Analysis and Design
I. Analysis Assumption
The culvert shall be designed and analyzed by the Strength Design Method (Load Factor Design).
The box culvert shall be analyzed, as a rigid frame with all corner connections considered rigid.
Sidesway is not considered in analysis.
II. Loading For Box Culvert
a. Factored loads for ultimate design capacity.
b. Unfactored loads for serviceability checks.
a. Culvert concrete : fc’ = 20.7MPA (3000psi)
b. Reinforcing steel : fy = 275MPA (Grade 40)
c. Soil Properties: ka = 0.33(Active coef. of friction) for Ø=30 deg. Internal angle of friction of soil.
IV. Dead Loads and Earth Pressures
a. Unit weight of reinforced concrete: wc = 23.6KN/m3(150pcf)
b. Unit weight of soil: ws = 23.6KN/m3 (150pcf)
V. Live Loads
a. Live Load for driveways: wL = 12 kpa (surcharge) (NSCP)
VI. Lateral Loads
a. Equivalent Fluid Pressure
LOADS ( CONSIDERING 1M STRIP ALONG CULVERT)
Ru = Soil pressure reaction
WP = Uniform weight of pavement
WPE = Equivalent fluid pressure due to soil
WLP = Equivalent fluid pressure due to pavement weight
WS = Uniform weight of soil above culvert
WC = Uniform weight of culvert
WLS = Uniform weight of live load
WLL = Equivalent fluid pressure due to live load(surcharge)
|Structure Type |SPACE FRAME |
|Number of Nodes |4 |Highest Node |4 | |Number of Members |4 |Highest Members |4 |
|Number of Basic Load Cases |2 | |Number of Combination Load Cases |1 |
|Type |L/C |Name | |Primary |1 |DEAD LOAD | |Primary |2 |LIVE LOAD | |Combination |3 |1.4DEAD LOAD + 1.7LIVE LOAD |
|Member |Node A |Node B |Length |Property |β | | | | |(m) | |(degrees) | |1 |1 |2 | 1.000 |1 |0 | |2 |3 |4 | 1.000 |1 |0 | |3 |1 |3 | 1.000 |1 |0 | |4 |2 |4 | 1.000 |1 |0 |
|Node |X |Y |Z | | |(m) |(m) |(m) | |1 | 0.000 | 0.000 | 0.000 | |2 | 1.000 | 0.000 | 0.000 | |3 | 0.000 | 1.000 | 0.000 | |4 | 1.000 | 1.000 | 0.000 |
Basic Load Cases
|Number |Name | |1 | DEAD LOAD | |2 | LIVE LOAD |
Combination Load Cases
|Comb. |Combination L/C Name |Primary |Primary L/C Name |Factor | |3 |1.4DEAD LOAD + 1.7LIVE LOAD |1 |DEAD LOAD...