Seacliff Stabilization & Foundation Retrofit, San Francisco

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P/A 2018.0523.9894 SAC/DBI (Plans) Approved 9/3/20 ("9894")


P/A 2021.1112.2309 SAC/DBI (Plans) Approved 1/6/22 ("2309")


P/A 2021.1112.2309 SAC/DBI (Details) Approved 1/6/22 ("2309")



10/25/21     Status Quo                                                                                                               12/1/21     Reinforcing of second (final) sequence of not concreted underpinning pits South of Line 4 (9894)


12/1/21     Begin excavation for foundations North of Line 4 (9894/2309)


12/13/21      Reinforcing of second (final) sequence of underpinning pits South of Line 4 (9894)

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12/14/21     Concreting of second (final) sequence of underpinning pits South of Line 4 (9894)
   


1/12/22      Forming over neat-cast grade beams (partial) South of Line 4 (9894)                                                                 Superintendent (Reed DeVost)         Foreman (Alfredo Palma)  



1/13/22     Concreting forms over to be cast-neat grade beams (partial) South of Line 4 (9894)


1/20/22     Continued grade beam construction South of Line 4 (9894)


 1/24/22       Continued construction South of Line 4 (9894)                                 1/27/22      Foundation additions along Line 4 (9894)


 2/3/22     Continued foundation rebuilding along Line 4 (9894)                          2/3/22      Concreting grade beams South of and along Line 4 (9894)


2/3/22     Concreting grade beams South of Line 4 and formed foundation modifications along Line 4 (9894)


2/3/22     No work North of Line 4 (2309) while concreting grade beams South of and along Line 4 (9894)


2/10/22     Set up with conveyor for excavation for foundations North of Line 4 (2309)


2/14/22       Foundation construction South of Line 4 (9894) & readying for excavation North of Line 4 (2309)




2/17/22      Foundation construction South of Line 4 (9894) & excavation in collapsing old fill North of Line 4 to Line 1 (2309)


2/21/22      Foundation construction readying for concrete in garage and underslab area South of Line 4 (9894)


2/22/22 am      Foundation construction readying for concrete South of Line 4 (9894) &  Excavation/shoring of shallow fill North of Line 4 (2309)



2/22/22 pm      Near final concreting grade beams between garage and Line 4, South of Line 4 & readying for shotcreting replacement of SW foundation wall (9894)


2/22/22 pm      Pause in excavation of fill above bedrock under former deck and between existing [2021] drilled shafts North of Line 4 (2309)



2/25/22     Foundation SW of Line 4 (9894) & excavation/shoring of fill above bedrock under former deck and deep between drilled shafts North of Line 4 to Line 1 (2309)


3/4/22     Foundation demolition SW of Line 5 & 4 (9894)



3/4/22     Shoring of fill above bedrock under former deck and deep excavations to weathered bedrock between drilled shafts North of Line 4 to Line 1 (2309)


3/7/22     Foundation wall demolition SW of Lines 5 & 4 (9894)

 


3/7/22     Shoring of fill above bedrock under former deck and deep excavations to weathered bedrock [logged] between drilled shafts North of Line 4 to Line 1 (2309)


3/9/22     Foundation wall demolition SW of Lines 5 & 4 (9894)



3/14/22     Tieback retaining foundation construction N of Line 4 in abeyance (2309) & Shotcrete panel and foundation wall demolition SW of Lines 5 & 4 (9894)



3/16/22     Foundation demolition SW of Lines 5 & 4 (9894) & Excavation/shoring for segments of tieback retaining wall North of Line 4 (2309).




3/18/22     Foundation wall shotcrete preparation SW of Lines 5 & 4 (9894) & Excavation/shoring for staging segments of tieback retaining wall North of Line 4 (2309).




3/22/22     Foundation wall shotcrete preparation SW of Lines 5 & 4 (9894) & Excavation/shoring [construction in abeyance] for segments of tieback retaining wall North of Line 4 (2309).






3/24/22     Concreting footing in preparation for foundation wall shotcrete SW of Lines 5 & 4 (9894).



3/24/22     Continued excavation for tieback retaining wall segments to connect existing drilled shafts N of Line 4 (2309).




3/24/22     Shotcreting foundation wall SW of Lines 5 & 4 (9894).



3/26/22     Shotcrete foundation wall SW of Lines 5 & 4 (9894).



3/28/22     Bushing and drilling existing drilled shafts for connection of tieback retaining wall segments N of Line 4 (2309).



3/31/22     Forming, bushing and drilling existing drilled shafts for connection of tieback retaining wall segments N of Line 4 (2309).


