Structural Planning of Reinforced Concrete Building based on SNI-1726-2019 and SNI-2847-2019
(Case Study of 8 Floor Apartment Building Bekasi South City)
Ahmad Rif’an Hanifudin, Agyanata Tua Munthe Department of Civil Engineering, Mercu Buana University
Jakarta, Indonesia
[email protected], [email protected]
Abstract
Bekasi City is one of the cities in the province of West Java, Indonesia. Bekasi City is one of the supporting cities for the capital city of DKI Jalarta and is part of the Jabodetabek megapolitan or as a satellite city with the largest population in Indonesia. This apartment building is expected to meet residential needs in the densely populated city of Bekasi with limited residential land. In this study the method used is structural planning using the applicable reinforced concrete structural planning regulations and using software to analyze the apartment building. This apartment is designed using the Special Moment Bearing Frame System (SRPMK) based on the Procedure for Calculation of Concrete Structures for Buildings (SNI–2847–2019). Analysis of earthquake loads using the static equivalent method based on the Procedure for Planning for Earthquake Resistance for Building and Non-Building Structures (SNI–1726–2019). The planning of the building which has 8 floors includes the planning of columns, beams, floor plates and stairs. The results of calculations and analysis obtained column dimensions in accordance with the requirements of SNI-2847:2019 K1:700x700 millimeters, K2:600x600 millimeters and K3:400x400 millimeters, beam dimensions B1:500x700 millimeters, B2:300x400 millimeters, and B3:250x350 millimeters, the dimensions of the floor slab are 120 millimeters thick.
Keywords:
Apartments, Beams, Columns, Designs, Floor Slabs.
1. Introduction
An apartment is a building that is divided into several rooms or groups of rooms separated by partitions and used as a residence. Apartments are one type of residence other than hotels that are in great demand by the public, especially people who live in big cities. Apartments provide various facilities and conveniences for their customers, this has an impact on increasing public interest in apartments. The analysis was carried out with a case study on the 8-floor Apartment Building Bekasi South City. This research includes designing the structure of columns, beams, plates. Later the planning will refer to the Procedure for Calculation of Earthquake Resistant Structures (SNI 1726 – 2019), and Procedures for Calculation of Concrete Structures for Buildings (SNI 2487-2019).
1.1. Identification of problems
Based on the above background, several problems can be identified as follows:
1. It is necessary to analyze the maximum load held by the building structure.
2. It is necessary to analyze the dimensions of the structure capable of bearing the load.
1.2. Research Purposes and Objectives
In this writing the aims and objectives of this research are:
1. Knowing the maximum load held by the building structure.
2. Knowing the dimensions of the structure that is able to bear the load from the results of calculations in planning.
2. Methodology
The research method is the stages or procedures for carrying out research in a scientific way with the aim of obtaining answers to the research problems proposed in the writing of the Final Project with a systematic description of the stages.
In this research, the method used is data analysis method, which is one of the important components in the Data Analysis process. The data analysis method is part of the analysis process where the data collected is then processed to produce conclusions in decision making. Structural planning using the applicable reinforced concrete structure planning regulations and using Etabs Software to analyze Apartment Buildings. In planning the standard apartments used are structural concrete requirements for buildings (SNI-2847-2019) and procedures for planning earthquake resistance for building and non-building structures (SNI-1726-2019).
2.1. Slab Design
Reinforced concrete slab is a structure made of reinforced concrete with a horizontal plane, and loads acting perpendicular to the plane of the structure. The slab reinforcement planning system is basically divided into 2 types, namely one-way slab and two-way slab.
Table 1. Minimum Thickness of One Way Slab SNI 2847:2019
Minimum thickness of non-prestressed one-way solid plate
Focus Condition h[1] Minimum
Simple focus L/20
One end continuously L/24
Both ends continuous L/28
cantilever L/10
Source:(SNI 2847, 2019)
Table 2. Minimum Thickness of Two Way Slab SNI 2847:2019
Minimum thickness of non-prestressed tow-way solid plate
fy' MPa[2]
No drop panels[3] With drop panels[3]
Exterior panels Interior panels
Exterior panels Interior panels No
edge beam
With edge beam[4]
No edge beam
With edge beam[4]
280 Ln/33 Ln/36 Ln/36 Ln/36 Ln/40 Ln/40 420 Ln/30 Ln/33 Ln/33 Ln/33 Ln/36 Ln/36 520 Ln/28 Ln/31 Ln/31 Ln/31 Ln/34 Ln/34
Source:(SNI 2847, 2019)
2.2. Beam Design
Beams are structural components that are in charge of transmitting self-supported loads or from plates to supporting columns. The beam resists the forces acting in a transverse direction to its axis which results in bending.(Dipohusodo, 1993)
Table 3. Minimum Beam Thickness
SNI 2847:2019 - Minimum height of non-prestressed beam
Placement conditions Minimum h[1]
Simple laying L/16
Menrus one side L/18.5
Menrus two sides L/21
cantilever L/8
Source:(SNI 2847, 2019)
2.3. Column Design
Columns are structural elements that resist axial forces and bending moments. In principle, the column is a vertical compression member of a structural frame that carries the load from the beam. Columns transmit loads from the upper elevation to the lower elevation until they reach the ground through the foundation.
