flat beam question

huangyhg

flat beam question
i need a software or somebody or a research centre for a structural calculation.
i want to calculate the difference in deformation (bending and torsion) of a reinforced concrete flat beam (cm.80x25cm. or cm.100x25cm.) on pillars (cm.30x30cm.) placed at intervals of m.3,50 or more
in the first case the pillars are well-aimed while in the second case on the edge of the beam.
well-aimed
____________________________
     x               x
____________________________
on the edge
______________________
   x             x
______________________
this is very important for me because i am examining a  supporting structure with the latter feature.
and engineering software generally  does not take in consideration this question.
   thanks for your help        
              
ggi,
its difficult to explain adequately as u have not indicated the load pattern! however,
case 1:
u can analyse your continuous beams using any software. this will give u both moments and shear forces.
case 2:
torsion exists only with the case where your beams are off centre. i have assumed 80 or 100cm to be beam width. both beams &  columns will be subjected to torsion. beams will have moments and shear in the other axis too. this should be carried out manually.
i can email to u a spreadsheet based on hardy cross method for analysis of forces in a cont. beam of atleast 5 spans if it helps.
riz
thanks riz
my question is not unmotivated.
you can see the supporting structure:               
dear riz ,
please send me the spreadsheet as it will be of great help to me also.
hiren
the photos have certainly helped but at the same time raised q's.
how old is the building!
is it residential?
is the geo report available?
soil-structure interaction:
quoting " the basement floor and ground have risen" implies that u have an expansive soil which is creeping too.
from the fact that the ground is sloping and an existing non uniform semi-basement, such problems do occur after elapse of many years.
do u have trees in the vicinity. check if they are bowing towards the slope. this will be indicative of your creep problem.
do the buildings in your immediate neighbourhood face the same problem.
is the basement having damp rising problem, find out the water table and its seasonal variation.
what are  the piling depths. find out more about the piles!
eccentricity
the building centroid and centre of gravity loads do not coincide! this eccentricity creates torsional stresses in your structure if subjected to lateral forces or movement associated with sub-soil conditions.
structure
divide your cracks into superficial, moderate and severe cracks. locate serious cracks.
beam having diagonally inclined cracks at or near support implies shear and possibly inadequate depth.
helical cracks in beam face and extending to the outside implies torsional shear stresses.
excessive deflection may be due to inadequate design or overloading.
external walls
if walls are out of plumb than foundation movement must have occured. do u have a ground beam tying all the pile caps?
cracks in masonry also occurs if there is movement or inadequate lateral restraint.
hope this is useful. look for an experienced engineer to assist in your assessment too.
riz
other informations from ggi
the building is ten yers old, but the damages are eight (or more) years old.
yes, it鈥檚 residential
soil- structure interaction
yes the geo report is avilable: i shall write about鈥?in the next days.
yes the soil is an expansive soil (blue clay). under the building there is a little of water that flows down from the hill, so it has been built on special foundations (the piling depth is 12 meters, see image)
i have not trees in the vicinity neither there is a building in my immediate neighbourhood with the same problem.
eccentricity
i鈥檓 worried for eccentricity and i would somebody could calculate (or tell me if a software exists) the deformation of the flat beams. the most worrying cracks are in the walls (inside and outside) on (or near) the flat beams.
structure
the most worrying cracks are red marked on the building plants (see photos):
n.1 : it鈥檚 the effect of the risen or (also) of the pressure of the first floor?
n.2 : in this point there are two little beams broken (like photo n.2). it鈥檚 the effect of the risen or of an inadequate supporting structure? two little beams are broken also at the ceiling of the  second floor (where is 8).
n.3:this is the dividing wall on the same point of the broken little beams (see plants). note: the crack (at the point 6) on the third floor  is like this.  
n.4 (without photo): there is a detached column. it鈥檚 caused by the lack of a pile? (see asterisk and arrow in 鈥渇oundations鈥?. but, perhaps, this pile was important only for the balcony.
n.5: it鈥檚 the most worrying external (and internal) crack.  from the other side of the building there is another like this (but smaller, near the window, n.7)  

besides there are over 150 smaller crack  or superficial crevices in all the building.
i shall continue (perhaps) with other informations.
  
ggi,
your presentation, i admit is very good.
i have understood that you have buildings in your neighbourhood that are sound. were these buildings founded on piles too!
in plain english, u have a big problem and due to the reason that failure started just 2 years after construction was complete implies that sub-soil condition is not favourable.
i will need to go thru your gi report before expounding further.
riz
i pubblished an extract of geo report, but it's not in english. i hope..... somebody will translate for me.
i can say the geo report excludes subsidence of foundations because the rising of the floor is very much: if subsidence the cause, the building would be already collapsed.
see others photos and see better the supporting structure, please. it's a real skeleton?
i have pubblished in
i correct the address:
i rewrite better the address (with the link