hatleholparish _PRESENTATION_ MSc01 ARC group 6 december 2014
HATLEHOL PARISH
project period: 20.10.2014 - 17.12.2014 institute: Aalborg University department: Architecture, Design and Media Technology course: 1st Semester MSc Architecture & Design module: Tectonic Design: Structure and Construction
David Drazil
Calina Manisor
supervisor: Claus Kristensen technical supervisor: Dario Parigi group: 6
Pavlina Sedlakova
Nadia Skraeddergaard Frydkjaer
Helle Toft
3
ABSTRACT
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Dwelling upon a tectonic approach on architectural design, this proposal aims in triggering a sense of construability in the subliminal self of the visitor through the use of a carefully chosen architectural form, structural system and by meticulous considerations of the fabric of the existing realm. In the poetics of the framed nature, the proposal will function as a landmark within the local scene, opening a new range of opportunities for the Hatlehol locals, yet intervening as less as possible upon the existing morphology of the site by preserving the nowadays used outdoor seating area placed on the peak point of the site.
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CONTENTS
6
ABSTRACT
4
CONTENTS
6
THE CONCEPT
8
MATERIALITY
10
MASTERPLAN PLAN - LANDSCAPING PLAN - FURNITURE SECTIONS ELEVATIONS VISUALIZATIONS landmark by night rainy afternoon processional route ascendence in spirituality a warm melodious place
16 18 20 22 26 32 34 36 38 40
SUN LIGHT ANALYSIS daylight factor
42 44
ACOUSTICS development
46 48
STRUCTURE principle detailing
52 54 58
CONSIDERATION fire ventilation water collection
64 66 68 70
APPENDIX mezzanine floorplan structural analysis
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THE CONCEPT
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1_three volumes, three functional types
2_connection to the focal point, the peak
3_gesture of safety
4_sun to the courtyard
5_protection from wind
6_one origin for geometry
7_relation to human scale in courtyard
8_landmark from outside
9_movement towards ascending
10_complex connected by roof and form
11_framing views from courtyard
12_relationship to points of interest
13_inviting gesture to the complex
14_circulation in the courtyard
15_important functions at high endings
16_development for light, acoustic, structure 9
MATERIALITY
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EXTERIOR
LARCH WOOD CLADDING FOR ROOF AND FACADE
DARK METAL FRAMES AND DETAILS
ELONGATED GLAZED STRIPES
The decision of using this material has been made due to the local availability of the material as well as its colour. The colour works harmoniously with the surrounding natural environment, while the local availability provides a low carbon footprint, therefore appealing the sustainability of the project.
The use of this very deďŹ ned colour of the material contrast the neutral shades used in the proposal both in the interior and exterior of the complex. The choice has been made as to emphasize the framing of natural considerations such as light or surrounding landscape.
The shape of these windows accentuates the concept of ascendance, by providing an additional vertical movement on the facades, visible from both the interior, as well as the exterior. By using glazed surfaces with 75% opacity, the degree of light coming into the interior spaces is controlled and therefore creates a pleasurable environment for the user. 11
INTERIOR
12
BIRCH WOOD CLADDING
DARK METAL WINDOW FRAMES AND DETAILS
GLUE LAMINATED LOAD BEARING STRUCTURE
Because of the geographical positioning of the site, natural daylight hours are rather reduced. Therefore, the use of a light colour cladding for the interior spaces helps in achieving a more luminous interior space. Nonetheless, the availability of birch has also played an important role, as it is available at a local level.
The use of this very deďŹ ned colour of the material contrast the neutral shades used in the proposal both in the interior and exterior of the complex. The choice has been made as to emphasize the framing of natural considerations such as light or surrounding landscape. The material is also reproduced in the detailing of the Church room benches.
GL24h has been chosen as an accurate material for the structural elements of the composition because of its ability to span over large distances. GL24h stands for Glue Laminated Timber with a maximum allowable stress of 24 MPa and with a homogeneous composition.