Initial designing Column described based on SNI 2847 – 2019 article 18.7.2.1:
3. The dimensions of the shortest cross-section, measured on a straight line through the center of the geometry, shall not be less than 300 mm.
4. The ratio of the dimensions of the shortest section to the perpendicular dimension shall not be less than 0.4 .
2.4. Loading Combination
The load combination is desinged in accordance with SNI 2847:2019 article 5.3.1, namely:
1. U = 1.4 D
2. U = 1.2 D + 1.6 L + 0.5 (Lr or R)
3. U = 1.2 D + 1.6 (Lr or R) + (1.0 L or 0.5 W) 4. U = 1.2 D + 1.0 W + 1.0 L + 0.5 (Lr or R) 5. U = 1.2 D + 1.0 E + 1.0 LU = 0.9 D + 1.0 W 6. U = 0.9 D + 1.0 E
3. Results and Analysis
In this section, steps are taken in the form of making an initial design of the design structure with the following technical specifications:
1. F'c = 30 N/mm² 2. Fy = 420 N/mm²
3.1. Structural Modeling Using Etabs Software
Structural modeling uses 3D open frames. Analysis is done by modeling building structures starting from columns, beams, slab, and other building structures into the Etabs Structural Analysis software.
Table 4. Etabs Software Modeling Data
Building Description Information
Structural System SRPMK
Building Function Apartment
Number of Floors 8 floors
Highest and Lowest Elevation + 35.00 from 0.00
Typical Floor Height 4m
Vertical Connector Stairs and Elevator
Source: Data in research, 2021
Figure 1. 3D Modeling to ETABS Source: Data in research, 2021
3.2. Earthquake Load Analysis
a. Parameters of acceleration of the MCE spectral response from the earthquake map in a period of 0.2 seconds (Ss)
Figure 2. MCE Spectral Response Acceleration Parameters
Ss = 0.8368 g (Based on the Indonesian Spectra Design Application Puskim,pu,go,id)
b. Parameters of acceleration of the MCE spectral response from the earthquake map in a period of 1 second (S1)
Figure 3. MCE Spectral Response Acceleration Parameters Source :(SNI 1726, 2019)
S1 = 0.3942 g (Based on the Indonesian Spectra Design Application Puskim,pu,go,id) c. Long period transition (TL)
Figure 4.Long Period Transition (TL) Source :(SNI 1726, 2019) SL = 20 seconds
d. Type of soil
SE (soft soil) → Assumption of soil type obtained from Bekasi area soil analysis 1) Site Class = SE (Land soft)
2) Vs = < 175 m/second 3) N or Ncb = < 15
4) S = < 50 kPa
Figure 5. Bekasi Area Spectrum Response Graph Source: Data in research, 2021
Obtained:
Building risk category (I) = II Priority factor for earthquake (Ie) = 1.00 Seismic Design Category = D Because D is used SRPMK structure system System and structure parameters
R = 8
CD = 5.5
Ω 0 = 3
Natural period of structure (Cu) = 1.4 T use = 1.05 sec
Kx = 0.9
Vstatic = 6567.79 KN
T 0 0.27
T0 0.18 0.69 Ts 0.92 0.69 T 1.5 0.42
T 2 0.32
T 3 0.21
T 5 0.13
T 8 0.08
T 12.0 0.05 T 14 0.05 T 16 0.04 T 18.0 0.04 TL 20.0 0.03 T 22.0 0.03 Sa ( g ) Periode
(detik)
0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8
0 5 10 15 20 25
BEKASI AREA SPECTRUM RESPONSE GRAPH
Sa (g )
Period ( sec )
3.3. Plate Calculation
a. Calculation of plate moment
