L e xing to n I I Pre se nta tio n Outline a t Ma rke t Sq ua re - PDF document

L e xing to n I I Pre se nta tio n Outline a t Ma rke t Sq ua re No rth, Wa shing to n D.C. Building Summa ry E xisting Struc ture Pro po sa l Gra vity Syste m L a te ra l Syste m Othe r Struc tura l F a c to rs Co nstruc tio n Ma na g e me nt Me c ha nic a l Co nc lusio n Ale xis Pa c e lla – Struc tural Optio n Building Summa ry Building Summa ry 12 Sto ry Re side ntia l T o we r Ma rke t Sq ua re No rth Co mple x 3 b e lo w g ra de le ve ls 72,000 sq ft 49 Apa rtme nt Units Co mple te d in 2002 Pre se nta tio n Outline E xisting Struc ture Building Summa ry Gra vity Syste m: E xisting Str uc tur e 2 Wa y F lat Plate Slab Pro po sa l 8 inc he s Gra vity Syste m I rre g ula r Co lumn L ayo ut Small Ba ys L a te ra l Syste m Othe r Struc tura l F a c to rs L a te ra l Syste m: Co nstruc tio n Ma na g e me nt She a r Wa lls Me c ha nic a l Co nc lusio n F o unda tio n: MAT 1

Pre se nta tio n Outline Pro po sa l Building Summa ry E xisting Struc ture Cur r e nt de sign r e str ic te d by he ight limit: 130 fe e t (c ur r e nt he ight = 125 ft w/ pe nthouse ) Pr oposal Gra vity Syste m Only str uc tur e s with a thin floor sandwic h, suc h as flat L a te ra l Syste m plate and pr e -stre sse d we r e c onside r e d Othe r Struc tura l F a c to rs Whe n he ight r e str ic tion is not a fac tor , Co nstruc tio n Ma na g e me nt Can A More E c onomic Syste m be Me c ha nic a l F ound??? Co nc lusio n Pro po sa l Pre se nta tio n Outline Building Summa ry E xisting Struc ture Ho w will a ste e l struc tura l syste m e ffe c t… Pro po sa l Othe r b uilding syste ms Gr avity Syste m L a te ra l Syste m T ime Othe r Struc tura l F a c to rs COST Co nstruc tio n Ma na g e me nt Me c ha nic a l Co nc lusio n Gra vity Syste m Gra vity Syste m Composite : Ne w c olumn layout r e quir e d for ste e l syste m to be Ste e l c o mpo site de c k o n ste e l b e a ms a nd e c onomic al c o lumns Doe s not inte r fe r e Re la tive ly shallo w flo o r sa ndwic h w/ ar c hite c tur e No la rg e c ha ng e in stiffne ss a nd vib ra tio n Windows move d Ste e l is usually mo st c o st e ffe c tive One c lose t obstr uc te d Additio nal c o st a nd la b o r fo r fire pro o fing a nd c o nne c tio ns 2

Gra vity Syste m Gra vity Syste m Be ams, c olumns, and she ar studs we r e de signe d for Composite De c king: gr avity loads using RAM softwar e . Spa n is to o lo ng , b ise c t e a c h b a y with a b e a m Unsho re d sa ve s o n la b o r a nd ma te ria l Unsho re d will use e xtra c o nc re te R e side ntial L e ve ls: 2” L OK floor de c k with 4.5” slab Public L e ve ls: 3” L OK de c k with 5.5”slab 3 rd E De c king c ho se n fro m USD c a ta lo g . RAM c rite ria se t to L RDF ditio n Gra vity Syste m Pre se nta tio n Outline Building Summa ry F inal De sig n: E xisting Struc ture Pro po sa l 4.5” de c k + slab Gra vity Syste m 12” b e a m L ate ral Syste m Othe r Struc tura l F a c to rs = 16.5” T otal floor sandwic h de pth Co nstruc tio n Ma na g e me nt Me c ha nic a l nc re a se o f 8.5” pe r flo o r � 8.5’ to ta l I Co nc lusio n Ne w He ig ht = 133.5’ > Allo wa ble 130’ L a te ra l Syste m L a te ra l Syste m 3 po ssible L a te ral Syste ms: She ar Walls: She a r Wa lls Che c k E xisting Walls Mo me nt F ra me s E T ABS Bra c e d F ra me s R e sults: L oc ate d ar High str Will not obstr e ngth and stiffne ss ound e le vator uc t bays shaft Sur r ound E le vator Shaft Ar c hite c tur Costly c onne c tions al F E asy to e r e atur e of the building e c t Ste e l � L We ight � L ighte r e ss Se ismic L oad e ase � Slightly Gre ate r 8.5’ he ight inc r Wind L oad 3

L a te ra l Syste m L a te ra l Syste m Br ac e d F r ame s: ST AAD De sig n: F ind lo c a tio n in b uilding Distrib ute L o a ds b y Rig idity Che vro n Bra c e s Che c k ASCE 7 wind c a se s Me mb e r Stre sse s Co ntro lle d De sig n, c he c k o n ST AAD Size Ra ng e : W12x65 – W12X170 De sign was c ontrolle d by T o tal De fle c tio n < 3.6” a llo wa ble allowable str e ss L a te ra l Syste m Pre se nta tio n Outline F inal De sig n: Building Summa ry So me c o lumns c o ntro lle d E xisting Struc ture b y b ia xia l b e nding � Pro po sa l inc re a se d size Gra vity Syste m ⎛ ⎞ L a te ra l Syste m Pu Mux Muy ⎜ ⎟ + + ≤ ⎜ ⎟ 1 φ φ φ ⎝ ⎠ 2 Pn Mnx Mny Othe r Str uc tur al F ac tor s Co nstruc tio n Ma na g e me nt Size s: W12x65 – W14x342 Me c ha nic a l F ina l De fle c tio n = 2.7” Co nc lusio n < 3.6” a llo wa b le Othe r Struc tura l F a c to rs Othe r Struc tura l F a c to rs Be am to Column Conne c tions: Are the re o the r issue s with the struc ture to b e c o nside re d? Stiffe ne rs Re q uire d Co nne c tio ns Sub struc ture F o unda tio n ypic a l 7 th flo o r c o nne c tio n T 4

