Limit equilibrium methods- Depth of soil affected by abutment movement can be identified without soil-structure interaction analysis
- Thermal movement ≤ 40 mm;
- Skew ≤ 30°
PD 6694-1:2011 9.4.4 Horizontal soil pressures on end screen and abutments that accommodate thermal movements by translation without rotation
Applying Temperature Loads and Results
Apply Earth Pressure based on PB6694-1
Envelope Results by Load Combination
Example #2. Integral bridge with full height abutments supported on a single row of piles
Soil–structure interaction- Depth of soil affected by abutment movement cannot be easily identified unless a soil-structure interaction analysis is performed
- Thermal movement > 40 mm;
- Skew > 30°
- Over-consolidated back-fill material
- Layered soils
PD 6694-1:2011 9.4.5 Horizontal earth pressures on full height frame abutments on piles and embedded wall abutments (soil– structure interaction analysis)
Soil structure interaction model can be generated with midas GTS NX. In order to consider the variable elastic modulus, we can imply import the materiel properties from Excel into GTS NX and assign them to each soil layers.
Construction stage analysis with 5 stages considering structure and back-fill soil construction with temperature loads has been performed. The stress profile from soil is obtained and compared with earth pressure applied to abutment to obtain H'(depth of soil influenced by the abutment movement) and d'(the moment of the structure at a depth H'/2 due to an expansion or contraction of the end of deck). Update Soil Shear Modulus, R_FG, and young's modulus in GTS NX model file and update the results again. By doing this iterative analysis again, we can obtain the converged results.