Article Per Year (5 Year)
p-Index From 2020 - 2025
2.162
P-Index
This Author published in this journals
All Journal Inersia : Jurnal Teknik Sipil dan Arsitektur MEDIA KOMUNIKASI TEKNIK SIPIL Jurnal Teknik Sipil Prosiding Forum Studi Transportasi Antar Perguruan Tinggi Jurnal Ilmiah Dinamika Rekayasa (DINAREK) Teras Jurnal Journal of the Civil Engineering Forum LANGKAU BETANG: JURNAL ARSITEKTUR Jurnal Aplikasi Teknik Sipil Jurnal Riset Rekayasa Sipil Journal of the Civil Engineering Forum
Bambang Suhendro
Departemen Teknik Sipil Dan Lingkungan, Universitas Gadjah Mada, Yogyakarta
Civil Engineering, Building, Construction & Architecture Control & Systems Engineering Electrical & Electronics Engineering Engineering Environmental Science Industrial & Manufacturing Engineering Transportation Other

Published : 15 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 15 Documents
Search

 1   2 
BEHAVIOR OF NAILED-SLAB SYSTEM ON SOFT CLAY DUE TO REPETITIVE LOADINGS BY CONDUCTING FULL SCALE TEST Puri, Anas; Hardiyatmo, Hary Christady; Suhendro, Bambang; Rifa'i, Ahmad
Prosiding Forum Studi Transportasi Antar Perguruan Tinggi Vol 2 No 1 (2015): Prosiding Forum Studi Transportasi antar Perguruan Tinggi
Publisher : FSTPT Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The Nailed-slab System is not a soil improvement method, but rather as an alternative method to improve the performance of rigid pavement on soft soils. The installed piles under the slab were functioned as slab stiffeners. This research is aimed to learn the behavior of Nailed-slab System under repetitive loadings and its consideration for practical application. The full scale Nailed-slab System was conducted on soft clay which consisted of 6.00 m x 3.54 m slab area with 0.15 m in slab thickness, 15 short micro piles (0.20 m in diameter, 1.50 m in length, and 1.20 m in pile spacing) as slab stiffeners which installed under slab. Piles and slab were connected monolithically, then in due with vertical concrete wall barrier on the two ends of slab. The system was loaded by vertical repetitive loadings. Results show that the installed piles under the slab which embedded into the soils were functioned as slab stiffeners and were able to response similarly in 3D. This system has higher resistance due to vibration. Thereby, the Nailed-slab system is promising for practical application.
Analisis Perubahan Tekanan Air Pori pada Tanah Lunak akibat Beban Trial Embankmentdengan menggunakan Plaxis Versi 7.2. Patria, Adhe Noor; Suryolelono, Kabul Basah; Suhendro, Bambang
Dinamika Rekayasa Vol 5, No 1 (2009): Dinamika Rekayasa - Februari 2009
Publisher : Jenderal Soedirman University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20884/1.dr.2009.5.1.16

Abstract

Soft soil could be found easily in Indonesia. Constructions that built on this soil; such as embankment; face some obstructions, for instance long period consolidation, difficult soil compaction, unstable slope of embankment and high settlement value for long period. Consolidation related to particle size of soil grains, soil permeability coefficient and pore size between soil particles. This research was carried out with numerical simulation and aimed to analyze the change in pore water pressures in soft soil due to embankment load.Numerical simulation was carried out by using Plaxis version 7.2. The time periods for construction and consolidation were the same with field measurement values. Total times for both stages were 102 days. Material model used were Mohr Coulomb Model and input material model that were used were the same with filed measurement values.The results showed that at the end of construction stage there always an increasement in pore water pressure (excess pore water pressure existed) and the decreasement of pore water pressure occurred in consolidation period. Excess pore water pressures of soil below embankment were at area A, depth 0,5 was -22,8093 kPa, at area B (depth 9 m) was -21,5576 kPa and at area C (depth 13 m) was -14,159 kPa.
NON-LINEAR ANALYSIS OF HOLLOW REINFORCED CONCRETE COLUMN QUARE CROSS-SECTION WITH VARIOUS LOAD ECCENTRICITY AND CONCRETE STRENGTH Nuryanti, Pingkan; Sulityo, Djoko; Suhendro, Bambang
LANGKAU BETANG: JURNAL ARSITEKTUR Vol 5, No 1 (2018): June
Publisher : Department of Architecture, Universitas Tanjungpura

