14747 October 2004

Further Use of Spread Footing Foundations for Highway Bridges (State Job No. 14747) : Further Use of Spread Footing Foundations for Highway Bridges (State Job No. 14747) Presentation @ Ohio DOT By Masada & Sargand (ORITE) 1-2 p.m. October 4, 2004


Project Objectives : Project Objectives Instrument & monitor spread footing foundations at additional highway bridge construction sites in Ohio. Combine data from the previous & current studies to assess overall applicability of spread footing as a highway bridge foundation alternative. Discuss limiting soil conditions for the use of spread footing.


Project Objectives (cont’d) : Project Objectives (cont’d) Evaluate reliability of field performance prediction methods available for spread footing foundations. Examine the economic aspect of using the spread footings for highway bridges, instead of deep foundations.


Background : Background Studies by Cheney et al. (1982) & by DiMillio (1982) Highway bridges can sustain substantially more tilting (up to 1/250 of the span) and settlement (up to 3 inches) than what was previously considered. Studies by Amar et al. (1984) & by Briaud (1997) The cost associated with the spread footing is 30-80% less than the cost of deep fundations. About 50% of the bridge construction cost may be spent on foundations.


Background (cont’d) : Background (cont’d) Previous Spread Footing Study by ORITE Final report by Sargand et al. (1997). Instrumented & monitored 50 spread footings at 5 highway bridge construction sites in Ohio. 3 bridges resting on cohesionless soils, 2 bridges on cohesive soils --- SPT N-value > 30. No spread footings settled more than 2 inches. No differential settlement problem encountered.


Progress Report (Summary) : Progress Report (Summary) FRA-670-0.38 Site Instrumented central pier footing Monitored its field performance for 7 months MOT-70/75 Interchange Site Instrumented Pier 19 (Ramp C) footing Monitored its field performance for 2 months Instrumenting Pier 18 (Ramp C) footing


Field Instrumentations : Field Instrumentations Contact pressure magnitude & distribution through earth pressure cells Settlement of monitoring points through optical level surveying Pier column/wall tilting through tilt-meter


Field Instrumentations (cont’d) : Field Instrumentations (cont’d) Footing Wall Settlement Points Tilting Contact Pressure Riser Pipe Contact Pressure Instrumentation Schemes for Spread Footing Foundation Soil Fill


Field Instrumentations : Field Instrumentations Settlement Points Installed in Footing


Field Instrumentations : Field Instrumentations Pressure Cell Installation – Step 1


Field Instrumentations : Field Instrumentations Pressure Cell Installation - Step 2


Field Instrumentations : Field Instrumentations Pressure Cell Installation - Step 3


Field Instrumentations : Field Instrumentations Pressure Cell Installation – Step 4


Field Instrumentations : Field Instrumentations Pressure Cell Installation – Step 5


Field Installations : Field Installations SINCO Tilt-meter System


Field Installations : Field Installations Tilting Reference Plate


FRA-670-0.38 Central Pier : FRA-670-0.38 Central Pier Bridge = High St. Over I-670 (Spans 102.9’ & 100.2’) Subsurface Condition (Borings RB-11) At least 25’ of br. sand, some gravel, little silt (N = 40-70; A-3a) Spread Footing 8’ (W) x 40.3’ (L) x 3’ (H)  A = 322 ft2 Construction Dates Excavation (2-28-03); Footing Const. (36 yd3,3-7-03); Columns Construction (17 yd3,3-20-03); Backfilling (3’ Cover, 4-1-03); Cap Const. (15 yd3, 4-2-03); Barrier Wall Const. (10 yd3, 4-25-03); Girder Beams Placement (200 tons, 5-22-03); Deck Const. (327 tons, 6-24-03); Bridge Opening (7-29-03).


FRA-670-0.38 Central Pier : FRA-670-0.38 Central Pier Pressure Cell Installation Plan Edge of Spread Footing Pressure Cell (precast in concrete block) C L C L 1’-6” 1’-6” 4’-6” 4’-3” 20’-3” 20’-0” 4’-0” 4’-0” N #59236 #59237 #59233 #59238 #59231 15’-0” East Column


FRA-670-0.38 Central Pier : FRA-670-0.38 Central Pier Edge of Spread Footing Bolt (used as a settlement monitoring point) Settlement Monitoring Point Location Plan 4’-3” 4’-6” 1’-6” 1’-6” 20’-0” 20’-3” N 4’-0” 4’-0” NE NW SE SW C


FRA-670-0.38 Central Pier : FRA-670-0.38 Central Pier Edge of Spread Footing Tilting Monitoring Station Location Plan 4’-3” 4’-6” 20’-0” 20’-3” N 4’-0” 4’-0” 31’-6”   E. Col. W. Col.