The value of the moment plate acting on the floor slab is determined by the Moment Coefficient Table PBI- 1971, Table 1, slab 2 conditions,
Slab moment coefficient, for Ly/Lx = 1.2 → Two-way plate
Mlx = 46 Mtx = 46
Mly = 38 Mty = 38
1. X direction field moment
Mlx = 0.001 x Qu x Lx² x Coefficient = 34,186 kNm 2. Y direction field moment
Mly = 0.001 x Qu x Ly² x Coefficient = 40,667 kNm 3. Moment of support in the direction X
Mtx = 0.001 x Qu x Lx² x Coefficient = 34,186 kNm 4. Y direction support moment
Mty = 0.001 x Qu x Ly² x Coefficient = 40,667 kNm b. Calculation of slab bending reinforcement
Direction field reinforcement X 1. Nominal moment (Mn)
Mn need = Mu / = 22902250 Nmm 2. Minimum reinforcement ratio
ρ min = 1.4 / fy = 0.0036 3. Maximum reinforcement ratio
ρ max = 0.75 x bp = 0.0236 4. Reinforcement ratio is necessary
Rn =
= 2.62
ρ = ( √ ) = 0.0071 ρ min < ρ < max,
then used = ρ = 0.0071
1) Reinforcement area required Ace need = p used xbx dx = 667 mm² S need =
= 199 mm
S Wear = 150 mm
Then use reinforcement, D13-150
2) Check the distance between reinforcement 150 < 3h < 450
150 < 360 < 450 OK Direction field reinforcement Y 1. Nominal moment (Mn)
Mn need = Mu / φ = 27243720 Nmm 2. Minimum reinforcement ratio
ρ min = 1.4 / fy = 0.0036 3. Maximum reinforcement ratio
ρ max = 0.75 x ρb = 0.0236 4. Reinforcement ratio is necessary
Rn = = 4.2
ρ =
( √ ) = 0.0119 ρ min < < max,
then used = = 0.0119 5. Reinforcement area required
Ace need = used xbx dx = 926 mm² S need =
= 138 mm
S use = 100 mm
Then use reinforcement, D13-100
6. Check the distance between reinforcement 100 < 3h < 450 100 < 360 < 450 OK
Figure 6. Typical Details of Slab Reinforcement Source: Data in research, 2021
3.4. Beam Calculation
Positive Design Moment Due to Factored Load Mu = 434.553 kNm Negative Design Moment Due to Factored Load Mu = 609.381 kNm Design Shear Force Due to Factored Load Vu = 332.886 kN Design Torque Moment Due to Factored Load Tu = 114.089 kNm
Reduction factor for Transitional reinforced structural components = 0.8 (SNI 2847 - 2019 Article 21.1) Reinforcement ratio
ρ min < ρ need < ρ max
0.002 < 0.0097 < 0.025 → Use ρ need Design Moment
Mn > Mu
670,675 > 609,381 OK
Table 5. Beam Reinforcement Recapitulation
Source: Data in research, 2021
Figure 7. Typical Cuts of Beam Reinforcement Source: Data in research, 2021
3.5. Column Calculation
Positive Design Moment Due to Factored Load Mu = 601,751 KNm Factored Load Design Axial Force Pu = 5971,528 KN Design Shear Force Due to Factored Load Vu = 267,861 KN Design Torque Moment Due to Factored Load Tu = 3.122 KNm Check section
Pn max > .Pn > Pu
12475.71 > 7153.69 > 5971,528 OK Check Sliding Reinforcement
1/2.ϕVc Vu Vc
29145.62 > 267.86 < 58291.24
Install Minimum Shear Reinforcement
fy = 420 MPa fc = 30 MPa pmin = 0.0018 pmaks =
Mu d' d Rn As Asada a ϕ Mn
kNm b (mm)
h
(mm) dtlg ds (mm) (mm) MPa mm2 npakai Jenis Dia. mm2 mm kNm