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (459.931 KB) | DOI: 10.26418/lantang.v5i1.24083

Abstract

Hollow due to plumbing system has an effect to the building's visual and the aesthetic quality in terms of architecture. To overcome this, the pipe is planted in a construction structure such as a column. However, this will affect on the strength degradation and modes of failure of structural elements such as a column. The objective of this research is to study the strength, stiffness, ductility, cracking patterns, and modes of failure of hollow RC columns with square cross-section with various load eccentricity and concrete strength. In this research, 13 reinforced concrete columns with square cross section were made. Two of them were massive columns (C1E1, C1E2) with cross-sectional dimension of 150 x 150 mm2 and 800 mm long, six of them were hollow with the same size (C2E1, C3E1, C4E1, C2E2, C3E2, C4E2). Concrete strength fc'=34.52 MPa with eccentricity=60mm  and fc'=35.72 MPa with eccentricity 100 mm. Models were analyzed by nonlinear finite element method using ATENA v.2.1.10 software. The FE model is calibrated against recent experimental results from Zacoeb (2003). Once validated, the model is used to examine stiffness, ductility, cracking patterns, and modes of failure of hollow RC columns with a square cross-section with various load eccentricity. The numerical results show that the different ultimate load strength of C1E1, C2E1, C3E1, C4E1, C1E2, C2E2, C3E2, C4E2 are  0,32%, 2,22%, 1,61%, 7,74%, 1,25%, 0,65%, 2,63%, 1,94%, while the differents stiffnes are 18,30%, 21,30%, 23,79%, 31,57%, 15,22%, 22,67%, 21,39%, 14,41%, and the differents ductility are 48,71%, 33,64%, 3,39%, 41,04%, 52,30%, 22,99%, 18,11%, 7,76%. Crack pattern occurred in C1E1, C2E1, C3E1, C4E1, C1E2, C2E2, C3E2, C4E2 are flexural crack and shear cracks. Exhibit modes of failure of C1E1, C2E1, C3E1, C4E1 are compression failure and C1E2, C2E2, C3E2, C4E2 are tension failure.Keywords: ATENA, columns, eccentricity, failure, hollow, nonlinearANALISIS NON-LINEAR KOLOM BETON BERTULANG PENAMPANG SEGIEMPAT BERONGGA DENGAN VARIASI EKSENTRISITAS BEBAN DAN MUTU BETONLubang akibat pemasangan pipa pada konstruksi untuk keperluan instalasi (air hujan, sanitasi, listrik dan lain-lain) dapat berpengaruh pada visualitas bangunan dan akan mempengaruhi kualitas estetika dari segi arsitektur. Untuk mengatasi hal tersebut pipa ditanam didalam struktur konstruksi seperti kolom. Akan tetapi hal ini akan  menyebabkan  degradasi kekuatan beton dan  pola keruntuhan struktur pada kolom. Selain secara eksperimental, penelitian  ini dapat juga dilakukan secara numeris menggunakan  metode elemen hingga nonlinier. Penelitian ini bertujuan untuk mengetahui kekuatan, kekakuan, daktilitas, pola retak dan model keruntuhan kolom beton bertulang penampang persegi berongga dengan variasi eksentrisitas beban dan variasi mutu beton. Dalam penelitian ini dimodelkan 8 jenis kolom beton bertulang penampang segiempat yang terdiri dari 2 kolom masif (C1E1 dan C1E2) dan 6 kolom berongga (C2E1, C3E1, C4E1, C2E2, C3E2, C4E2) dengan ukuran 150 x 150 mm2, panjang 800 mm. Mutu beton fc'=34.52 MPa dengan eksentrisitas =60mm dan mtu beton fc'=35.72 MPa dengan eksentrisitas =100mm. Kolom dianalisis menggunakan software elemen hingga nonlinier ATENA V.2.1.10 dan hasilnya dibandingkan dengan hasil eksperimen sebelumnya  dari Zacoeb (2003). Setelah  model divalidasi, dilakukan perhitungan kekakuan, daktilitas, pengamatan pola retak dan jenis keruntuhan yang terjadi pada kolom penampang segiempat berongga dengan variasi eksentrisitas beban . Hasil penelitian menunjukkan bahwa kolom beton bertulang  berongga yang dimodelkan dengan ATENA yaitu untuk model kolom validasi C1E1, C2E1, C3E1, C4E1, C1E2, C2E2, C3E2, C4E2 mempunyai perbedaan beban maksimum dengan hasil eksperimen secara berturut-turut sebesar 0,32%, 2,22%, 1,61%, 7,74%, 1,25%, 0,65%, 2,63% dan 1,94%, dengan perbedaan kekakuan secara berturut-turut sebesar 18,30%, 21,30%, 23,79%, 31,57%, 15,22%, 22,67%, 21,39% dan 14,41%, dan perbedaan daktilitas  secara berturut-turut sebesar 48,71%, 33,64%, 3,39%, 41,04%, 52,30%, 22,99%, 18,11% dan 7,76%. Pola retak yang terjadi adalah pola retak lentur dan retak geser.  Pola keruntuhan pada C1E1, C2E1, C3E1, C4E1 merupakan keruntuhan tekan, sedangkan C1E2, C2E2, C3E2, C4E2  merupakan keruntuhan tarik.Kata-Kata kunci: ATENA, berlubang, eksentrisitas, keruntuhan, kolom, nonlinear.REFERENCESCervenka et al. (2007). Superior Material Models for Numerical Simulation of Concrete Cracking under Severe Conditions. Cervenka Consulting. Czech Republic.Public Work Ministry. (2007). SNI 03-2847-2007, Tata Cara Perhitungan Struktur Beton Bertulang untuk Bangunan Gedung. Bandung.Poston et al. (1985). Numerical Models for Non-prismatic Solid Cross-Section Behavior and Rectangular Cross-Section on Biaxially-Bred ColumnsSuprabowo, S. (1996). Analysis of Reinforced Concrete Column Capacity Perforated. Thesis. Department of Civil Engineering, Gadjah Mada University. Yogyakarta.Supriyadi. (1997). The Effect of Holes on Strongly Reinforced Concrete Column Boundaries. Thesis. Graduate Program. Gadjah Mada University. Yogyakarta.Zacoeb. A. (2003). Flexural Capacity of Reinforced Concrete Short Column with Variations Hole, Thesis. Graduate Program. Gadjah Mada University. Yogyakarta.
Perilaku Rangka Open Web Truss Joist LVL Sengon Basuki, Achmad; Awaludin, Ali; Suhendro, Bambang; Siswosukarto, Suprapto
MEDIA KOMUNIKASI TEKNIK SIPIL Volume 27, Nomor 1, JULI 2021
Publisher : Department of Civil Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (141.817 KB) | DOI: 10.14710/mkts.v27i1.31916