INTERIOR FLOORING
DARK SLATE TILES
OAK FLOORING
WET CONCRETE
The material has been used as flooring in the most sacred spaces within the Church complex. The decision has been made with consideration to both aesthetic and technical aspects. The material references the relationship with the surrounding natural landscape, key feature of Nordic architecture, while the reflective properties of slate are preferable for the acoustics of the space.
Emphasizing on the initial intention of triggering a feeling of warmth and invitation in the perception of the visitor, the choice of using of oak flooring in the activity rooms has been made. Nevertheless, the decision also concerns more functional aspects such as durability, ease in cleaning or hypoallergenic properties.
With regard to the results of the climate analysis, revealing a predominantly wet atmosphere specific to the Alesund area, we have decided to use a material that interacts to the given climatic input. Therefore, wet concrete acknowledges our intention by offering a dynamic patter on the floor when wet. [flower pattern is illustrative] 13
THE PROPOSAL
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15
MASTERPLAN
16
0
10
20
30
40
50 m 17
PLAN LANDSCAPING
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0
10
20
30 m
19
PLAN FURNITURE
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
church room, 670 m2 technical room, 15 m2 additional sacristy, 13 m2 sacristy, 10 m2 sacristy for baptism, 45 m2 storage for hymn books, 15 m2 cloister room, 12 m2 church entrance hall, 50 m 2 cloakroom, 25 m2 children’s chapel, 75 m2 toilets, 12 m 2 storage, 35 m2 meeting room, 25 m2 chapel entrance, 20 m 2 chapel, 95 m 2
16 17 18 19 20 21 22 23
activity room, 30 m2 class room 1, 25 m2 class room 2, 25 m2 music room, 28 m2 cloak room, 20 m 2 toilets, 20 m 2 storage, 12 m2 entrance hall/library, 100 m2
C 2
3
A 4 5
1
7
10
9
6 8
C
B
12
13
11 34
15
14 31 33
30 32
A 29 28
24
B
27
16 24 25 26 27 28 29 30 31 32 33 34
workshop, 45 m toilets, 20 m 2 laundry room, 15 m2 meeting/dining room, 20 m2 offices, 50 m 2 technical room, 25 m2 entrance hall, 50 m 2 kitchen, 40 m2 storage, 12 m2 refuse, 12 m2 congregational hall, 150 m2 2
26 25
19 20 17
23
18
21
22
0
5
10
15 m
[see APPENDIX for the mezzanine floor plan]
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SECTIONS
22
ADMINISTRATIVE BUILDING SECTION
0
5
10
15 m
23
CHURCH BUILDING CROSS-SECTION
0 24
5
10
15
20
25 m
CHURCH BUILDING SECTION
0
5
10
15
20
25 m 25
ELEVATIONS
26
NORTH ELEVATION
0
5
10
15
20
25 m 27
SOUTH EAST ELEVATION
0 28
5
10
15
20
25 m
SOUTH WEST ELEVATION
0
5
10
15
20
25 m 29
SOUTH ELEVATION - CHURCH BUILDING
0 30
5
10
15
20
25 m
LANDMARK BY NIGHT
Upon arrival to the site of the Hatlehol Parish Complex from the main road, through the typical Northern raw natural scene and humbly above the peaks of the highest trees, the visitor acknowledges the inďŹ ltration of a somehow abstract silhouette that triggers his attention. This gesture is intended as guidance for the user towards the new Church complex, a place of worship and intimacy framed by the natural purity of the Alesund landscape. The proposal aims in achieving through its design and use a new landmark for the Alesund community.
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RAINY AFTERNOON
When arriving from the north, where the bus stops are situated, one can clearly recognize the highest point of the Church building. The whole complex is slowly opening towards the visitors when reaching the axis between the cemetery and the peak - focal point of the complex courtyard. The ďŹ rst building that grabs your attention is dedicated for the sacred functions. The volume is divided by a glazed strip into the Chapel and the Church. The Chapel is situated in the lower part of the building with close and intense relation to the cemetery. Even in uncomfortable weather conditions, so often experienced in this part of Norway, a warm inviting gesture, emphasized by natural materials on the facade, encourages the visitor to experience the complex and enjoy a safe shelter, while allowing a peaceful and ascending contemplation.
