STRUCTURAL EVALUATION OF DAMAGED BRI BRANCH OFFICE BUILDING AT JALAN KHATIB SULAIMAN PADANG DUE TO EARTHQUAKE

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International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 10, October 2017, pp. 1170 1180, Article ID: IJCIET_08_10_120 Available online at http://http://www.iaeme.

1 International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 10, October 2017, pp , Article ID: IJCIET_08_10_120 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed STRUCTURAL EVALUATION OF DAMAGED BRI BRANCH OFFICE BUILDING AT JALAN KHATIB SULAIMAN PADANG DUE TO EARTHQUAKE Zaidir Civil Engineering Department Faculty of Engineering, University of Andalas, Padang, Indonesia Fauzan Civil Engineering Department Faculty of Engineering, University of Andalas, Padang, Indonesia Abdul Hakam Civil Engineering Department Faculty of Engineering, University of Andalas, Padang, Indonesia Febrin Anas Ismail Civil Engineering Department Faculty of Engineering, University of Andalas, Padang, Indonesia ABSTRACT The earthquake 30 September 2009 in West Sumatera has caused damage to many buildings in Padang City, Indonesia. One of building that also suffered severe damage is BRI branch office which is located at Jalan Khatib Sulaiman Padang. This paper discussed the structural evaluation of damaged BRI branch office building whether it can be used again or not. Evaluation was done on non-structural and structural elements of the building. The structural analysis was used ETABS program ver with properties of material is taken from the test results of existing structures. The standard code is used is Earthquake Resilience Planning Standard for Building Structure 2002 (SNI ) and the Hazard map Indonesia earthquake in 2010 with location of Padang city. From the results of the evaluation it was found that the building is not structurally feasible and recommended not to be use or to be destroyed Keywords: Earthquake 30 September 2009, structural evaluation, non-structural and structural elements editor@iaeme.com

2 Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail Cite this Article: Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail, Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due to Earthquake, International Journal of Civil Engineering and Technology, 8(10), 2017, pp INTRODUCTION The BRI branch office building located on Jalan Khatib Sulaiman Padang is one building that suffered severe damage due to tectonic earthquake of 7.9 SR which occurred on September 30, 2009 in West Sumatera. The earthquake has resulted various damages both facilities and physical infrastructure and casualties on various area in West Sumatera Province. Based on data published by Satkorlak PB West Sumatra and BNPB were known the facilities and infrastructure sector loss reached Rp. 963 billion. The education sector also suffered damage due to the earthquake. A total of 1,384 school buildings were heavily damaged, 1,018 were moderately damaged and 744 were slightly damaged with damage value of Rp.588,7 billion (Fauzan, 2012). The structural evaluation of the BRI branch office is intended to conduct the structural evaluation of the building, is it still feasible to be used or not. The evaluation was conducted on the existing building condition and the necessary data for structural analysis is taking directly. The dimension of structural elements buildings such as columns, beams and plates are obtained from as built drawings and a concrete quality using a hammer test. The structural analysis using computer simulation of ETABS program ver A building code used the Earthquake Resilience Planning Standard for Structures Building 2002 (SNI ) and The Hazard map of Indonesia earthquake in 2010 with the location of Padang city, West Sumatera. The bearing capacity of the foundation was evaluated using the data of DCP (Ducth Cone Penetrometer) 2. BUILDING GENERAL DATA 2.1. Building Data The three floors of BRI branch office building is a rectangular RC frame with size of 19,20 m x 24,00 m. Figure 1 and 2 show the lay-out of building and the beam column position of second, third and roof floors. Table 1 shows a column and beam dimensions of building. Figure 1 Building lay-out and columnbeam position at 2 nd and 3 rd floor Figure 2 Building lay-out and columnbeam position at roof floor editor@iaeme.com