Abstract

Laminated Veneer Lumber (LVL) Sengon is classified as one of the engineering products having a significant increase of both physical and mechanical properties compared with Sengon solid wood. Considering its short planting years and sustainable production, Sengon wood is very potential to be used as construction materials of low-rise houses to support the housing needs in Indonesia. Creep behaviour of LVL Sengon material is one of the mechanical properties that needs to be considered. This article evaluated value of creep factor of the open web truss joist (OWTJ) LVL Sengon test and compared this experimental creep factor with the numerical results developed by FE model taking into account the viscoelastic parameters of authors' previous study. The viscoelastic parameters were based on a 217-day creep test of compression and tension parallel to the grain of LVL Sengon at 20 % of stress level that were further modeled using Prony series creep model having n equals to 3. The reduction in the modulus of elasticity over time resulted in creep deflection and creep factor values at 217 days of testing results and FE numerical analysis of the OWTJ LVL Sengon ranging from 1.50–1.54; while the predicted creep factor at 25 years of service life is 1.57 or greater than the creep factor value provided in SNI 7973: 2013 of 1.5.
STUDI EXPERIMENTAL BALOK SLOOF-KOLOM PADA RUMAH INSTAN STRUKTUR BAJA DENGAN METODE PEMBEBANAN SIKLIK Heribertus Sigit Kianjaya; Iman Satyarno; Bambang Suhendro
Jurnal Teknik Sipil Vol. 16 No. 3 (2021)
Publisher : Program Studi Teknik Sipil Fakultas Teknik Universitas Atma Jaya Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (831.151 KB) | DOI: 10.24002/jts.v16i3.5388

