Primary burden of the bridge include dead loads, live loads and shock loads.
1. Dead load
Dead load is all cargo originating from its own weight of the bridge or bridge sections are reviewed, including any additional element is fixed that is considered one unit with a bridge. In determining the dead load weight of the volume should be used for building materials.
examples of dead load on the bridge: the weight of concrete, asphalt weight, the weight of steel, heavy masonry, stucco, etc. weight.
2. Living Expenses
Which includes the live load is the load that comes from moving vehicles, heavy traffic and / or pedestrians who considered working on the bridge. Based PPPJJR-1987, pages 5-7, the burden of living under review consists of:
a. Expenses "T" (Burden floor vehicles)
Expenses "T" is a load trucks that have a dual wheel load (Load Dual Wheel) by 10 tons, which works on the entire width of the bridge for vehicular traffic dingunakan.
b. Load "D" (Line traffic)
Load "D" is the arrangement of the load on each lane of traffic which consists of the load line "P" tons per lane of traffic (P = 12 tons) and the load evenly split "q" tons per meter length per lane as follows:
q = 2.2 t / m for L <30 m.
q = 2.2 t / m - {(1,1 / 60) x (L - 30)} t / m to 30 m
q = 1.1 {1 + (30 / L)} for L> 60 m.
Terms of use load "D" in the transverse direction of the bridge as follows:
§ To bridge the width of the vehicle floor <5.50 m, the burden of "D" is fully (100%) should be charged on the entire bridge.
§ To bridge the width of the vehicle floor> 5.50 m, the burden of "D" is fully (100%) charged to the line width of 5.50 m while the width of the remaining encumbered only half load "D" (50%).
examples of live load on the bridge: the burden of passing vehicles, loads of people walking, etc.
3. Shock load
According to Anonymous (1987:10) shock loads into account the influence of the vibrations of other dynamic effects., Stresses due to the load line (P) must be multiplied by the coefficient of shock. While the load evenly split (q) and the concentrated load (T) is multiplied by the coefficient of shock. The amount of shock coefficient is determined by the formula:
k = 1 + ((20 / (50 + L))
While the Secondary Expenses consist of wind load, brake force, and force due to temperature differences.
1. Wind load
Effect of pressure of work in the horizontal wind at 100 kg/cm2. In calculating the total area of the bridge on each side of the vast number of parts used jembata on each side used the following provisions:
* For a full walled jmbatan taken as 100% on the broad side of the bridge
* To bridge order was taken by 30% against the broad side of the bridge.
2. Brake force load
This style works in the lengthwise direction of the bridge, due to brake and traction force are reviewed for both the traffic department. this effect is taken into account the influence of worth to the brake force at 5% of the charge coefficient D without shock that meets all existing traffic lane in one direction.
3. Due to the style of Temperature Difference
The temperature difference should be determined in accordance with local circumstances. Of C is assumed for the steel and concrete 10. Special review on the incidence of stresses due to temperature differences that exist between parts of the bridge with different materials.
4. Earthquake load
for bridge construction in areas affected by the earthquake, the earthquake load is also taken into account in the planning of the bridge structure
5. Wind loads
wind load is calculated on the bridge construction area that must withstand wind loads.
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