3 Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due to Earthquake Tabel 1 Column and beam dimensions of building Floor Column dimension (in mm) Beam dimension (in mm) 250 x x x x x x x x x x x x x x x x x x x x Code and Standards The code and standards for a loading and a structural evaluation which was used are below : SNI : Earthquake Resilience Planning Standard for Building Structure SNI : Standard of Design of Reinforced Concrete and Buildings Structures SNI : Standard of Design Steel Structure for Building Structures SNI : Standard of Loading Design for Housing and Buildings. ACI : Building Code Requirements for Structural Concrete and Commentary Hazard Map of the Indonesia Earthquake 2010 as the Basic of Planning and Design of Earthquake Resistant Infrastructures Material Quality The structural concrete quality data is obtained directly by a concrete hammer test. The concrete quality which is obtained from the hammer test is quite good. For beams and plates, the average concrete quality is f c = 22,5 MPa and a columns is f c ' = 30 MPa. The steel reinforcement quality is used are BJTP-24 (f y = 240 MPa) for plain bar and BJTD-39 (f y = 390 MPa) for deformed bar respectively. 3. DAMAGE EVALUATION OF EXISTING BUILDING Based on a direct field observation, the damage of building can be categorized to nonstructural and structural elements. Damages of non-structural element are a damage that occurs in the non-structural parts of buildings such as brick walls, ceilings, floor covering etc. The structural damages are a cracked or broken of structural elements building, such as columns, beams, plates and foundation editor@iaeme.com

Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail 3.1.

The damages are found in the form of cracks and collapse of the brick walls, ceiling and ceramic removal on the

Damage occurs in the form of a large crack until the collapse of some parts of the wall.

At the 2nd and 3rd floors the non-structural damage that occurs on the walls is only a fine crack up to medium

Figure 3 Typical non-structural damage of brick wall at the first floor of building.

Damage occurs in the form of frame ceiling damage that resulted ceiling detached.

The damage occurs due to the movement of structural elements such as beams and columns at the time of the

Figure 4 Damage of ceiling Figure 5 Damage of floor covering 3.2.

4 Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail 3.1. Non-structural Damages The most dominant non-structural damages were found at first floor of building. The damages are found in the form of cracks and collapse of the brick walls, ceiling and ceramic removal on the floor building. Damages of the brick wall occur almost in all parts of the wall building on the first floor. Damage occurs in the form of a large crack until the collapse of some parts of the wall. Some typical damage of brick walls that occurs in building can be seen in Figure 3. At the 2nd and 3rd floors the non-structural damage that occurs on the walls is only a fine crack up to medium crack at some parts of the wall. Figure 3 Typical non-structural damage of brick wall at the first floor of building. Damage of the ceiling occurs in several places. Damage occurs in the form of frame ceiling damage that resulted ceiling detached. At some point of the floor, damage occurred in the form of ceramic floor covering removal. The damage occurs due to the movement of structural elements such as beams and columns at the time of the earthquake. Figure 4 shows the damage of ceiling where the damage of floor covering is shown in Figure 5. Figure 4 Damage of ceiling Figure 5 Damage of floor covering 3.2. Structural Damage Structural damage are the damages that occurs in columns, beams, plates and stairs related to the strength of the building structure. Dominantly the structural damages occur on the first floor of the building. Damages of column structure are in the form of concrete failure and shear reinforcement release on the top column. Some location and forms of the damage of columns are shown in Figure 6. The main stair connecting the first to second floor was severely damaged as shown editor@iaeme.com

Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due to Earthquake in Figure 7.

damage, especially on the 1 st floor of the building. From direct field observation it can be identified possible cause of damage to buildings as follows: a.

Visually it can seen that the concrete on the 1 st floor column was damage in the area beam-column joint, but the concrete on the beam is not damaged. b. The hook of the shear reinforcement does not meet the standards.

Strong column weak beam mechanism is not implemented From the field observation and verification of as built drawing it is obtained data that the size a column is smaller than