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PROCESSIONAL ROUTE
Visitors are encouraged to approach the Church complex through the South entrance placed close to the main parking spaces. The path to the inner courtyard is framed by the two non-sacred buildings, while creating an inviting visual axis with the most sacred space within the complex: the Church room. Walking towards the building complex, one passes by the bell tower and the entrance hall, which is clearly identiďŹ ed by the use of glass on the facade. The hall can be used as a gathering point for the users of this facility, in which information about events, books and the history of the place can be obtained.
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Entering further into the core of the complex, the visitor reaches the inner courtyard, perceived as an outdoor theatre. From this position, the viewer experiences a feeling of safety achieved through the curvature of the interior facades. The Church room stands out from the rest of the building because of the fragmented roof which appears as an intention of ascendance towards the skies.
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ASCENDENCE IN SPIRITUALITY
Placed under the highest peak of the building facade, the Church room exudes a feeling of ceremoniousness expressed through the use of a clear structural system that emphasizes the gradual increase of verticality towards the peak point of the Church volume. Although imposing through its height, the space expresses familiarity through the use of a birch cladding. Timidly inďŹ ltrating the interior space through systematically placed windows, white light livens up the otherwise dark room, while indicating the fractured movement of the structure towards the altar.
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Dwelling upon tectonic considerations, the altar wall has been shaped as a competing geometry to the layout of the church as to complete the dynamics of the space from an aesthetic view, while at the same time to redirect the sound towards the audience in a preferable acoustic scheme.
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A WARM MELODIOUS PLACE
Honesty and simplicity in design decisions are key characteristics in Northern architectural traditions. These features are clearly visible in the interior of the Church room, where the construing meets the constructed through a carefully chosen structural system that clearly outlines the architectural intention. Moreover, the layout and proportion of the Church room has proven ideal for acoustic considerations [see QRcode in ACOUSTICS section]. The choice in material for the ooring has been decided with consideration towards acoustic and aesthetic principles. The use of a reective material enhances the acoustic qualities of the space, while the choice in colour contrast the warmth of the walls by referencing the existing morphology of the site.
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SUN LIGHT ANALYSIS The morphological conďŹ guration of the three buildings of the complex is designed in a way which allows sunlight to reach the interior courtyard deďŹ ned by the three geometries. However, the outer space between the proposed buildings will not be fully shaded during the using hours between 10 am and 07 pm, from April to July. With consideration to the interior seating arrangement, the working areas have been placed in sunny areas, making these spaces a more pleasurable working environment.
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january 10am
january 01pm
january 04pm
january 07pm
april 10am
april 01pm
april 04pm
april 07pm
july 10am
july 01pm
july 04pm
july 07pm
october 10am
october 01pm
october 04pm
october 07pm
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DAYLIGHT FACTOR
As specified in the building code, daylight factor has been taken into account in each room with work-related functions. The analysis is made based on the height of a table, which is the surface of where the work will be performed. The results show that in all work zones there is at least a daylight factor of 2, which is demanded by the labor inspectorate under Danish law. The daylight factor in each room leads to optimum conditions for work.
windows are located to the north to avoid direct sunlight, as during service direct light can be accounted as a disturbing factor. The soft diffused light, which comes in the form of light from the sky, is the desired external light. In the church, the light must be a staging factor for the experience of space, compared to the classrooms and the office where the light is a function factor.
As seen in churches, there is a strong contrast between the ship’s two sides. One appears brighter. In order to emphasize the bright and achieve this, the contrast is required in the form of darkness. In this room, there are no special precautions to take in relation to their daylight factor. All
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diagram of analyzed rooms
church, perspective
church, daylight factor
church, lux factor
classroom, perspective
classroom, daylight factor
classroom, lux factor
office, perspective
office, daylight factor
office, lux factor
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ACOUSTICS
46
47
DEVELOPMENT
Tectonic design has been the main objective of the project, therefore the problematic of acoustics was taken into consideration in the development of the geometry of the Church Room. During the analysis, various iterations of the wall and roof conďŹ gurations have been tested. In spite of the fact that the original shape performed quite well in preliminary analyses, further studies have showed that a more fractured surface helped in breaking the continuity of the convex curvature of the outer wall. The shape of inner curvature remained the same.