Abstract

Rumah Instan Struktur Baja (RISBA), merupakan model bangunan yang dapat digunakan dalam rekonstruksi perumahan masyarakat yang rusak dilanda gempa di Lombok. Rumah RISBA dipilih karena dari segi bahan yang relatif mudah ditemukan dan terbuat dari bahan ringan, dari segi biaya relatif lebih murah dan dan dari segi waktu konstruksi relatif lebih cepat dibandingkan jenis bangunan lain yang terbuat dari beton. Untuk menentukan resistensi kolom rumah RISBA, studi eksperimental dilakukan pada perilaku siklik kolom (mewakili setengah dari tinggi kolom aktual) 1500 mm yang di sendi pada balok sloof sepanjang 750 mm. Tes siklik dilakukan berdasarkan metode ASTM-E2126. Bahan baja memiliki proerties berikut: fy = 268.104 MPa , dan fu = 331.311 MPa, sedangkan kekuatan kompresi mortar yang digunakan adalah fc' = 9.122 MPa. Loop histeresis yang dihasilkan dan kurva amplop untuk spesimen SB-1 adalah : (a) Ppeak (+) adalah 5,01 kN pada perpindahan 84 mm dengan rasio drift 5,6%, (b) Ppeak (-) adalah 4,93 kN pada perpindahan 84 mm dengan rasio drift 5,6%. Selisih antara SB-1 dan SB-2 pada Ppeak (+) adalah 0,02 kN, sedangkan Ppeak (-) adalah 0,2 kN. Jenis kegagalan pada spesimen SB- 1 adalah dalam bentuk buckling lokal pada kolom, dan kegagalan kompresi pada balok sloof, sementara jenis kegagalan pada spesimen SB-2 adalah dalam bentuk kompresi pada balok sloof tetapi tidak ada kegagalan buckling pada kolom.
Bridge Displacement Estimation using Tiltmeter Data Raka Bagus Panuntun; Akhmad Aminullah; Bambang Suhendro; Panji Krisna Wardana
Journal of the Civil Engineering Forum Vol. 5 No. 2 (May 2019)
Publisher : Department of Civil and Environmental Engineering, Faculty of Engineering, UGM

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1325.971 KB) | DOI: 10.22146/jcef.43670

Abstract

Structural Health Monitoring System (SHMS) works as an efficient platform for monitoring health condition and and deterioration of civil structures during long-term service periods. One of the sensors is currently applied to Soekarno Bridge is tiltmeter. Vertical displacement data are often required to reflect the overall response of bridge span, however the Soekarno Bridge does not have any displacement sensor. On the other hand, the displacement sensor is very costly compared to tiltmeter. A method is proposed to estimate bridge displacement using data that is collected through tiltmeter. The method is using interpolation and numerical integration to evaluate the displacement. The result shows that the result obtained from the proposed method is reliable with accuracy of displacement around 5 mm. Some recommendations for further implementation of the sensors are provided.
Airfield Asphalt Overlay Design for Non-conventional Pavement Structures: A Case Study of Airport in Indonesia Taqia Rahman; Bambang Suhendro; Wardhani Sartono; Purbolaras Nawangalam; Hary Christady Hardiyatmo
Journal of the Civil Engineering Forum Vol. 8 No. 2 (May 2022)
Publisher : Department of Civil and Environmental Engineering, Faculty of Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2179.45 KB) | DOI: 10.22146/jcef.3771