5 Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due to Earthquake in Figure 7. This is due to the different structural behavior of stair with the behavior of overall building structure Figure 6 Column damage and released of shear reinforcement Figure 7 Damage of stair structure 4. EVALUATION OF CAUSES OF BUILDING DAMAGES Evaluation of the non-structural and structural damage occurs in the building it can be concluded that the building suffered severe damage, especially on the 1 st floor of the building. From direct field observation it can be identified possible cause of damage to buildings as follows: a. The beam-column joint is not monolith. This condition could be seen at all the damaged 1 st floor columns. Visually it can seen that the concrete on the 1 st floor column was damage in the area beam-column joint, but the concrete on the beam is not damaged. b. The hook of the shear reinforcement does not meet the standards. At damaged column it appears that the shear reinforcement split apart. This occurs due to hooks of stirrups do not meet standards c. Strong column weak beam mechanism is not implemented From the field observation and verification of as built drawing it is obtained data that the size a column is smaller than the size of a beam. This is tends the concrete damage occurs in the part of column only. 5. STRUCTURAL ANALYSIS 5.1. Structural Modeling and Loading Structural modeling is done in 3-dimensional form. Technical specifications structure for structural analysis is as follows: Building location Earthquake Region : Padang city Soil type: Soft soil Concrete quality : Jl. Khatib Sulaiman Padang : Padang editor@iaeme.com

Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail Column: K - 300 kg / cm 2 Beam: K - 225 kg / cm 2 Plates: K - 225 kg / cm 2 Reinforced Steel quality: BJTP-24 (f y =

Design of loading of dead load (DL) and live load (LL) based on SNI 03-1727-1989 Standard of Loading Design for Housing and Buildings.

U = 1,4 DL 2. U = 1,2 DL + 1,6 LL 3. U = 1.2 DL + 1,0 LL + 1,0 DNX1 + 0,3 DNY1 4. U = 1,2 DL + 1,0 LL + 1,0 DNX1 0,3 DNY2 5. U = 1.2 DL + 1,0 LL 1,0 DNX2 + 0.3 DNY1 6.

U = 1,2 DL + 1,0 LL 0,3 DNX2 + 1,0 DNY1 10.

6 Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail Column: K kg / cm 2 Beam: K kg / cm 2 Plates: K kg / cm 2 Reinforced Steel quality: BJTP-24 (f y = 240 MPa) for plain bar BJTD-39 (f y = 390 MPa) for deformed bar Figure 8 shows the structure modeling in 3-dimensional form. Design of loading of dead load (DL) and live load (LL) based on SNI Standard of Loading Design for Housing and Buildings. The design of earthquake load using the Hazard Map of the Indonesia Earthquake 2010 as shown in Figure 9. Structural analysis using ETABS program version The combination of loading taken is as follows: 1. U = 1,4 DL 2. U = 1,2 DL + 1,6 LL 3. U = 1.2 DL + 1,0 LL + 1,0 DNX1 + 0,3 DNY1 4. U = 1,2 DL + 1,0 LL + 1,0 DNX1 0,3 DNY2 5. U = 1.2 DL + 1,0 LL 1,0 DNX DNY1 6. U = 1,2 DL + 1,0 LL 1,0 DNX2 0,3 DNY2 7. U = 1,2 DL + 1,0 LL + 0,3 DNX1 + 1,0 DNY1 8. U = 1.2 DL + 1,0 LL + 0,3 DNX1 1,0 DNY2 9. U = 1,2 DL + 1,0 LL 0,3 DNX2 + 1,0 DNY1 10. U = 1,2 DL + 1,0 LL 0,3 DNX2 1,0 DNY2 Where: DL = dead load LL = live load DNX1 = earthquake load from right DNX2 = earthquake load from left DNY1 = earthquake load from front DNY2 = earthquake load from behind Figure 8 Building structural modeling Figure 9 Design of earthquake load for Padang city editor@iaeme.com