FRA-670-0.38 Central Pier : FRA-670-0.38 Central Pier Site Conditions on April 15, 2003


FRA-670-0.38 Central Pier : FRA-670-0.38 Central Pier Site Conditions (Girder Beams Placed) on May 28, 2003.


FRA-670-0.38 Bridge : FRA-670-0.38 Bridge The bridge was opened to the traffic on July 29, 2004


FRA-670-0.38 Bridge : FRA-670-0.38 Bridge Settlement Detected at NE Point 2 = Footing; 3 & 4 = Columns; 5 = Cap + Backfilling; 6-8 = Barrier Wall; 9 & 10 = Girder Beams; 11 = Deck Const.


FRA-670-0.38 Bridge : FRA-670-0.38 Bridge Settlement Detected at NW Point 2 = Footing; 3 & 4 = Columns; 5 = Cap + Backfilling; 6-8 = Barrier Wall; 9 & 10 = Girder Beams; 11 = Deck Const.


FRA-670-0.38 Bridge : FRA-670-0.38 Bridge Settlement Detected at Center Point 2 = Footing; 3 & 4 = Columns; 5 = Cap + Backfilling; 6-8 = Barrier Wall; 9 & 10 = Girder Beams; 11 = Deck Const.


FRA-670-0.38 Bridge : FRA-670-0.38 Bridge 1-3 = Footing Const.; 4 = Columns Const.; 5 = Cap + Backfilling; 6-8 = Barrier Wall; 9 & 10 = Girder Beams; 11 = Deck Const.; 12-14 = After Opening


FRA-670-0.38 Bridge : FRA-670-0.38 Bridge 1-3 = Footing Const.; 4 = Columns Const.; 5 = Cap + Backfilling; 6-8 = Barrier Wall; 9 & 10 = Girder Beams; 11 = Deck Const.; 12-14 = After Opening


FRA-670-0.38 Bridge : FRA-670-0.38 Bridge 1-3 = Footing Const.; 4 = Columns Const.; 5 = Cap + Backfilling; 6-8 = Barrier Wall; 9 & 10 = Girder Beams; 11 = Deck Const.; 12-14 = After Opening


FRA-670-0.38 Bridge : FRA-670-0.38 Bridge 1-3 = Footing Const.; 4 = Columns Const.; 5 = Cap + Backfilling; 6-8 = Barrier Wall; 9 & 10 = Girder Beams; 11 = Deck Const.; 12-14 = After Opening


FRA-670-0.38 Bridge : FRA-670-0.38 Bridge East Column


FRA-670-0.38 Bridge : FRA-670-0.38 Bridge West Column


MOT-70/75 Interchange Reconstruction : MOT-70/75 Interchange Reconstruction Ramp C


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) Span = 118.1’ (between Piers 18 & 19) = 88.6’ (between Pier 19 & Forward Abutment) Subsurface Condition (Boring C188) At least 34’ of gr. sandy silt, some clay, tr. gravel (N = 53-79; A-4a) Spread Footing 24’ (W) x 49.2’ (L) x 4.4’ (H)  A = 1181 ft2 Construction Stages Excavation (8-09-04); Footing Const. (195 yd3, 8-24-04); Wall Const. (124 yd3, 9-13-04); Backfilling (4’ thick, 9-22-04). * Scheduled to be opened to traffic in the fall 2005.


