Design of Multi-Story RC Building

Prepared By:Ahmed Abdulhameed Alimran431100204Mohammed Khalid Almahawis431101977Sattam Fahad Alshuwaier431100478

Supervised By: Co-advisors: Dr. Ahmet TKEN Prof. Talal O. Al-Refeai Dr. Khalid S. Al-Gahtani

Design of a Multi-Story RC Building

11Capstone Design Project2The purpose of this project is to design a commercial multi-story RC building located in Al-Sahafh district of Riyadh. The design steps are as follows:Calculating the loads.Designing the main structural elements; beam, slab, column.Calculating the bearing capacity of soil & designing the footing.Creating 3-D model using SAP 2000.Estimating the quantities and cost of the project using REVIT software.

OverviewOur building is a commercial multi-story RC building (offices and stores) located in Riyadh. The building is consisting of two floors (ground and first floor). Also, it has some offices on the roof of the building. The land area is 724 m2 and the building plan area is 563 m2.The area and the elevation of each floor are given below: 3Area (m2)Elevation (m)Ground563+ 0.45First616.4+ 3.45Offices on the roof292+ 6.45Ground Floor Plan4

First Floor Plan5

Roof Plan6

Main Design DescriptionThe design is carried out based on Saudi Building Codes.The building is constructed as in situ cast reinforced concrete (RC) structure.Floor system is considered as flat slab with beams.All walls are made of masonry blocks.

7Design Specifications- The following values were considered in our project: fc = 30 MPa fy = 420 MPa

- Floor system is flat slab with beams:

Load combination : Only dead load (DL) and live load (LL) were considered in our project. 1.4 (DL) + 1.7 (LL) (SBC 301-Eq. 2.3.2-2)

8Flat slab with beamsGeneral Load Calculation Dead Loads: Unit weight of concrete c = 24 KN/m3 Unit weight of wall b = 16.5 KN/m3 Slab thickness = 25 cm Slab weight = 0.25 * 24 = 6.0 KN/m2 Wall weight = 3.2 kN/m2 (From Table 3-1(a) in SCB 301)

Live Load (Based on SBC 301):

9 Lobby = 5 kN/m2 Corridor= 5 kN/m2 Office= 2.5 kN/m2 Kitchen = 2.5 kN/m2 Storage(light storage warehouse= 6 kN/m2 Roof(assembly purpose) = 5 kN/m2 Rest room= 3 kN/m2

General Load Calculation Superimposed Dead Load (SDL):

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Load on slab (first floor)11

Slab (Office)Load on Slab (Office) L1/L2 = 5200/3800 = 1.368 < 2 (two way slab) Weight of slab = 0.25 * 24 = 6.0 kN/m2. Total S.D load = 3.45 kN/m2. Total dead load = Weight of slab + Total S.D load = 6 + 3.45= 9.45 kN/m2

Live load = 2.5 kN/m2

Ultimate Load = 1.4D + 1.7L = 1.4 (9.45) + 1.7 (2.5) = 17.765 kN/m2

125.2 m3.8 mLoad on beam #1 (first floor)13

Beam #114

Load on Column15

Column #1Load on Column #116 Own weight=b * d * h * c= 0.8*0.25*9*24= 43.2 kN Own weight of column (after magnification) = 1.4*43.2 = 60.48 kN

Load from beam #1:Concentrated load on column =Total load on beam*length = 39.564 * 2.6 = 102.86 kNLoad from beam #2:Concentrated load on column =Total load on beam*length = 35.014 * 1.9 = 66.53 kNTotal concentrated load = 102.86 + 66.53 = 169.4 kNSince first & second floors are symmetric, then:Total concentrated load = 102.86 + 66.53 = 169.4 kNBy using the concept of tributary area, the load from Roof = 5.88 * 21.86 = 128.54 kNTotal load on column = Own weight +Load from first floor + Load from second floor + Load from roof = 60.48 + 169.4 + 169.4 + 128.54 = 527.82 kNDesign of Slab17

1819

20

-11.91 kN.m9.7 kN.m-3.23 kN.m-20.1 kN.m16.36 kN.m -0.98 kN.m-11.91 kN.m9.7 kN.m-3.23 kN.m1.0 m21The column strip is designed with the same procedure and the results are summarized as shown in the table:

Design of R.C beam #1 (First floor)22

Beam-to-slab stiffness ratio:f = 3.465 > 0.8 okl2/l1 = 4/4.75 = 0.842f*(l2/l1) = 3.465*0.842 = 2.92 > 123

Moments for Edge Beam (Beam#1):

Shear Design24

2526

Beam Detailing27Design of ColumnMoment acting on corner column:

Pu = 527.82 kN (calculated previously)(Mu)x = 1.46 kN.m(Mu)y = 1.41 kN.mLength of the column = L = 3 m (Short column)section ( 700 mm 200 mm)

212728Reinforcement

28GEOTECHNICAL PARTTable Spacing of the borings

Figure Spacing of the borings29

GEOTECHNICAL PART30Select the places of boreholes :

Design of footingGEOTECHNICAL PART(boring log)31

GEOTECHNICAL PART32GEOTECHNICAL PART33B=0.5mL/B=1.5From Table (5-2)From Figure (5-7) Design of footingFooting size:-

34qu=351.3 kN/m2b = 1m500mm200*700mmFigure (Factored net soil pressure)

Design of footingCheck thickness for tow-way shear:-35 Design of footing36Check for one- way shear :-One-way shear is critical at a distance (d) from the face of the column . ddCase1Case1Figure (Critical section for one way shear for the long and short directions)

Design of footing37Reinforcement design:-In long direction:

Figure (Critical section for long direction) Design of footing38 Design of footing39In short direction:

Figure (Critical section for short direction) Design of footing40In short direction:

Figure (Strips for the bar arrangement) Design of footing41 Design of footing42Design of dowels:-

Design of footing43 Design of footing44

Figure (Detailing of footing design)short sidelong sideSAP 200045

Designing the building using SAP 2000:

Defining the loadsDefining the materialsDefining the structural elementsCreating the modelDefining the load combinationsAssign the loadsCheck and run the model

SAP 2000 Animation46

47Design of selected beam (beam #1) in SAP 2000

Use 218mm bars for top and bottom reinforcement, (As,min = 333.67 mm2)

Use minimum shear reinforcement 8 mm stirrups @ 300 mm (48/m)48Design of selected column in SAP 2000Use 1014 mm bars, (As,min = 1400 mm2)

Use minimum tie reinforcement 10 mm ties @ 200 mm (510/m)

Design of selected slab in SAP200049For the slab design, the contour lines on the slab are used:

Slab with contour lines in y-direction for the long span designSafe range412/m (which is the minimum area of steel = 0.0018bh)(Mu = 37 kN.m)Comparison of Results50Beam #1:Column:Slab:Cost estimation using REVIT software51

REVIT software:

Autodesk REVITisa building information modelingsoftware for architects, structural engineers,MEP engineers, designers and contractors. It allows users to design a building and structure and its components in3D, annotate the model with 2D drafting elements, and access building information from the building model's database.REVIT software52

Our 3D Model53

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Structural column Schedule55

Total volume of concrete (from Revit) = 580.6 m356

From Construction Methods and Management By S.W.Nunnally (Eighth Eidition), the typical distribution of concrete construction costs as follow:

Cost assumptions57

Concrete cost (material+ driver+ assistance) = 200 SR/m3Total Cost58Concrete Material Cost = 580.6*200= 116,120 SRTotal Construction Cost = 116,120/0.24= 483,834 SR

59Thank You