7 Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due to Earthquake 5.2. Capacity Analysis of Column Section Figure 10 and Figure 11 show the interaction diagram curves of axial force and bending moment (P-M) and plotting axial forces and bending moments obtained from structural analysis for column K1 at the first and second floors. From Figure 10 and 11 it can be seen that for the axial force (P) the column capacity is greater than the axial load, but for bending forces the column capacity is less than the bending load. This is evident from the presence of a number of bending loads located outside the interaction diagram curves, either on the first or second floor. Figure 10 Column interaction diagram of K1 at 1 st floor Figure 11 Column interaction diagram of K1 at 2 nd floor Tables 2 show the bending and shear capacity of all columns for every building floors. From the table it can be seen that the bending capacity of the columns on the first and second floors is insufficient, while for shear capacity is still sufficient. Table 2 Bending and shear capacity of all columns Column Dimension (mm) Bending capacity Shear capacity installed Necessary remarks K1 400x400 not Ok 165,66 kn 120,30 kn Ok K2 400x400 not Ok 165,66 kn 121,74 kn Ok K3 400x400 not Ok 165,66 kn 125,31 kn Ok K4 400x400 not Ok 165, 66 kn 130,63 kn Ok K5 400x400 not Ok kn 107,01 kn Ok K6 300x300 not Ok 165,66 kn 51,73 kn Ok K1 400x400 not Ok 165,66 kn 83,23 kn Ok K2 400x400 not Ok 165,66 kn 92,27 kn Ok K3 400x400 not Ok 165,66 kn 93,06 kn Ok K4 400x400 not Ok 165,66 kn 94,52 kn Ok K5 400x400 not Ok 165,66 kn 73,50 kn Ok K6 300x300 not Ok 102,88 kn 42,68 kn Ok K1 400x400 Ok 165,66 kn 42,72 kn Ok K3 400x400 Ok 165,66 kn 45,57 kn Ok K4 400x400 Ok 165,66 kn 54,09 kn Ok editor@iaeme.com

8 Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail K5 400x400 Ok 165,66 kn 36,27 kn Ok K6 300x300 Ok 102,88 kn 21,65 kn Ok 5.3. Capacity Analysis of Beam Section The actual bending and shear capacity of beam are summarized in Table 3. It can be seen that some of bending and shear capacity of beam section is insufficient. Table 3 Bending and shear capacity of beam No. 1 2 Beam (250/450) L = 4,800 mm (350/650) L = 7,200 mm Shear Bending Shear Bending Reinforcement position Max. capacity M n - / V n Internal forces M u - / V u Remarks Top support knm knm Ok Bottom support knm knm Not Ok Top centre knm knm Not Ok Bottom centre knm knm Ok Support kn kn Ok Centre kn kn Ok Top support knm knm Not Ok Bottom support knm knm Not Ok Top centre knm knm Ok Bottom centre knm knm Ok Support kn kn Ok Centre kn kn Not Ok 5.4. Bearing Capacity Analysis of Foundation The bearing capacity of building foundation is determined by comparing the permit bearing capacity of existing foundation to a total working load, with and without earthquake for every building column. The bearing capacity of the foundation (Q a ) is calculated by the Meyerh of formula (1956) using DCP (Dutch Cone Penetrometer) test results as follows : =0,025.. ; (1) = ; (2) Where: q c = value of DCP test (= 15,000 kpa. A p = area of foundation cross section D = diameter of foundation (= 1,50 m) Table 4 shows the axial load on each foundation point, with and without earthquake compared to bearing capacity of foundation. From Table 4 it can be seen that the bearing capacity of existing foundation is insufficient to support the design load editor@iaeme.com

9 Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due to Earthquake Point Table 4 Bearing capacity of foundation with and without earthquake load Axial load of column Total Total Allowable Remarks without with bearing DL LL Eqx Eqy earthquake earthquake capacity without with earthquake earthquake (tonf) (tonf) (tonf) (tonf) (tonf) (tonf) (tonf) Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok , Ok Not Ok , Ok Not Ok Not Ok Not Ok Not Ok Not Ok 15 69, Not Ok Not Ok Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Not Ok Ok Not Ok Ok Ok Ok Ok Max Not Ok Not Ok 6. CONCLUSION AND RECOMMENDATION 6.1. Conclusion From the results of the structural evaluation of BRI branch office building at Jl. Khatib Sulaiman Padang, it can be summarized as follows : 1. Non structural damage occurs at the walls, ceilings, and removal of floor tiles at several locations. 2. Structural damage occurs on the first floor, namely with heavily damaged conditions on column and stair structures editor@iaeme.com