M+ 410.98 500 700 25 10 40 62.5 637.5 16.47 2.53 0.0064 0.0064 2024.57 4.12 5 D 25 2454.37 80.85 615.486 Aman Satu Baris M- 553.29 500 700 25 10 40 62.5 637.5 16.47 3.40 0.0087 0.0087 2783.16 5.67 6 D 25 2945.24 97.02 728.582 Aman Satu Baris M+ 434.55 500 700 25 10 40 62.5 637.5 16.47 2.67 0.0067 0.0067 2147.92 4.38 5 D 25 2454.37 80.85 615.486 Aman Satu Baris M- 609.38 500 700 25 10 40 62.5 637.5 16.47 3.75 0.0097 0.0097 3091.91 6.30 7 D 25 3436.12 113.19 838.344 Aman Satu Baris M+ 406.20 500 700 25 10 40 62.5 637.5 16.47 2.50 0.0063 0.0063 1999.69 4.07 5 D 25 2454.37 80.85 615.486 Aman Satu Baris M- 602.86 500 700 25 10 40 62.5 637.5 16.47 3.71 0.0096 0.0096 3055.72 6.23 7 D 25 3436.12 113.19 838.344 Aman Satu Baris M+ 368.34 500 700 25 10 40 62.5 637.5 16.47 2.27 0.0057 0.0057 1803.66 3.67 4 D 25 1963.50 64.68 499.056 Aman Satu Baris M- 573.39 500 700 25 10 40 62.5 637.5 16.47 3.53 0.0091 0.0091 2893.15 5.89 6 D 25 2945.24 97.02 728.582 Aman Satu Baris M+ 373.17 500 700 25 10 40 62.5 637.5 16.47 2.30 0.0057 0.0057 1828.53 3.73 4 D 25 1963.50 64.68 499.056 Aman Satu Baris M- 543.59 500 700 25 10 40 62.5 637.5 16.47 3.34 0.0086 0.0086 2730.40 5.56 6 D 25 2945.24 97.02 728.582 Aman Satu Baris M+ 373.09 500 700 25 10 40 62.5 637.5 16.47 2.30 0.0057 0.0057 1828.15 3.72 4 D 25 1963.50 64.68 499.056 Aman Satu Baris M- 499.62 500 700 25 10 40 62.5 637.5 16.47 3.07 0.0078 0.0078 2493.08 5.08 6 D 25 2945.24 97.02 728.582 Aman Satu Baris M+ 373.31 500 700 25 10 40 62.5 637.5 16.47 2.30 0.0057 0.0057 1829.25 3.73 4 D 25 1963.50 64.68 499.056 Aman Satu Baris M- 447.84 500 700 25 10 40 62.5 637.5 16.47 2.75 0.0070 0.0070 2217.86 4.52 5 D 25 2454.37 80.85 615.486 Aman Satu Baris M+ 268.21 500 700 25 10 40 62.5 637.5 16.47 1.65 0.0041 0.0041 1295.49 2.64 3 D 25 1472.62 48.51 379.293 Aman Satu Baris M- 384.83 500 700 25 10 40 62.5 637.5 16.47 2.37 0.0059 0.0059 1888.77 3.85 4 D 25 1963.50 64.68 499.056 Aman Satu Baris
0.025
BI Story 4 BI Story 5 BI Story 6 BI Story 7 BI Story 8
Cara Pemasanga
n Tipe
Balok Arah
Ukuran Tulangan
ρpakai nada
ts m
BI Story 1 BI Story 2 BI Story 3
ρpe rlu
Penulangan
Cek
Table 6. Column Reinforcement Recapitulation
Source: Data in research, 2021
Figure 8. Typical Details of Column Reinforcement Source: Data in research, 2021
4. Conclusion
Based on the results of the analysis of the structural calculations that have been desinged in the previous chapter, it can be concluded that several designing results are in accordance with the formulation of the problem as follows:
ϕ = 0.75 fc = 30MPa fys = 280 MPa
Pu Vu d' d ϕVc Vs Vsmin Vsmaks 1/2.ϕVc Avsada Sada
kN kN b
(mm) h
(mm) dtlg ds (mm) (mm) KN KN kN KN KN (mm2) (mm) ds - S
K1 Story 1 5971.53 235.18 700 700 25 10 40 62.5 637.5 582.912 313.568 148.75 1629.47 291.456Tidak Perlu Tul. Geser 157.08 188.50 10 - 175 K1 Story 2 5468.72 241.74 700 700 25 10 40 62.5 637.5 560.071 322.317 148.75 1629.47 280.035Tidak Perlu Tul. Geser 157.08 188.50 10 - 175 K1 Story 3 4562.56 267.86 700 700 25 10 40 62.5 637.5 518.906 357.147 148.75 1629.47 259.453Pasang Tulangan Geser Minimum 157.08 188.50 10 - 175 K1 Story 4 3673.45 244.53 700 700 25 10 40 62.5 637.5 478.515 326.039 148.75 1629.47 239.257Pasang Tulangan Geser Minimum 157.08 188.50 10 - 175 K2 Story 5 2800.53 202.59 600 600 25 10 40 62.5 537.5 350.361 270.123 