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The curved altar wall has been introduced to help direct back sound reections to the audience. The selected degree of curvature has had the best results when analyzed with from the perspective of a receiver placed at the back of the space reserved for the audience. Therefore, it can be stated that even the auditor sitting on the back rows is able hear the priest clearly. The pictures on the right hand side illustrate sound distribution in the space. The cutting plane is made parallel to the outer wall in order to show the maximum height of the Church room.
church room oor plan
church room section
church room section
sound source - priest
sound source - priest
sound source - organ, choir
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FINAL RESULTS
10 ms
30 ms
50 ms
80 ms
10 ms
30 ms
50 ms
80 ms
10 ms
30 ms
50 ms
80 ms
[see APPENDIX for numerical results]
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CONCLUSION
For the final analysis, a simplified audience box-like shape has been introduced. As expected, a decrease in the magnitude of reverberation time has been noticed. However, the newly obtained values of Clarity, Loudness and Reverberation Time are still in the desired range. Although preceding analysis was mainly focused on numerical comparison and on the profile of the energy curve, the most important result achieved from the acoustic software is of subjective nature. Numerical results present relevant guidance on the way
from desired ambiance to final proposal. To be able to make final quality evaluation of the space, a recording of “Toccata and Fugue in D minor”, BWV 565 by Johann Sebastian Bach has been rendered. This recording represents the achievement of the objective which has been set at the preliminary stage - sacral ambiance related to the human scale. Final results in numbers have met requirements in the majority of cases, however, a subjective evaluation of auralized sound is still more important.
Scan the QRcode and listen to the church!
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STRUCTURE
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PRINCIPLE
The ďŹ nal proposal for the structural system is a synthesis between load bearing systems analysed in the preliminary stage. The chosen system consists of two structural parts which cooperate and mutually eliminate their weak features. Glue laminated timber frames are arrayed along the outline curve of the building. Dwelling upon a honest approach on the structural solution as to reect Northern traditions, the frames serve as the primary load bearing system. Rigid joints are designed as a solution for the frame lateral stability in plane.
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Due to three dimensional instability of discrete frames, the risk of buckling of the slender elements, and large cross-sections, a complementary structural system is introduced. Structural insulated panels (SIP) consist of two OSB sheets and a thick layer of thermal insulation which together serve as shear wall. The structural insulated panels cover the glue laminated frames on the exterior, protecting them from weather conditions, and connecting planar frames to create larger segments. Since frames are attached to shear planes along their height, the risk of buckling is eliminated.
These segments open the facade towards the exterior and emphasize the dynamic ascending movement along the focal point of the complex. Connection of segments is achieved through vertical and horizontal elements, which transfer the load to the main load bearing frame. This principle of connected fragments is similar to that of folding plates, characteristic for its excellent 3D stability and mutual cooperation of its components. Forces are distributed throughout the whole structure and internal forces in linear elements are smaller. Therefore, ďŹ nal cross-sections (and corresponding mass of the structure) can be smaller.
church building structure
rigid frames - glue laminated timber
various sections of frames due to
structural insulated panels
exterior view
simpliďŹ ed model for calculation
static reasons, light, ascending gesture
3d stability, no buckling, thermal insulation
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STATIC SCHEME AND LOADS
Taking into consideration the structural solution explained in the previous section the following scheme has been stressed. Each individual frame is constrained in the bottom points, the forces being transferred to concrete foundations. In terms of statics, these supports can be considered as external hinges [see DETAILING for joint details]. Moreover, internal glued joints in all standard frames are considered as rigid. The secondary frames above the window openings are pinned to the main load bearing frame, while also using vertical and horizontal connectors between the two mentioned frames.