10 Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail 3. In the implementation of the work of building structures found many implementation errors which occurs in the field, for instance the beam column joint are not monoliths, hooks reinforcement for shear do not meet a standard. 4. The concrete quality testing with hammer test is still quite good for concrete quality standard that is above K-225 kg / cm The bending capacity at the first and second floor columns insufficient compared to design bending capacity. 6. The bearing capacity of the existing foundation is not capable to support the building axial load. 7. Based on the above points, it is concluded that the building of BRI branch office at Khatib Sulaiman no. 50 Padang cannot more used and should be destroyed Recommendation Based on the conclusion, it is recommended that the damaged BRI branch office building at Jalan Khatib Sulaiman no. 50 Padang cannot more used and proposed to be destroyed. ACKNOWLEDGEMENTS The authors would like to thanks to the foundation of Dana Pensiun BRI Jakarta to perform the structural evaluation of damaged BRI Branch Office at Jalan Khatib Sulaiman no. 50 Padang. REFERENCES [1] Boen,T.,& Rekan, Cara Memperbaiki Bangunan Sederhana yang Rusak akibat Gempa Bumi Cetakan Kedua, 2010 [2] EERI Special Earthquake Report, Learning from Earthquakes, The Mw 7.6 Western Sumatra Earthquake of September 30, 2009, December [3] Fauzan, Zaidir and Laura M. P, Analisa kegagalan Struktur dan Perkuatan (Retrofitting) Kolom Gedung B SMA N 10 Padang yang rusak akibat Gempa 30 September 2009, Jurnal Teknika, ISSN: No. 34 vol 1, [4] Fauzan, Febrin Anas Ismail, Zaidir, Abdul Hakam, Nugrafindo Yanto, Rahmat Ramli., Identifikasi Kerusakan dan Metode Perkuatan Struktur Kantor Gubernur Sumatera Barat, Prosiding Seminar Nasional Teknik Sipil 1 (SeNaTS 1) Tahun 2015, Sanur - Bali, 25 April 2015, ISBN ,2015. [5] Fauzan, Analisis Metode Pelaksanaan Retrofitting pada Bangunan Sederhana (Studi Kasus: SD Negeri 43 Rawang Timur, Padang), Jurnal Rekayasa, Vol. 8 No. 1, ISSN: , [6] Febrin Anas Ismail, Abdul Hakam and Fauzan, Kerusakan Bangunan Hotel Bumi Minang Akibat Gempa 30 September 2009, Jurnal Teknik Sipil ITB, ISSN , Vol 10 no. 2 pp , 2011 [7] Febrin Anas I, et.al, Retrofitting of Bumiminang Hotel Building in Padang, The 6 th Civil Engineering Conference in Asia Region (CECAR6), Agust 2013, Jakarta [8] Paul Grundy, The Padang Earthquake 2009 Lessons and Recovery Australian Earthquake Engineering Society 2010 Conference, Perth, Western Australia, Department of Civil Engineering, Monash University. [9] Thermou, G. and Elnashai, A.S. (2002), Performance Parameters and Criteria for Assessment and Rehabilitation, Seismic Performance Evaluation and Retrofit of Structures (SPEAR), European Earthquake Engineering Research Network Report, Imperial College, UK editor@iaeme.com

11 Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due to Earthquake [10] Zaidir, Maizul N and Laura M.P, Evaluasi kelayakan bangunan bertingkat pasca gempa 30 September 2009 Sumatera Barat, Jurnal Rekayasa Sipil, Vol. 8 No. 1, pp.61-73, 2012 [11] Zaidir, Fauzan, Dina Angreini, Evaluasi Kelayakan Struktur Bangunan Gedung Ex. PO.ANS berdasarkan SNI Gempa 1726:2012, Prosiding 3 rd Andalas Civil Engineering National Conference, pp.75-89, ISBN ,2016 [12] Zaidir, Fauzan, Abdul Hakam, Febrin A Ismail dan Teddy Boen, Retrofitting Gedung Balaikota Padang dengan Menggunakan Kawat Anyam, Seminar Nasional Strategi Pengembangan Infrastruktur, Kampus ITP, Padang Agustus 2014, ISBN : [13] G. Tirupathi Naidu, Dr. Balaji. K.V.G.D, M. Pavan Kumar and L. Manikanta, A Study on Behaviour of Structural Elements of Berthing Structure with Raker Pile and Anchored Wall, International Journal of Civil Engineering and Technology, 8(7), 2017, pp [14] M. Balaji, K. Manikanda Prasath, S. Venkatesh and A.P. Arun, An Application of Interpretive Structural Modeling To Assess Agility Index, International Journal of Civil Engineering and Technology, 8(9), 2017, pp editor@iaeme.com

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