES AND CAPACITIES: N,Ed = 429.37 kN My,Ed = -1.82 kN*m Mz,Ed = 0.01 kN*m Vy,Ed = 0.04 kN

Nc,Rd = 2999.75 kN My,Ed,max = -29.22 kN*m Mz,Ed,max = 0.78 kN*m

Vy,c,Rd = 1148.47 kN

Nb,Rd = 930.99 kN My,c,Rd = 463.99 kN*m Mz,c,Rd = 81.30 kN*m Vz,Ed = -3.23 kN

MN,y,Rd = 463.99 kN*m MN,z,Rd = 81.30 kN*m Vz,c,Rd = 875.81 kN

Mb,Rd = 91.88 kN*m Class of section = 1

----------------------------------------------------------------------------------------------------------------------------------------

LATERAL BUCKLING PARAMETERS: z = 0.00 Mcr = 91.88 kN*m Curve,LT - c XLT = 0.20

Lcr,low=13.57 m Lam_LT = 2.25 fi,LT = 2.85 XLT,mod = 0.20

----------------------------------------------------------------------------------------------------------------------------- -----------


About y axis: About z axis: Ly = 13.57 m Lam_y = 1.09 Lz = 13.57 m Lam_z = 1.59

Lcr,y = 13.57 m Xy = 0.61 Lcr,z = 4.75 m Xz = 0.31

Lamy = 81.99 kyy = 1.78 Lamz = 120.21 kyz = 2.30

Torsional buckling: Flexural-torsional buckling Curve,T=b alfa,T=0.34 Curve,TF=b alfa,TF=0.34

Lt=13.57 m fi,T=1.65 Ncr,y=2543.25 kN fi,TF=1.65

Ncr,T=1585.07 kN X,T=0.39 Ncr,TF=1585.07 kN X,TF=0.39

Lam_T=1.09 Nb,T,Rd=1176.32 kN Lam_TF=1.38 Nb,TF,Rd=1176.32 kN

------------------------------------------------------------------------------------- ---------------------------------------------------

VERIFICATION FORMULAS: Section strength check: N,Ed/Nc,Rd = 0.14 < 1.00 (6.2.4.(1))

(My,Ed/MN,y,Rd)^ 2.00 + (Mz,Ed/MN,z,Rd)^1.00 = 0.00 < 1.00 (6.2.9.1.(6))

Vy,Ed/Vy,c,Rd = 0.00 < 1.00 (6.2.6.(1))

Vz,Ed/Vz,c,Rd = 0.00 < 1.00 (6.2.6.(1))

Global stability check of member: Lambda,y = 81.99 < Lambda,max = 120 Lambda,z = 120 < Lambda,max = 120 STABLE

N,Ed/Min(Nb,Rd,Nb,T,Rd,Nb,TF,Rd) = 0.46 < 1.00 (6.3.1)



Date: 30.08.2017 Page 22

My,Ed,max /Mb,Rd = 0.32 < 1.00 (6.3.2.1.(1))

N,Ed/(Xy*N,Rk/gM1)+kyy*My,Ed,max/(XLT*My,Rk/gM1)+ kyz*Mz,Ed,max/(Mz,Rk/gM1) = 0.82 < 1.00 (6.3.3.(4))

N,Ed/(Xz*N,Rk/gM1)+kzy*My,Ed,max/(XLT*My,Rk/gM1)+ kzz*Mz,Ed,max/(Mz,Rk/gM1) = 0.79 < 1.00 (6.3.3.(4))

The steel posts IPE 400 are safe if the concrete wall is removed ;

As a cursory check, the capacity of the top edge beam H180 has been reviewed, as follows:


SECTION PARAMETERS: HEA 180 h=171 mm gM0=1.00 gM1=1.00


tw=6 mm Iy=25100000 mm4 Iz=9250000 mm4 Ix=149000 mm4

tf=10 mm Wply=325000 mm3 Wplz=156000 mm3

---------------------------------------------------------------------------------------- ------------------------------------------------