107.50 1177.60 175.180Pasang Tulangan Geser Minimum 157.08 219.91 10 - 200 K2 Story 6 1964.99 183.06 600 600 25 10 40 62.5 537.5 313.024 244.077 107.50 1177.60 156.512Pasang Tulangan Geser Minimum 157.08 219.91 10 - 200 K2 Story 7 1160.47 148.60 600 600 25 10 40 62.5 537.5 277.073 198.125 107.50 1177.60 138.537Pasang Tulangan Geser Minimum 157.08 219.91 10 - 200 K2 Story 8 522.33 114.27 600 600 25 10 40 62.5 537.5 248.557 152.360 107.50 1177.60 124.279Tidak Perlu Tul. Geser 157.08 219.91 10 - 200 K3 Story 1 1332.77 29.99 400 400 25 10 40 62.5 337.5 150.370 39.985 45.00 492.95 75.185Tidak Perlu Tul. Geser 157.08 329.87 10 - 250 K3 Story 2 1180.34 34.82 400 400 25 10 40 62.5 337.5 143.955 46.415 45.00 492.95 71.977Tidak Perlu Tul. Geser 157.08 329.87 10 - 250 K3 Story 3 990.56 32.62 400 400 25 10 40 62.5 337.5 135.967 43.482 45.00 492.95 67.984Tidak Perlu Tul. Geser 157.08 329.87 10 - 250 K3 Story 4 814.59 27.83 400 400 25 10 40 62.5 337.5 128.561 37.099 45.00 492.95 64.281Tidak Perlu Tul. Geser 157.08 329.87 10 - 250 K3 Story 5 644.16 32.94 400 400 25 10 40 62.5 337.5 121.388 43.919 45.00 492.95 60.694Tidak Perlu Tul. Geser 157.08 329.87 10 - 250 K3 Story 6 466.06 24.62 400 400 25 10 40 62.5 337.5 113.892 32.820 45.00 492.95 56.946Tidak Perlu Tul. Geser 157.08 329.87 10 - 250 K3 Story 7 295.29 17.29 400 400 25 10 40 62.5 337.5 106.705 23.045 45.00 492.95 53.353Tidak Perlu Tul. Geser 157.08 329.87 10 - 250 K3 Story 8 173.88 15.16 400 400 25 10 40 62.5 337.5 101.595 20.209 45.00 492.95 50.798Tidak Perlu Tul. Geser 157.08 329.87 10 - 250 Penulangan Tulangan
ts Cek
Tipe Balok
Ukuran Kolom
1. The building that has been designed on a beam structure is able to bearing loads with positive design moment due to factored load Mu = 434.553 kNm, negative design moment due to factored load Mu = 609.381 kNm, design shear force due to factored load Vu = 332.89 kN, design torque moment due to factored load Tu = 114,089 kNm. The column structure is able to bearing loads with positive design moment due to factored load Mu = 601,751 kNm, axial force due to factored load Pu = 5971,528 kN, design shear force due to factored load Vu = 267,861 KN, design torque moment due to factored load Tu = 3,122 KNm.
2. Based on the results of the structural element design, the dimensions of the beams in accordance with the requirements of SNI 2847:2019 article 9.3.1.1 are B1 500/700 mm, B2 300/400 mm, B3 250/350, column dimensions in accordance with the requirements of SNI 2847:2019 article 18.7.2.1 are K1 700/700, K2 600/600mm, K3 400/400 mm, the thickness of the slab according to the requirements of SNI 2847-2019 article 7.3.1.1 is 120 mm. The structure is capable of bearing loads with the reinforcement configuration on each structural element.
References
Dipohusodo, I. (1993). Struktu Beton Bertulang SK. SNI T-15-1991-03. 1–527.
SNI 1726. (2019). Tata Cara Perencanaan Ketahanan Gempa Untuk Struktur Bangunan Gedung dan Non Gedung.
Badan Standarisasi Nasional.
SNI 2847. (2019). Persyaratan Beton Struktural Untuk Bangunan Gedung Dan Penjelasan. Badan Standarisasi Nasional.
