OLEH: FITRI HARDIYANTI MOCHAMAD YUSUF SANTOSO

Presentasi berjudul: "OLEH: FITRI HARDIYANTI MOCHAMAD YUSUF SANTOSO"— Transcript presentasi:

1 OLEH: FITRI HARDIYANTI MOCHAMAD YUSUF SANTOSO
KONSEP TEGANGAN OLEH: FITRI HARDIYANTI MOCHAMAD YUSUF SANTOSO

2 Can the structure safely support the 30 kN load?
Perform a static analysis to determine the internal force in each structural member and the reaction forces at the supports

3 Apakah cukup dengan statika saja ?
Ternyata gaya Internal pada tiap bagian belum dapat menentukan sebuah struktur aman atau tidak. Kenapa? Apa parameter untuk dikatakan aman/ kuat atau tidak?

4 Apa yang terjadi pada benda yang dikenai gaya ?

5 Loads Stresses Equilibrium Equations Displacements Strains Strain-Displacement Equations Load-Deflection or Load-Stress Relations Stress-Strain

6 Apa stress (tegangan) itu. Apakah macamnya hanya satu saja
Apa stress (tegangan) itu? Apakah macamnya hanya satu saja? Apakah hanya ada satu jenis beban (load) saja yang dapat menyebabkan stress ?

7 Untuk itu mari kita lihat secara umum gaya internal pada sebuah benda yang dikenai beberapa gaya eksternal

8 Internal Reactions Internal reactions are necessary to hold body together under loading. Method of sections - make a cut through body to find internal reactions at the point of the cut. Sambil lihat juga e-learning nya….

9 FBD After Cut Separate the two parts and draw a FBD of either side
Use equations of equilibrium to relate the external loading to the internal reactions.

10 Definisi Tegangan Tegangan : Intensitas gaya internal pada sebuah bidang spesifik

11 Macam-Macam Tegangan

12 Coplanar Force System Start with internal system of forces as shown below to get proper signs for V, N and M. V

13 Sample Problem SOLUTION:
Taking entire beam as free-body, calculate reactions at A and B. Determine equivalent internal force-couple systems at sections cut within segments AC, CD, and DB. Draw the shear and bending moment diagrams for the beam AB. The distributed load of 7200 N/m. extends over 0.3 m of the beam, from A to C, and the 1800 N load is applied at E. Plot results.

14 Sample Problem SOLUTION:
Taking entire beam as a free-body, calculate reactions at A and B. Note: The 1800 N load at E may be replaced by a 1800 N force and 180 Nm. couple at D.

15 Sample Problem Evaluate equivalent internal force-couple systems at sections cut within segments AC, CD, and DB. From A to C: From C to D:

16 Sample Problem Evaluate equivalent internal force-couple systems at sections cut within segments AC, CD, and DB. From D to B:

17 Sample Problem Plot results. From A to C: From C to D: From D to B:

18 Definisi Tegangan Normal
Tegangan normal adalah : Intensitas gaya internal yang bekerja tegak lurus terhadap bidang irisan Dimana : Tegangan normal Gaya yang bekerja tegak lurus terhadap irisan Luasan irisan

19 Tegangan Normal Rata-Rata
b. Internal Force a. External Force c. Stress

20 Kenapa kok disebut tegangan normal rata-rata ?
Figure: 01-13c

21 Jenis Tegangan Normal Figure: 01-15

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26 Terima Kasih