INTERNAL FORCES AND CAPACITIES: N,Ed = 175.28 kN My,Ed = 26.52 kN*m

Nc,Rd = 1608.15 kN My,Ed,max = 26.52 kN*m

Nb,Rd = 462.14 kN My,c,Rd = 115.38 kN*m

MN,y,Rd = 115.38 kN*m

Mb,Rd = 82.30 kN*m Tt,Ed = 0.00 kN*m

Class of section = 2

----------------------------------------------------------------------------------------------------------------------------- -----------

LATERAL BUCKLING PARAMETERS: z = 0.00 Mcr = 113.42 kN*m Curve,LT - b XLT = 0.69

Lcr,upp=5.42 m Lam_LT = 1.01 fi,LT = 0.98 XLT,mod = 0.71

----------------------------------------------------------------------------------------------------------------------------- -----------



Lcr,y = 5.42 m Xy = 0.62 Lcr,z = 5.42 m Xz = 0.29

Lamy = 72.82 kyy = 1.37 Lamz = 119.96 kzy = 0.71

Torsional buckling: Flexural-torsional buckling Curve,T=c alfa,T=0.49 Curve,TF=c alfa,TF=0.49




----------------------------------------------------------------------------------------------------------------------------- -----------


My,Ed/My,c,Rd = 0.23 < 1.00 (6.2.5.(1))

My,Ed/MN,y,Rd = 0.23 < 1.00 (6.2.9.1.(2))

Tau,ty,Ed/(fy/(sqrt(3)*gM0)) = 0.00 < 1.00 (6.2.6)

Tau,tz,Ed/(fy/(sqrt(3)*gM0)) = 0.00 < 1.00 (6.2.6)

Global stability check of member: Lambda,y = 72.82 < Lambda,max = 150 Lambda,z = 119.96 < Lambda,max = 150 STABLE


My,Ed,max/Mb,Rd = 0.32 < 1.00 (6.3.2.1.(1))

N,Ed/(Xy*N,Rk/gM1) + kyy*My,Ed,max/(XLT*My,Rk/gM1) = 0.62 < 1.00 (6.3.3.(4))

N,Ed/(Xz*N,Rk/gM1) + kzy*My,Ed,max/(XLT*My,Rk/gM1) = 0.61 < 1.00 (6.3.3.(4))

The top steel beams HEA180 are safe if the concrete wall is removed ;

Following on from the complete review of the existing steel frame in the current conditions, the

analysis focused on the proposed portal frames. The flat steel bracings have been removed entirely

and replaced by a portal frame, one on each gridline. The section sizes of the steel portals have been



Date: 30.08.2017 Page 23

increased iteratively until the lateral displacement matched the displacements of the frame with flat

steel bracings. In order to reduce the steel consumption and to suit the 8 no. openings requested by

the client, additional haunches have been included. Also, where the new proposed openings clahsed

with the existing IPE 400 posts, the posts in question were removed and replaced with two stel

members UB 406x178x67 (S355) on each side of the opening.

In the structural analysis of the new lateral resisting system, the following items were checked:

maximum lateral displacement:

δportal,frame = 30mm < L/300 = 45mm OK

δportal,frame = 30mm ≈δbraced,frame = 27mm OK

Fig.18. The maximum lateral displacement for the new portal frames

In order to have a better evaluation of the lateral displacements and taking into consideration

the section sizes, a separate model has been created in which the portal frame has been modelled

with shell elements. The maximum lateral displacement obtain in this case was: δportal,frame = 26mm ≈ δbraced,frame = 27mm OK

Fig.19. The maximum lateral displacement for the new portal frames modelled with shell elements.

