( ) :

Concrete Modulus of elasticity:

1. (cubic strength) , UBC97 . UBC97 (cylindrical strength) 40 32 , 20 10 5 . .

2. UBC97 , 10 (lateral stiffness) (time period) (lateral story drift ratio) . ( value engineering)

3. 2400/3 2450 /3 2480 /3 3.5 .

Stiffness modifiers factors

1. (shear & core walls), (stiffness modifiers) out-of-plane stiffness m11 & m22, in-plane stiffness modifiers f22 & f12 (lateral stiffness) . .

2. / (spandrel beams) (shell elements) , (f22=f12=m11=m22=m12=0.35) (time period) .

3. out of plane stiffness m11 & m22 m12 shell element membrane element

P-Delta

P-Delta , , , P-Delta

:

, : , , , , lanscaping, garbage trolley rooms. . .

Ritz

X,Y & Z. Z response spectrum load case data UZ . (load combinations) ( ).

Wind Load

1. ASCE7-02 , 12 .

2. , , wind exposure type "C" B . exposure type: C exposure type B.

3. wind gust effect factor rigid structure 0.85. flexible tall building structures , 1.1 1.2. 25 25 .

:

flat slab , 30 . (post tension slab) conventional RC slab. 12 25 deflection punching , ACI318 . ( effect of differential shortening of columns) ( ) 27 3 , 65 , ( ).

.asalam 3alaykomawalan i want to put some note on eng. hussein rida

first of all for the material for sure u mention the value of the modulus of elasticity and u are right about it but on this case i must say wuts the formulas for the modulus of elasticity according for the UBC code because usually we use the ACI code to calculate the value of E

ACI318 & UBC97

this is first and second why u didn't mention the strength of the concrete its rich 80 MPA and if u check the model for stresses this value is not enough.this is for the material.

now for the stiffness modifier i didn't get why u want to modifies the vertical load for the shear wall its right just to put the modification on the moment out side and insideand also for the slab.

shell elements

1. Plate elements .

. X Y (plate element) X Y

2. membrane elements . vertical shear wall . X Y Z

:

Plate elements

out of plane deformation elements

Membrane elements

in-plane deformation elements

shell elements

Shell element = plate element + membrane element

shell element stiffness matrix , out of plane stiffness elements in plane stiffness elements

: m11, m22 & m12 out of plane stiffness modifiers (m11, m22 & m12 = 0.35)

in plane stiffness modifiers f11,f22 & f12

:

:

shear walls in plane elements in plane stiffness modifiers out of plane stiffness modifiers

( )

in plane stiffness modifiers out of plane stiffness modifiers

:

in plane stiffness modifiers : f11, f22 & f12 , :

: , f11, f22

f22

f11 .

( )

for the wind pressure ur right for it

--------------------------------and second for the ritx vector u r also right he must remove it but why u didn't mention the value of the SPEC x and The spec Y because they having a strange value 6 and 4

:

: mode shapes modal mass participating ratio 90

: , ( 100% 90% )

:

(65 ) . wind tunnel analysis :

5 3.5 .

mode shapes , .

45 25 ( ) 90 ( 25 ) :

:

1. .

2. (Eigen values & vectors ) .

3. ( ) ( )

4. 25 45 .

.

( )

and why he didn't put the Eccentricity on the SPECX and the SPECY

(5%)

secondly for the mass sources why he didn't put the input 0.25 * L.L

for the P delta analysis u r right

---------------------------------------------------

and secondly for the earth quake even if its seems to be symmetric we must put the EQx2 and EQy2 to take into consideration the effect of the earth quake on the negative way .

, . .

dynamic response spectrum analysis. .

super structure (raft foundation on piles) Safe Safe v12

and why we don't have the raft foundation because its effect a lot on the result of the walls.

, :

full fixity restraints raft foundation piles as springs .

: 60 6 , ( ).

raft foundation as a shell below the tower and the piles as springs.

Soil-Structure interaction .

: geotechnical consultant lateral stiffness of piles under seismic load. piles-assistant-raft

.