Othe r Struc tura l F a c to rs Othe r Struc tura l F a c to rs He avy Br ac ing Conne c tion: T he Sub struc ture : Unifo rm F o rc e Me tho d Co nc re te is b e tte r in sub te rra ne a n Sa me b e a m to c o nditio ns c o lumn c o nne c tio n Additio na l b uilding we ig ht 27”x27”x1/ 2” g usse t Co nc re te is a mo re dura ble pa rking pla te struc ture 3”x3”x1/ 2” a ng le s ypic a l 7 th flo o r c o nne c tio n T Othe r Struc tura l F a c to rs Othe r Struc tura l F a c to rs Sub struc ture : Sub struc ture : Girde rs: 24”x15” One wa y jo ist flo o r ~e a sy to c o nstruc t to p ste e l = 7 # 9’ s ~wo rks with ne w b a y size s b o tto m ste e l = 4 # 8’ s Girde r Se c tio n 20” pa ns; 5” rib s; 25” o .c . Re info rc e me nt Cuto ffs Stirrup Pla c e me nt Othe r Struc tura l F a c to rs Othe r Struc tura l F a c to rs Sub struc ture : Sub struc ture : Co lumns: Be lo w the Bra c e d F ra me s: Co nne c tio ns ~ a b a se pla te sunk into flo o r sla b a t e a c h c o lumn She a r wa lls we re use d, she a r c o ntro lle d 5

Pre se nta tio n Outline Othe r Struc tura l F a c to rs F o unda tio n: Building Summa ry E xisting MAT fo unda tio n E xisting Struc ture Pro po sa l Punc hing she a r Gra vity Syste m Ove rturning L a te ra l Syste m Othe r Struc tura l F a c to rs No Pr oble ms Constr uc tion Manage me nt Me c ha nic a l Co nc lusio n F o rc e s a ffe c ting o ve rturning Co nstruc tio n Ma na g e me nt Co nstruc tio n Ma na g e me nt Site L a yo ut: Co nstruc tio n Ma na g e me nt I ssue s: Ne e de d spa c e s: o ffic e s, c irc ula tio n Site L a yo ut pa ths, sto ra g e , e tc … Co st Ste e l De sig n ~ Cra ne Sc he duling ~ L a y Do wn Are a Co nstruc tio n Ma na g e me nt Co nstruc tio n Ma na g e me nt Co st : Co nc re te ......................................$1,526,000 Ste e l ………………………………...$1,455,600 Save s $70,000 Building Sc ale is no t la rg e e no ug h to T his do e s no t ho we ve r a c c o unt fo r c o st de ve lo p full e c o no my a sso c ia te d with a due to e xtra fa ç a de ma te rial o r ste e l struc ture fire pro o fing 6

Pre se nta tio n Outline Co nstruc tio n Ma na g e me nt Building Summa ry Sc he duling : E xisting Struc ture E a c h le ve l is built in the se q ue nc e : Pro po sa l 1 da y fo r c o lumns a nd b e a ms Gra vity Syste m 2 da ys fo r de c k L a te ra l Syste m Ne xt le ve l is sta rte d Othe r Struc tura l F a c to rs Sla b s po ure d whe n b e a m, c o lumn, a nd de c k Co nstruc tio n Ma na g e me nt c o nstruc tio n is 3 sto rie s a he a d. Me c hanic al T o ta l: 18 we e ks Co nc lusio n Me c ha nic a l Me c ha nic a l HVAC: Me c ha nic al Co nside ra tio ns: F re sh a ir re q uire me nts a re me t b y windo ws HVAC Ac o ustic s Me c ha nic a l Me c ha nic a l HVAC: ME P Syste ms c a n b e mo ve d fro m so ffits into c e iling sa ndwic h. Be a ms sho uld no t b e inte rse c te d . E xha ust Supply 7

Me c ha nic a l Me c ha nic a l Ac o ustic s: Ac o ustic s: Orig inal Syste m: Co nc re te c e iling s with Ac o ustic T ile s o n suspe nde d c e iling spra ye d a c o ustic a l se ala nt Asse mbly I ssue s NRF = .75 Ste e l Syste m: Suspe nde d c e iling with a c o ustic a l tile s NRF = .5 to .95 Pre se nta tio n Outline Co nc lusio ns Building Summa ry E xisting Struc ture Str uc tur al de sign was c ontr olle d by he ight r e str ic tion Pro po sa l Composite : Gra vity Syste m L ar ge r Bays L a te ra l Syste m Othe r Struc tura l F a c to rs Wor ks we ll with othe r inte grate d syste ms Co nstruc tio n Ma na g e me nt F ull E c onomy of Ste e l Savings was not ac hie ve d Me c ha nic a l Conc lusion Que stions? 8