The capacity of the remaining top beams HEA 180: Governing Load Case: 6 ULS1: 1.35*DL+1.35*PL+1.50*LL+1.05WL (2+1)*1.35+3*1.50+4*1.05

SECTION PARAMETERS: HEA 180

h=171 mm gM0=1.00 gM1=1.00






Date: 30.08.2017 Page 24

INTERNAL FORCES AND CAPACITIES: N,Ed = 0.19 kN My,Ed = 29.49 kN*m

Nc,Rd = 1608.15 kN My,Ed,max = 29.49 kN*m

Nb,Rd = 462.14 kN My,c,Rd = 115.38 kN*m

MN,y,Rd = 115.38 kN*m Class of section = 2

----------------------------------------------------------------------------------------------------------------------------------------



Lcr,y = 5.42 m Xy = 0.62 Lcr,z = 5.42 m Xz = 0.29

Lamy = 72.82 kyy = 1.00 Lamz = 119.96 kzy = 0.52

----------------------------------------------------------------------------------------------------------------------------- -----------


My,Ed/My,c,Rd = 0.26 < 1.00 (6.2.5.(1))


N,Ed/(Xy*N,Rk/gM1) + kyy*My,Ed,max/(XLT*My,Rk/gM1) = 0.26 < 1.00 (6.3.3.(4))

N,Ed/(Xz*N,Rk/gM1) + kzy*My,Ed,max/(XLT*My,Rk/gM1) = 0.13 < 1.00 (6.3.3.(4))

The top steel beams HEA180 are safe after the introduction of the new portal frame ;

The capacity of the remaining steel post IPE400:


SECTION PARAMETERS: IPE 400 h=400 mm gM0=1.00 gM1=1.00




----------------------------------------------------------------------------------------------------------------------------- -----------

INTERNAL FORCES AND CAPACITIES: N,Ed = 42.37 kN My,Ed = 0.00 kN*m Vy,Ed = -0.32 kN

Nc,Rd = 2999.75 kN My,Ed,max = 0.00 kN*m Mz,Ed,max = 1.46 kN*m Vy,c,Rd = 1148.47 kN


MN,y,Rd = 463.99 kN*m Vz,c,Rd = 875.81 kN


----------------------------------------------------------------------------------------------------------------------------- -----------



Lcr,y = 13.49 m Xy = 0.61 Lcr,z = 4.72 m Xz = 0.31

Lamy = 81.51 kyy = 1.02 Lamz = 119.51 kzy = 0.53





----------------------------------------------------------------------------------------------------------------------------------------


My,Ed/My,c,Rd = 0.00 < 1.00 (6.2.5.(1))

Vy,Ed/Vy,c,Rd = 0.00 < 1.00 (6.2.6.(1))

Vz,Ed/Vz,c,Rd = 0.00 < 1.00 (6.2.6.(1))



Date: 30.08.2017 Page 25



N,Ed/(Xy*N,Rk/gM1) + kyy*My,Ed,max/(XLT*My,Rk/gM1) + kyz*Mz,Ed,max/(Mz,Rk/gM1) = 0.04 < 1.00 (6.3.3.(4))

N,Ed/(Xz*N,Rk/gM1) + kzy*My,Ed,max/(XLT*My,Rk/gM1) + kzz*Mz,Ed,max/(Mz,Rk/gM1) = 0.06 < 1.00 (6.3.3.(4))

The existing steel posts IPE400 are safe after the introduction of the new portal frame;

The capacity of the new steel post UB 406x178x67:


SECTION PARAMETERS: UB 406x178x67 h=409 mm gM0=1.00 gM1=1.00




----------------------------------------------------------------------------------------------------------------- -----------------------

INTERNAL FORCES AND CAPACITIES: N,Ed = 40.75 kN My,Ed = 0.00 kN*m Vy,Ed = -0.36 kN

Nc,Rd = 3035.25 kN My,Ed,max = 0.00 kN*m Mz,Ed,max = 1.63 kN*m Vy,c,Rd = 1102.37 kN


