OLEH Dr Eng I MADE GATOT KAROHIKA ST

OLEH: Dr. Eng. I MADE GATOT KAROHIKA, ST. MT JURUSAN TEKNIK MESIN FT – UNUD, SEMESTER GENAP 2017 -2018

Apa itu Mekanika? Mekanika adalah ilmu yang menggambarkan dan meramalkan kondisi benda yang diam atau bergerak karena pengaruh gaya yang beraksi pada benda. Mechanics Rigid Bodies (Things that do not change shape) Statics Dynamics Deformable Bodies (Things that do change shape) Fluids Incompressible Compressible

Buku apa yang dipakai? • F. P. Beer and E. R. Johnston Jr. , Vector Mechanics for Engineers: Statics, SI Metric Edition, Mcgraw-hill, atau • F. P. Beer and E. R. Johnston Jr. , Mekanika Untuk Insinyur : STATIKA [TERJEMAHAN; VERSI INDONESIA] • J. L Meriem, dkk, Engineering Mechanics, Statics, John Wiley & Sons. Inc. • J. L Meriem, dkk, MEKANIKA TEKNIK; STATIKA [indonesia] • R. C. Hibbeler, Engineering Mechanics, 7 th - 12 th Edition, Person Prentice-Hall • Dll • Pinjam buku ruang baca

Bagaimana evaluasinya ? • • • TUGAS : 20 % Quis : 20 % [open book] UTS : 30 % (sifat: closed book) UAS : 30 % (sifat: …………. ) Absensi >= 75% : (Maksimal ketidak hadiran dengan/tanpa alasan 3 kali). • TIDAK ADA UJIAN SUSULAN!!!

Apa saja yang dipelajari? I. INTRODUCTION What is Mechanics? Fundamental Concepts Fundamental Principles Systems of Units Method of Problem Solution Numerical Accuracy

2. STATICS OF PARTICLES Introduction Resultant of Two Forces Vectors Addition of Vectors Resultant of Several Concurrent Forces Sample Problem 2. 1 Sample Problem 2. 2 Rectangular Components of a Force: Unit Vectors Addition of Forces by Summing Components 2 -6 Sample Problem 2. 3 Equilibrium of a Particle Free-Body Diagrams Sample Problem 2. 4 Sample Problem 2. 6 Rectangular Components in Space Sample Problem 2. 7

3. RIGID BODIES: EQUIVALENT SYSTEM OF FORCE Introduction Moment of a Force About a Given Axis External and Internal Forces Sample Problem 3. 5 Principle of Transmissibility: Equivalent Moment of a Couple Forces Addition of Couples Vector Products of Two Vectors Couples Can Be Represented By Vectors Moment of a Force About a Point Varigon’s Theorem Rectangular Components of the Moment of a Force Resolution of a Force Into a Force at O and a Couple Sample Problem 3. 6 Sample Problem 3. 1 System of Forces: Reduction to a Force and a Couple Scalar Product of Two Vectors Further Reduction of a System of Forces Scalar Product of Two Vectors: Applications Sample Problem 3. 8 Mixed Triple Product of Three Vectors 3 -7 Sample Problem 3. 10

4. Equilibrium of Rigid Bodies Introduction Free-Body Diagram Reactions at Supports and Connections for a Two. Dimensional Structure Equilibrium of a Rigid Body in Two Dimensions Statically Indeterminate Reactions Sample Problem 4. 1 Sample Problem 4. 3 Sample Problem 4. 4 Equilibrium of a Two-Force Body Equilibrium of a Three-Force Body Sample Problem 4. 6 4 -8 Equilibrium of a Rigid Body in Three Dimensions Reactions at Supports and Connections for a Three-Dimensional Structure Sample Problem 4. 8