4/1/22     Epoxy grouting reinforcing bars though and doweled into existing drilled shafts to connect tieback retaining wall segments N of Line 4 (2309).


4/4/22     Shotcrete test panel [Norcal] (9894).




4/5/22    Splicing reinforcing bars to dowels at corners and to bars through existing drilled shafts to connect segments of tieback retaining wall to drilled shafts N of Line 4 (2309).



4/7/22    Splicing reinforcing bars to bars through existing drilled shafts and dowels at corners to connect segments of tieback retaining wall to drilled shafts N of Line 4 (2309).



4/11/22    Reinforcing tieback retaining wall segments between drilled shafts N of Line 4 (2309).


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4/19/22    Concreting of all tieback retaining wall segments between drilled shafts N of Line 4 (2309).


4/22/22  Foundation and lateral support (9894/2309)


4/22/22   Wall forming (9894)


5/3/22   Tieback wall (upper) reinforcing for shotcrete (9894)                                                                                                 Interior iron work (9894)                                                                                                                               Ir








5/5/22   Tieback wall (upper) shotcreteing (9894)

      


5/10/22   Framing over completed shotcrete tieback wall (9894)




5/12/22   Framing over completed shotcrete tieback wall (9894)



 5/18/22   Framing/decking over tieback wall and steel beams, constructing struts from tieback wall to building foundation along Line 4 (9894)



5/23/22   Decking over tieback wall and steel beams, grade beam struts from tieback wall to building foundation along Line 4 ready for concrete (9894)



5/27/22   Driveway-street retaining wall foundation, Q decking over tieback wall and steel framing, interior slab preparation (9894)


5/31/22   Driveway-street retaining wall foundation, interior framing, Q decking over tieback wall and steel framing (9894)

  


 


6/3/22   Concreting of grade beam struts between tieback and wall building foundation along Line 4 (2309, 9894)


6/3/22   Forming and reinforcing of foundation integration components (9894)


6/8/22   Driveway-street retaining wall foundation, interior slab reinforcing, strut between tieback wall and building foundation (9894)


6/10/22   Reinforcing for slabs over grade beams, over moisture barrier on aggregate base and Q decking North of garage (2309, 9894)






6/16/22   Concreting of interior slabs over grade beams, base, and decking North of garage (2309, 9894)



6/23/22   Slabs/flatwork finished north of garage, front yard wall forming, base conditioning for garage slab (9894)


6/30/22   Garage slab reinforcing [Norcon & GC] (9894)


7/5/22   Front yard/driveway apron retaining wall and garage slab concreted (9894)


8/1/22   Tieback drilling (2309, 9894)


8/3/22   Tieback drilling (2309, 9894)








8/5/22   Tieback placement, East and center into Radiolarian Chert, right cased 12 ft through fill then into Radiolarian Chert [to design depths] (2309, 9894)






8/8/22   Tieback grouting w/neat cement mix per spec (2309, 9894)`



8/10/22   Tieback grouting, West tieback cased 12' in fill, pulled out 4' leaving 8' in secondary zone.  Start upper/outer framing. (2309, 9894)


8/11/22   Tieback grout lost in foliated Radiolarian Chert gaps (East and Center); to be plugged (2309, 9894)



  8/15/22   Grouting delayed             8/22/22   Tieback grouting resumed w/pea gravel mix to plug gap (East and Center) then pressurized neat cement to complete (2309, 9894)




8/22/22 (cont'd).  Tieback grouting w/pea gravel mix to plug gap, partially fill around plug and up, then pressurized neat cement to complete (2309, 9894)


9/20/22  Misc                                                                                  9/29/22   Tieback pull-out testing (2309, 9894)



9/29/22  Clean-up & tension testing at 140% of design & lock off at design load (2309,9894)                                                                                                                              



 


9/29/22  Tieback Threadbar tension strength testing at 140% of design load & lock off at design load; interior framing & view (2309, 9894)


9/29-10/19/22  Miscellaneous views from building extension & coal tar epoxy spec for corrosion protection of tieback anchorages (2309, 9894)


10/19/22  Coal tar epoxy corrosion protection for tieback anchorages - Left to Right = East to West (2309, 9894)


7/5/23  San Francisco Bay Low Tide 8:00 am


 SS&S Ordinance, Structural Advisory Committee, CCSFDBI Permit


San Francisco Bay Tides & Currents

Bluff Edge Pool and Wall, San Francisco

Golden Gate Bridge - San Francisco to Marin County

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