Abstract

Airfield pavements begin a gradual deterioration from several sources, including traffic load and environmental conditions. To achieve its intended design life, routine maintenance, repair, and rehabilitation should be performed. There are considerable research and studies conducted on the design and practice of pavements rehabilitation/overlay for typical airfield pavements. However, most of the existing guidelines and studies are only suitable for pavements with conventional structures. There has been no detailed investigation into the practice of airfield asphalt overlay for non-conventional pavement structures, such as chicken claw /Cakar Ayam pavement system and nailed-slab system. In the present article, challenges and issues for airfield asphalt overlay design for non-conventional pavement structures were examined based on an actual runway rehabilitation project in one of the major airports in Indonesia in 2015. The overlay design procedure, the evaluation of the existing pavement condition, including visual surveys and deflection tests, and the pre-overlay treatments were also discussed. In addition, a finite element (FE) simulation to model the non-conventional pavement structure was developed to calculate the required overlay thickness. The result showed that, during the overlay design of non-conventional pavement structure, data from falling weight deflectometer (FWD) could not be directly used to estimate the back-calculated layers moduli because of the difference in the geometric features of the pavement structure. Moreover, the FE model can be a robust tool to simulate the complex three-dimensional geometric features of a non-conventional pavement and important loading conditions, such as interface shear bond of overlay, that are usually not available in other tools, such as FAARFIELD. Finally, this study showed that the additional asphalt overlay could reduce the fatigue stress at the bottom of the existing slab and vertical stress at the top of the subgrade, resulting in overall smaller stress levels
EVALUASI SEISMIK GEDUNG BERTINGKAT EKSISTING MENGGUNAKAN PROSEDUR ASCE 41-17 Yuliar Azmi Adhitama; Bambang Supriyadi; Bambang Suhendro
Jurnal Riset Rekayasa Sipil Vol 6, No 1 (2022): September 2022
Publisher : Civil Engineering Study Program, Engineering Faculty Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (994.022 KB) | DOI: 10.20961/jrrs.v6i1.65864

Abstract

Gedung XYZ merupakan gedung beton bertulang 5 lantai dengan proses perencanaan ketahanan gempa gedung menggunakan standar SNI 1726:2002, sedangkan saat ini berlaku standar perencanaan ketahanan gempa yang baru mengacu pada SNI 1726:2019. Perubahan peta gempa dan cara perancangan spektra desain menjadikan proses evaluasi ketahanan gempa menjadi menarik untuk diteliti sehingga dapat mengetahui kinerja struktur bangunan. ASCE 41-17 adalah standar yang diterbitkan oleh American Society of Civil Engineers mengatur evaluasi seismik dan evaluasi perbaikan bangunan eksisiting. Proses evaluasi berdasarkan data sekunder asbuilt drawing yang dianalisis menggunakan prosedur statik nonlinier (pushover) dengan program SAP2000. Hasil analisis struktur ditinjau secara global, Gedung XYZ mampu menahan gaya lateral sampai pada displacement target dan memenuhi target kinerja Immediate Occupancy untuk seismic hazard BSE-1E dan target kinerja Life Safety untuk seismic hazard BSE-2E. Distribusi sendi plastis terjadi pada balok terlebih dahulu, sehingga memenuhi prinsip strong column weak beam. Namun jika dilihat lebih detail, balok G2 tidak memenuhi persyaratan ketika dievaluasi menggunakan metode statik nonlinier dengan koefisien gc (DCR 1,14) dan jika tidak dikalikan koefisien gc balok tersebut masih memenuhi syarat dengan (DCR 0,91). Kapasitas kolom dalam menerima demand secara keseluruhan memenuhi syarat dengan rasio kurang dari 1. Setiap jenis kolom memenuhi syarat baik ketika demand tidak dikalikan dengan koefisien gc maupun setelah dikalikan dengan koefisien gc.
Dynamic Properties Comparison of 1D, 2D, and 3D Model for Concrete Box-Girder Bridge of 40-meter Span Wira Sucitra Ibrahim; Akhmad Aminullah; Ali Awaludin; Bambang Suhendro; Bambang Supriyadi; Renga Rao Krishnamoorthy
Journal of the Civil Engineering Forum Vol. 8 No. 3 (September 2022)
Publisher : Department of Civil and Environmental Engineering, Faculty of Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jcef.4148