MN,y,Rd = 477.83 kN*m Vz,c,Rd = 789.89 kN


----------------------------------------------------------------------------------------------------------------------------- -----------



Lcr,y = 13.50 m Xy = 0.62 Lcr,z = 4.72 m Xz = 0.32

Lamy = 80.03 kyy = 1.02 Lamz = 118.25 kzy = 0.53





----------------------------------------------------------------------------------------------------------------------------- -----------


My,Ed/My,c,Rd = 0.00 < 1.00 (6.2.5.(1))

Vy,Ed/Vy,c,Rd = 0.00 < 1.00 (6.2.6.(1))

Vz,Ed/Vz,c,Rd = 0.00 < 1.00 (6.2.6.(1))



N,Ed/(Xy*N,Rk/gM1) + kyy*My,Ed,max/(XLT*My,Rk/gM1) + kyz*Mz,Ed,max/(Mz,Rk/gM1) = 0.04 < 1.00 (6.3.3.(4))

N,Ed/(Xz*N,Rk/gM1) + kzy*My,Ed,max/(XLT*My,Rk/gM1) + kzz*Mz,Ed,max/(Mz,Rk/gM1) = 0.06 < 1.00 (6.3.3.(4))

The structural design of the new portal frames:

From the foregoing analysis, we have been able to demonstrate that the new portalised frames can

adequately replace the existing flat plate bracings.

However, the detailed design of the portal members can only be completed following the indepth

discussions and co-ordination between the steel fabricator and ourselves. These discussions will take place

in the coming week and following these our detail calculations will be completed and made available for

review, comments and onward submission to the local authorities.



Date: 30.08.2017 Page 26

The structural impact on the existing foundation system:

As part of the desing process, the potential impact on the existing foundations has been

considered. The foundation system along gridlines 8 and 9 is made of a concrete ground beam,

1000m wide and 600mm deep, with pre-cast driven piles 320mmx320mm placed at 2.71 m centres.

Due to the steel bracings, locally, for the steel posts on gridlines G, H and I a local pile cap has

been provided. The pile cap is 2.0m long, 600mm wide and 600mm deep and it has 2 no. pre-cast

concrete driven piles. The ground floor slab of the warehouse has been desined as a heavy duty slab

and to withstand a load of 50kN/m2;

a) the shear forces at columns/steel posts bases:

Fig.20. The maximum shear forces for the columns/steel posts bases with flat steel bracings.

Fig.21. The maximum shear forces for the columns/steel posts bases with the new portal frames

VEd, max, bracings = 351.62 kN

VEd, max, portal frame = 366.02 kN

Δshear = 14.40 kN >> Λshear = 4.10 % slightly increase OK

b) the axial forces at columns/steel posts bases:

dkd

Toelichting

Shouldn't you take the loss of self-weight due to the removal of the wall also take in account here?



Date: 30.08.2017 Page 27

Fig.22. The maximum axial forces for the columns/steel posts bases with flat steel bracings.

Fig.21. The maximum shear forces for the columns/steel posts bases with the new portal frames

In case of the new portal frame, the concrete wall between the DC11 and DC12 will be

removed entirely. The selfweight of the concrete wall has the following value: Gwall = 0.15m·13.565m· 3.0m· 22 kN/m3= 134.20 kN

1.35·Gwall = 181.17 kN

NEd, max, bracings = 561.12 kN

NEd, max, portal frame = 582.12 kN

Δshear = 21.09 kN >> Λshear = 3.76 % slightly increase OK

The End of the structural report.

Prepared by:

Eng. Emilian Ursu (EU)

Checked by:

Eng. Martin Hyde (MH)

dkd

Toelichting

As I understood the wall is an AAC wall so the self-weight is much less. For your information the pile capacity is 750 kN.

Documents

STRUCTURAL DESIGN REPORT -Steel bracings … DESIGN REPORT -Steel bracings removal- Fokker Logistics Park– Amsterdam, Netherlands Revision History Rev. Date Designed by Checked by