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For the analysis of the structural behaviour of these elements, a number of load cases and their combinations (according to Eurocode formulas) were applied. Keeping in mind the placement of the proposed site: Alesund, Norway, consideration towards a high chance of snow fall and strong wind had to be stressed. Therefore, these loads have the most significant impact on internal forces. Leading from structural analysis in the FEM plug-in Karamba the final cross-section dimensions for the main frames have been decided at 1100x240 mm. These dimensions have been calculated for the
most stressed frame of the structure - on the second segment with the largest loaded area. Moreover, the final cross-section for the first smaller segment of the series is 700x240 mm, while the cross-sections for following segments would be designed in accordance with the decreasing internal stress. The calculated model in ROBOT is composed of a simplified proposed structural system to an acceptable level, therefore resulting an analysis for the most stressed elements of the series. The ratio of the designed and allowable stress in timber material is for the main frame 0.77 and for the smaller crosssection 0.78. [see APPENDIX for more details]
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DETAILING
The current chapter focuses on some of the most interesting and challenging details of the building from both architectural and structural point of view. Since the church building represents the ďŹ nal gesture of the movement on the site, emphasized by the height and facade fragmentation, it takes all the attention. The following pages contain drawings describing the facade in connection with both the ground and the roof structure. Moreover, important joints of the loadbearing frame are explained in relation to the static scheme. All the drawings should represent main principle of the structure with considerations to thermal insulation and water protection.
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DETAIL A
DETAIL B
SECTION PLANE
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2 INTERIOR BIRCH CLADDING
LATHS 40 x 50 mm
VAPOR BARRIER
STRUCTURAL INSULATED PANEL (SIP) OSB SHEET 20 mm INSULATION EPS 300 mm OSB SHEET 20 mm HYDRO INSULATION LAYER
ߔQJHU
2 LAYERS OF LATHS 40 x 50 mm
MATERIALS
EXTERIOR LARCH CLADDING
THERMAL INSULATION EPS
3 OSB SHEET ROOF LARCH CLADDING
2 LAYERS OF LATHS 40 x 50 mm
HYDRO INSULATION LAYER
STRUCTURAL INSULATED PANEL (SIP) OSB SHEET 20 mm INSULATION EPS 350 mm OSB SHEET 20 mm VAPOR BARRIER
LATHS 40 x 50 mm
INTERIOR BIRCH CLADDING
ߔQJHU
detail A - roof connection 60
0
1
2
3m
ߕRRULQ
ߔQLVKLQJ SURߔO
1 STONE FLOOR TILES (SLATE) OSB SHEET DOUBLE FLOOR FOR VENTILATION
OSB SHEETS 2 x 20 mm
MATERIALS
b
INSULATION EPS 300 mm
CONCRETE
HYDRO INSULATION LAYER
CONCRETE SLAB 150 mm THERMAL INSULATION EPS SPRINKLE SOIL
ORIGINAL SOIL RIGID FOAM INSULATION
ߕRRULQ
2 ORIGINAL SOIL INTERIOR BIRCH CLADDING
SPRINKLE SOIL
LATHS 40 x 50 mm
VKLQJ SURߔO
VAPOR BARRIER GRAVEL / PEA GRAVEL STRUCTURAL INSULATED PANEL (SIP) OSB SHEET 20 mm INSULATION EPS 300 mm
OSB SHEET
OSB SHEET 20 mm HYDRO INSULATION LAYER
2 LAYERS OF LATHS 40 x 50 mm
b
EXTERIOR LARCH CLADDING
detail B - plinth
0
1
2
3m 61
COLUMN TO SLAB JOINT
SELECTED COLUMN
plan
62
section A-A
section B-B
CONCLUSION
The most important feature of the proposed structure is that it works as a whole. Nonetheless, separate elements meet their requirements for static, acoustic or thermal insulation consideration. However, the aim is that through a tectonic approach and an integrated design process a successful solution is achieved when merging all components together. The departuring point for the design process has been in the formulation of the desired gestures, which strongly inuence the design through all its stages. In an effort to achieve the initial goals, as well as harmony among all structural
parts, a great number of analyses and explorations regarding statics, acoustics and lighting have been made. Conclusively, the end result is a structure which supports the concept and gestures, as well as the dynamic movement through facade fragmentation. This fragmentation permits light inďŹ ltration into the church room and positively inuences the acoustics of the geometry. Last but not least, the facade is made of structural insulated panels which ensure 3D stability and thermal insulation at the same time.