Abstract

Concrete box-girder structure is considered the thin-walled structure, undergoing deformation and forces, as well as having structural rigidity in three dimensional directions. However, it’s commonly modeled as 1D structure for the sake of design practicality, which influences the numerical result of its dynamic properties when compared to both real time SHMS and field test result. To see how far the difference of the dynamic properties between 1D, 2D, and 3D model of concrete box-girder structure, the concrete box-girder structure is modeled as 1D (frame), 2D (shell), and 3D (solid) element with MIDAS Civil 2019. Considering the allowable deflection and stress limited by design code, concrete box-girder structure is modeled and analyzed as linearly elastic material. The dynamic properties obtained from these 3 models were compared with those obtained from real time SHMS and field test. These results indicate that both natural frequency and period of 2D and 3D models are close to those of real time SHMS and field test. However, the natural frequency of 1D model is slightly larger than the real SHMS and field test, indicating that 1D model gives the slightly overestimate natural frequency and structural rigidity compared to the reality. Unlike 2D and 3D model, the structure is accounted to have the uniform sectional rigidity along transversal direction in 1D model. This is why 1D model seems to have higher structural rigidity compared to 2D and 3D model, which subsequently yields the higher natural frequency than 2D and 3D model. This research proves that the designers’ discretion is advised if 1D model is used for the sake of design practicality.
Effect of Creep on The Long-Term Deflection of Box Girder Balanced Cantilever Bridge Structure Using B3 Model and CEB 2010 Luki Hariando Purba; Bambang Supriyadi; Bambang Suhendro
Journal of the Civil Engineering Forum Vol. 9 No. 1 (January 2023)
Publisher : Department of Civil and Environmental Engineering, Faculty of Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jcef.4905

Abstract

Creep significantly affects the long-term deflection of the prestressed concrete bridge structure. Some models often used in predicting creep do not consider the water-cement ratio. The water-cement ratio is a factor in the magnitude of creep. If the water-cement ratio is excessive, the creep will also be significant. B3 Model uses the water-cement ratio in predicting creep in prestressed concrete bridge structures and has provided good accuracy with measured deflection data. This study compares B3 Model with Model CEB 2010 to predict the effect of creep on the long-term deflection. The author modeled the bridge structure using Midas Civil 2022 v1.2 software by utilizing the construction stages analysis facility to idealize the balanced cantilever and the effect of creep on the long-term deflection. Envelope displacement of bridge B3 Model is more significant than CEB 2010. The prediction deflection of the B3 Model in 100 years of service life of the bridge is -16.34 cm, while CEB 2010 is -11.90 cm. Creep affects total deflection by 84% to 88%. Creep affects the deflection significant because, in the construction process, each box girder segment is stressed and loaded at the age of 3 days. At the age of 3 days, the elastic modulus of the concrete is still not entirely, and the cement paste on the concrete is still in the hydration process. The results showed a significant difference between B3 Model and CEB 2010. B3 Model predicts that the long-term deflection of the bridge until the end of the bridge's service life is 44% to 49% greater than the CEB 2010 model. Prediction of total deflection until the end of 100 years of bridge service life does not exceed the limit determined by SNI and CEB codes.
Co-Authors Achmad Basuki Ade Trias Safrudin Adhe Noor Patria, Adhe Noor Aisyah Aisyah Akhmad Aminullah Ali Awaludin Ali Awaludin Aminnullah, Akhmad Aminullah, Akhmad Anas Puri, Anas Anno Mahfuda Bambang Supriyadi Hary Christady H. Hary Christady Hardiyatmo, Hary Christady Heribertus Sigit Kianjaya Iman Satyarno Kabul Basah Suryolelono Luki Hariando Purba Nasution, Multilawati Nuryanti, Pingkan Panji Krisna Wardana Purbolaras Nawangalam Raka Bagus Panuntun Renga Rao Krishnamoorthy Rini Kusumawardani, Rini Sulityo, Djoko Suprapto Siswosukarto Suprapto Siswosukarto Taqia Rahman Vallentino, Rizky Veithzal Rivai Zainal Wardhani Sartono Wira Sucitra Ibrahim Yuliar Azmi Adhitama