:

, , . : frame elements springs( .........)

soil-structure interaction under seismic waves : IBC2009 & ASCE7-05 .

any way all wut i want to say that we must know the tips to check the modelfirst off all check the matirielsthen check the value of the vertical load by tributury area and then check the drift inter story drift = 0.7*R*(ETABS results) < 0.020*story ht or 0.025*story htthen check the displacement due to the wind pressure < h/500on both direction and check the stresses of the wallsand finaly we must have a static analysis to compute the value of the SPECX and THE SPEC Y

this is all i guess we have different things to solve before we continue the discussing but the most important its to check first of all the dynamic analysis and the stability for the tower after modifying all the materials data.

thank u and best regards

ENG bilaland finally hope that some one can inter duce all the steps of checking the model if i missed something

. dear eng. hussein

first of all i want to thank alot for ur explanation espacially concerning the stifnes for the wall but wut i understand from that for the wall espacilly the shear walls u prefer to do m11, m22 & m12 = 0.70 and u will just modify the value of f22 from the list f11, f22 & f12 but by how much u will modify it i mean according to witch code u will modify this value and wut about the f12 . this is for the shear walls and for the slab u will modify m11, m22 & m12 = 0.35 and also u modify the value of f22 from the list f11, f22 & f12 or for the slab there is other consideration to modify the values and if u please to just put witch code u use to modify these value and by how much.and do u guess to calculate the value of the capacity of the concrete f'C usually i check the model the stresses sigma 22 on the plan must not be more then 0.6 F'C other wise u will put a bigger value for the F'c. ! !now for the defining of the earth quake already explain that if u see the definition there is something call + or - on such a model we must consider it i mean u will have 4 earth quake like static value EQX1 for the positive and EQX2 for the negative and EQY1 for the positive and EQY2 for the negativeand after this defintion u will do the static analysis to see the value of SPEC x and the SPECy .wut i concern about is ur point of the design of the raft. usually we put the raft like a slab having a spring Kz=1.2 bearing capacityand kx=ky = 1/3*kzbut in ur case imagine if u have a raft and there is piles under it so do u guess that we must define the raft like a slab having a spring support and u add the piles like spring support :O:O:O *or u define the raft like a slab landing on the piles like a support i mean without springs and if u please try to give me the idea about how u put the piles and according to with formula u use ?????i can put this like an example imagine this tour is landing on a soil that contain water and u decide to put a raft with piles for this tower so how u first of all consider the raft and how u calculate the capacity of the piles and how u put the value for the piles like vertical support :O:O according to wut formula u use this is very good question and wut u define the raft like a slab or a slab having a spring supportand how u can define the piles on this situation.

now for my last point as i understand from u first of all u do the stifness for all element ( wut about the raft any moidification for it ) ???then u define the earth quake

after analysis u check the drift and the participation ratio for the building and the displacement under wind pressure and the stresses for the matiriel

but there is a last thing wut do u guess about the torsion of the building or such tower wut are the condition to check for it if there is and according to any codeand finally thank u for all ur comment and i hope that in the end we can have a clear idea about to understand how we check the etabs model

thank u and best regards

Eng. Bilal

( ) UBC971629.8.3

280 , Zone 2A, UBC97 (Occupancy Category) 16-K : : 1. V Ft ( ) (V-Ft) ( ) . 2. Ft25% V (Ft-max = 0.25V). ( ) . Ft=(0.07T) V T=3.6 sec Ft. 3.6 Ft. 6 7 9 ( 85 ) 25% . 3. Ft 0.7. : (mode shapes) (Time Period) . . . : , ... ( ) ... . ( ) ( ) : . : . . , . : Ft. : 1.Ft . 2. Ft . 3. Ft , 25% : a. 3.6 (Ft-max=0.07xTxV=0.25xV, therefore; T=3.6sec). : 75% . b. ( 73 3.65 ) 60%70% 60%70% 30%40% Ft . ( ) c. : 40% , Ft=0.4xV: , .

: , . , : ( ). .( : , ) 280 7 .

1- ( )

z 5% Ax Ax 1.2

:

: () :Torsional Irregularity (UBC97, table 16-M: plan irregularity type-1)

, 20% ( )

( , ) Ax 30-16 UBC97 3 Ax ,

... f11, f22

F22 ( ) MOMENT NORMAL FORCE TEN COMP , F11 1

RITZ VECTORS , ( ) , , ( MODES EIGN )---------------------------------------------------

dynamic response spectrum analysis. .

ECCENTRCITY , , LOAD COMBINATIONS super structure (raft foundation on piles) Safe Safe v12

SAFE 12 DYNAMIC REACTIONS FIXED OR PINNED SUPPORTS

,

: 60 6 , ( ).

1- SLAB DIAPRAGM ACTION ( )

CORE WALLS ( 60 ) RETAINING WALLS ( DIPHRAGM TRANSFERE DIAPHRAGM

, GROUND BASEMENT

, CORES , CORES RETAINING WALLS GROUND

SLABS GROUND BASEMENTS ( ) CORES

RETAING WALLS , RETAINING WALLS

( -- )

MASS DAMPER (