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CONSIDERATIONS
64
Consideration to ďŹ re, ventilation and water collection have been made from the early stages of the design process. The presented ows are only principles for how the above mentioned considerations could work, therefore there are no calculation of the size of the rain gutter or of the ventilation ducts which can determine the thickness of the wall and oor.
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FIRE
Considerations in relation to fire safety in the Church complex are accounted for in the design of the circulation routes within the complex. Fire cells divide the buildings in smaller sections, therefore meeting the standards for personal safety in evacuation and rescue. The building is provided with sprinkler and fire alarm systems. The sprinklers prevent the fire to spread and limit the fire damage. Because the load-bearing elements as well as the exterior classing are wood, the need for intumescent material to block the flames and delay the spread of fire is stressed.
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fire exit
Fire exit
fire unit Fire exit
exit route
Fire exit
Fire exit
Fire exit
Fire exit
Fire exit
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VENTILATION
For the church complex, it is desired to have a ventilation system where the air supply is demand driven, as there is a great variation in the density of users around the building. As the complex is divided into three building volumes, there will be a need for separate ventilation units. The design proposes a visible structure. Therefore, it will be necessary in most of the building to have the air supply unit in the oor and place the supply under windows or heaters along the external walls.
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Technical rooms
ventilation principle
double floor
vent
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WATER COLLECTION
Since the site is located on the western coast of Norway, near Ă…lesund, there is a high level of precipitation, both snow and rain. Therefore, it is important to consider a way in which water collecting could be solved. In this case, the shape of the buildings suggest a clear solution. Due to sufďŹ cient declination of the roof surface and the same direction towards the courtyard, water from all buildings can be collected around the inner perimeter of the complex. The roof of the church building is divided into several fragments and each has its own rainwater spouting and downspout. On the other hand, the roofs of the other two buildings are more continuous therefore leading to a smaller area, which allows to use just three mutual downsprouts for each building.
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perspective view - declination and direction of roof surfaces
downspout rainwater spouting declination of the roof
plan - declination and piping
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APPENDIX
MEZZANINE FLOORPLAN
0
5
10
15 m
STRUCTURAL ANALYSIS
In order to analyze the behaviour of the structural system in Autodesk Robot Structural Analysis Professional 2014, various load cases have been determined. All calculations have been made according Eurocode formulas. All loads are considered as static, ďŹ xed actions acting directly on the structure. Loads cases were combined according to the formula for Ultimite Limit State (ULS) and resulting internal forces were used for calculations regarding the design stress in material. The Serviceability Limit State (SLS) combination formula was applied to the load cases for the purpose of deformation analysis.