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) Pressure Cell Installation Plan Edge of Spread Footing Pressure Cell (precast in concrete block) C L C L 3’-0” 3’-0” 4’-6” 4’-6” 24’-7” 24’-7” 12’-0” 12’-0” N #59228 #59227 #04-2364 #04-2369 #59235


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) Edge of Spread Footing Bolt (used as a settlement monitoring point) Wall Settlement Monitoring Point Location Plan 4’-6” 4’-6” 2’-6” 2’-6” 24’-7” 24’-7” 17’-2” 17’-2” N 1’-10” 1’-10” 12’-0” 12’-0” 6’-0” = ORITE = Contractor LEGEND


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) Field Conditions As of Sept. 30, 04


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) 2-4 = Footing Const.; 5 & 6 = Wall Const. 7 & 8 = Backfilling


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) 2-4 = Footing Const.; 5 & 6 = Wall Const. 7 & 8 = Backfilling


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) 2-4 = Footing Const.; 5 & 6 = Wall Const. 7 & 8 = Backfilling


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) 2-4 = Footing Const.; 5 & 6 = Wall Const. 7 & 8 = Backfilling


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) 4 = Footing Const.; 5 & 6 = Wall Const. 7 = Backfilling


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) 4 = Footing Const.; 5 & 6 = Wall Const. 7 = Backfilling


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) 4 = Footing Const.; 5 & 6 = Wall Const. 7 = Backfilling


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) 4 = Footing Const.; 5 & 6 = Wall Const. 7 = Backfilling


MOT-70/75 Pier 19 (Ramp C) : MOT-70/75 Pier 19 (Ramp C) 4 = Footing Const.; 5 & 6 = Wall Const. 7 = Backfilling


MOT-70/75 Pier 18 (Ramp C) : MOT-70/75 Pier 18 (Ramp C) Span = 134.5’ (between Piers 17 & 18) = 118.1’ (between Piers 18 & 19) Subsurface Condition (Boring C187) At least 38’ of gr. sandy silt, some clay, tr. gravel (N = 15-62; A-4a) Spread Footing 17.7’ (W) x 57.4’ (L) x 4.4’ (H)  A = 1016 ft2 Construction Stages Excavation (9-21-04); Footing Const. (199 yd3, 9-27-04); Wall Const. (10-07-04?). * Scheduled to be opened to traffic in the fall 2005.


MOT-70/75 Pier 18 (Ramp C) : MOT-70/75 Pier 18 (Ramp C) Pressure Cell Installation Plan Edge of Spread Footing Pressure Cell (precast in concrete block) C L C L 3’-0” 3’-0” 4’-6” 4’-6” 28’-8.5” 28’-8.5” 8’-10” 8’-10” N #59234 #59229 #04-2368 #04-2365 #04-2367 #04-2366 #59232


MOT-70/75 Pier 18 (Ramp C) : MOT-70/75 Pier 18 (Ramp C) Edge of Spread Footing Eyebolt (used as a settlement monitoring point) Wall Settlement Monitoring Point Installation Plan 4’-6” 4’-6” 2’-6” 2’-6” 28’-8.5” 28’-8.5” 20’-6” 20’-6” N 8’-10” 8’-10” 1’-10” 1’-10” 6’-0” = ORITE = Contractor LEGEND


MOT-70/75 Pier 18 (Ramp C) : MOT-70/75 Pier 18 (Ramp C) Field Conditions As of Sept. 30, 04


MOT-70/75 Forward Abut. (Ramp C) : MOT-70/75 Forward Abut. (Ramp C) Forward Abut. Field Conditions As of Sept. 30, 04


Data Analysis : Data Analysis Contact Pressure Field: q = C(R0-Ri) + K(T0-Ti) where C = calibration factor; R0 = initial transducer reading; Ri = i-th transducer reading; K = thermal correction factor; T0 = initial transducer temperature; and Ti = i-th transducer temperature. Theory: q = (P/A) + (M/S) where P = dead load; A = footing base area; M = overturning moment; and S = section modulus.


Data Analysis : Data Analysis Wall/Column Tilting Field: q = sin-1[0.5(R+ – R-)] where R+ = (+) reading; and R- = (-) reading. Theory: q = tan-1[{(1-m2)/Es}{M/B2L}Iq] where m = Poisson’s ratio; Es = Young’s modulus of soil; M = overturning moment; B = footing width; L = footing length; and Iq = influence factor.


Data Analysis : Data Analysis Immediate (Elastic) Settlement Theory: Se = qB(1-m2)I7/Es where q = pressure; B = footing width; m = Poisson’s ratio; I7 = lumped parameter; Es = Young’s modulus of soil. Beyond Immediate Settlement - Apply primary consolidation theory for footings on cohesive soils. - Apply several different methods (by Hough, Terzaghi-Peck, Peck-Bazaraa, D’Appolonia, Burland-Burbridge, Schmert-mann) for footings on cohesionless soils.