MEMO
Bureau of Structures and Geotechnical Services
DATE: June, 8 2016 TO: John Jones, P.E. Assistant Bureau Chief-Bureau of Structures and Geotechnical Services
ATTENTION: Chris Meyer, P.E. Senior Bridge Squad Leader
FROM: Denny J. Martin, P.G. Regional Geologist
RE: Bridge Foundation Geology Report Addendum Project 69-19 KA-1554-03 US-69 over Dry Branch Cox Creek Bridge No. 69-19-17.74 (135) Crawford County, Kansas
____________________________________________________________ The Bridge Foundation Geology Report Addendum for the above referenced project is enclosed. This addendum makes changes to the spread footing plan notes within the initial Bridge Foundation Geology Report for this project. The addendum can be found on the OnBase document management system. If there are questions over the contents of this addendum contact the Chanute Regional Geology Office at (620) 431-1000 or by the following emails:
[email protected] or
[email protected]. Attachments cc:
Susan Eiseman, Assistant Bureau Chief-Construction and Materials James Metcalfe, P.E., District 4 Construction/Materials Engineer George Dockery P.E., Area 4 Engineer Brent Slade, Change Order Technician Angie Hoover, Bridge Management System Analyst Debbie Stanley Regional Geology Offices Project File
BRIDGE FOUNDATION GEOLOGY REPORT ADDENDUM 69-19 KA-1554-03 Bridge No. 69-19-17.74 (135) NB US-69 over Dry Branch Cox Creek 2.4 Miles North of Arma City Limits Crawford County ROBERT W. HENTHORNE, P.G. CHIEF GEOLOGIST By: Tyson LeSage, Geology Associate Denny J. Martin, P.G., Regional Geologist June 2016
Bureau of Structures and Geotechnical Services Geology Section
69-19 KA-1554-03 Bridge No. 69-19-17.74 (135) NB US-69 over Dry Branch Cox Creek 2.4 Miles North of Arma City Limits Crawford County
INTRODUCTION This addendum is being issued to address an outdated spread footing plan note within the Bridge Foundation Geology Report for this project. The following revised notes should replace the spread footing notes in the initial report. Spread Footing Plan Notes (Revised) The following notes should be placed in the construction plans if spread footings are chosen as the foundation elements of the Piers: “Foundation verification is necessary for this footing. A 5.0 foot deep hole will need to be drilled in the bearing material in the presence of the field engineer to verify the quality and soundness of the bearing material. For footings smaller than 64.0 ft.2 drill one hole in the center of the footing, and for footings larger than 64.0 ft.2a hole should be drilled at each corner.” “All excavation below the top of the footing within 3.0 feet of the edge of the footing will be done by hand equipment only, no machine rock excavation is allowed below the top of the footing. Blasting is not permitted for excavation of the spread footings. Cut the rock to neat lines as shown in the plans. Do not use side forms but cast the concrete against the rock. Allow no loose material within the excavation when the footing is considered ready to pour. If the material at the bottom of the footing does no match the material shown on the geology sheet, do not continue until the Regional Geologist reviews the site.” “If a fissure or joint is found in the position of the footing material, the footing will need to be cleaned out to suitable material and filled according to specifications under the approval of the field engineer.” “Do not allow water to pond in the footing excavation pit. Once the excavation is complete, place the reinforcing steel and concrete in the excavation in less than 24 hours to minimize the exposure time of the founding rock. If water is persistent in the excavation, then place the concrete by tremie method. Do not allow concrete to be placed on or through water where mixing or washing of the concrete can occur. Do not allow concrete to be placed if water is moving through the footing.”