GENERAL CONDITIONS
Load duration classification and moisture content in timber material are considered to be important for its stiffness. Therefore, these conditions have to be taken into account when calculating strength of timber structures. RELEVANT LOAD DURATION CLASSES (Eurocode 5.1.1., p. 22) _permanent - self-weight of structure - roof self-weight _short-term - snow _instantaneous - wind SERVICE CLASS (Eurocode 5.1.1., p. 22) _service class 1 - temperature 20°C and relative humidity of the surrounding air only exceeding 65% for a few weeks per year PARTIAL FACTORS (Eurocode 0, p. 51, 98) _partial factor for permanent action - γG = 1.35 _partial factor for variable action - γQ = 1.5
_factor for combination value of a variable action - ψ0 = 0.7 _factor for frequent value of a variable action - ψ1 = 0.7 _factor for quasi-permanent value of a variable action - ψ2 = 0.7
MATERIAL PROPERTIES MATERIAL - GL24h (Teknisk Ståbi, 2011, table 7.1, p. 314) _density - 380 kg/m3 = 3.8 kN/m3 _characterictic values of strenght - fm,k = 24 MPa - ft,0,k = 16.5 MPa - ft,90,k = 0.4 MPa - fc,0,k = 24 MPa - fc,90,k = 2.7 MPa _characterictic values of elasticity module - E0,k = 11.6 GPa _characterictic values of shear module - G = 0.72 GPa _design values (Eurocode 5.1.1., p. 27) - fd = (fk*kmod)/ γM γM = 1.25 (glue laminated timber) kmod = 1.1
SNOW LOAD
LOADED WIDTH - FRAMES
walls roof
WIND LOAD
ÅLESUND, < 100 m alt.
1m 1m
(http://snofangerkroken.no/sider/lastkalk7.php#)
ROOF SELF-WEIGHT LOAD Roof structure consist of Structural Insulated Panels (SIP) which provide the strcture with 3D stiffness and thermal insulation. At the same time, SIPs distribute internal forces in the structure what eliminates buckling for tall slender elements and in the same time allows smaller dimensions of sections. _OSB sheet 2x 60 kN/m3 - th. 20 mm _EPS foam 3 kN/m3 - th. 350 mm _laths 51 kN/m3 - 2*50*30 mm _roof cladding - timber 50 kN/m3 - th. 20 mm
0.100 kN/m2
total line load calculation
0.500 kN/m2
sk = 3kN/m2
_basic wind velocity vb,0 vb,0 = 27 m/s z0 = 0.003 m (seafront) ce(z) = 2.1 _peak velocity pressure qp (z) = ce (z) * 0.5 * ρair * vb2 qp (z) = 2.1 * 0.5 * 1.25 * 272 = 0.957 kN/m2
_snow load arrangement (Eurocode 1.1.3, p. 18)
s = μi * Ce* Ct *sk μ1 = 0.8 s = 0.8 * 1 * 1 * 3 =
2.4 kN/m2
_line load 2.4 kN/m2 *1 m =
2.4 kN/m
_external pressure coefficients (Eurocode 1.1.4)
0.120 kN/m2 0.105 kN/m2 0.015 kN/m2
_line load on element (1 m loaded width) fD = qp (z) * D * 1 fD = 0.975 * (+ 0.8) * 1 = fE = qp (z) * E * 1 fE = 0.975 * (- 0.4) * 1 = fH = qp (z) * H * 1 fH = 0.975 * (- 0.8) * 1 =
+ 0.765 kN/m2 - 0.383 kN/m2 - 0.765 kN/m2
ROBOT CALCULATION RESULTS
EXPLANATORY FRAME
For structural analysis, simplified model was used. Due to software limitation, structural panels could not be applied - cross bracing elements were used to substitute panels preserving the same effect on 3D stability. Preliminary analysis from Karamba FEM plugin confirmed prediction regarding various requirements for dimensions of cross-section. Final dimensions were calculated for main load bearing frames and for the most stressed frame from the group of frames designed with smaller dimensions. Simplified principle is described on illustrations.
position in structure
designed principle
simplified principle
robot model
STRUCTURAL BEHAVIOUR DESCRIPTION _tall column Stress in the tall column is mainly caused by normal force which is acting in the direction of the central axis of element. This behaviour is predictable because applied load has predominantly vertical direction. Resulting normal force is slightly larger at the bottom point which is caused by self-weight of this element. The other significant internal force is bending moment which dominant part is transferred from the beam through rigid joint. Moment is always equal to zero at hinge type support. _small column This column is primarilly stressed by transferred bending moment as the previous element. _beam Normal force in this element is caused by lateral windload. Dominant force is the bending moment which expectedly has high values at the ends (rigid joints) and in the middle of the span.
INTERNAL FORCES - DIAGRAMS
ACOUSTIC RESULTS