5. Distributed Forces: Centroids and Centers of Gravity Introduction Theorems of Pappus-Guldinus Center of Gravity of a 2 D Body Sample Problem 5. 7 Centroids and First Moments of Areas and Lines Distributed Loads on Beams Centroids of Common Shapes of Areas Centroids of Common Shapes of Lines Center of Gravity of a 3 D Body: Centroid of a Volume Composite Plates and Areas Centroids of Common 3 D Shapes Sample Problem 5. 1 Composite 3 D Bodies Determination of Centroids by Integration Sample Problem 5. 12 Sample Problem 5. 4 5 -9 Sample Problem 5. 9

6. Analysis of Structures Introduction Definition of a Truss Simple Trusses Analysis of Trusses by the Method of Joints Under Special Loading Conditions Space Trusses Sample Problem 6. 1 Analysis of Trusses by the Method of Sections 6 - 10 Trusses Made of Several Simple Trusses Sample Problem 6. 3 Analysis of Frames Which Cease to be Rigid When Detached From Their Supports Sample Problem 6. 4 Machines

7. Forces in Beams and Cables Introduction Sample Problem 7. 4 Internal Forces in Members Sample Problem 7. 1 Various Types of Beam Loading and Support Shear and Bending Moment in a Beam Sample Problem 7. 2 Sample Problem 7. 3 Relations Among Load, Shear, and Bending Moment 7 - 11 Sample Problem 7. 6 Cables With Concentrated Loads Cables With Distributed Loads Parabolic Cable Sample Problem 7. 8 Catenary

8. FRICTION Introduction Square-Threaded Screws Laws of Dry Friction. Coefficients of Friction. Sample Problem 8. 5 Angles of Friction Problems Involving Dry Friction Sample Problem 8. 1 Sample Problem 8. 3 Wedges 8 - 12 Journal Bearings. Axle Friction. Thrust Bearings. Disk Friction. Wheel Friction. Rolling Resistance. Sample Problem 8. 6 Belt Friction. Sample Problem 8. 8

9. Distributed Forces: Moments of Inertia Introduction Moments of Inertia of an Area Moment of Inertia of an Area by Integration Polar Moment of Inertia Radius of Gyration of an Area Sample Problem 9. 1 Sample Problem 9. 2 Parallel Axis Theorem Moments of Inertia of Composite Areas Sample Problem 9. 4 Sample Problem 9. 5 Product of Inertia Principal Axes and Principal Moments of Inertia 9 - 13 Sample Problem 9. 6 Sample Problem 9. 7 Mohr’s Circle for Moments and Products of Inertia Sample Problem 9. 8 Moment of Inertia of a Mass Parallel Axis Theorem Moment of Inertia of Thin Plates Moment of Inertia of a 3 D Body by Integration Moment of Inertia of Common Geometric Shapes Sample Problem 9. 12 Moment of Inertia With Respect to an Arbitrary Axis Ellipsoid of Inertia. Principle Axes of Inertia of a Mass

10. Method of Virtual Work Introduction Work of a Force Work of a Couple Principle of Virtual Work Applications of the Principle of Virtual Work Real Machines. Mechanical Efficiency Sample Problem 10. 1 Sample Problem 10. 2 Sample Problem 10. 3 Work of a Force During a Finite Displacement Potential Energy and Equilibrium Stability and Equilibrium Sample Problems 10. 4 10 - 14

Apa yang harus dilakukan supaya Statika Struktur menjadi mudah ? Pahami konsepnya dan sering latihan soal-soal Prosedur mengerjakan soal: 1. 2. 3. 4. Baca soal dengan cermat Buat free body diagram dan tabulasikan data soal Tuliskan prinsip dasar / persamaan yang relevan dengan soal Selesaikan persamaan sepraktis mungkin sehingga didapat hasil yang signifikan dan jangan lupa disertai sistem satuan 5. Pelajari jawaban dengan akal sehat, masuk akal atau tidak 6. Jika ada waktu, coba pikirkan cara lain untuk menyelesaikan soal tersebut.