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 Ahmad Wani posted on Friday, July 30, 2010 - 05:41 am
i wanted to clarify one thing.
if we r providing steel frames(for seismic resistance) on the outer walls maintaining a ratio of openings to perimeter = .5 .. now, at the same time, can i provide a life core wall in the structure (using steel frames), in the internal wall as well, maintaining a ratio of .5 in it separately for the inner wall?
 Wendy Daniell posted on Saturday, July 31, 2010 - 10:08 am
Hi Ahmad

The answer is dependent on what is inside your core wall.

If the inner core wall is an external wall surrounding an open courtyard, then you must still maintain the ratio of openings to perimeter=0.5.

If the inner core wall is a wall surrounding an internal area of the building, e.g. a lift shaft or room, then you must ensure there is an opening into that area. See Rule 7 of the Rules for the Structure at
http://www.ideers.bris.ac.uk/dynamicdesigns/structure.html

I hope this ansewers your question.
 Ahmad Wani posted on Saturday, July 31, 2010 - 11:46 am
Thank u for the reply,
i have already provided a shear wall on the outside (and provided the ratio of 0.5),
now, at the same time, can i provide a core wall (as a lift wall)in the interior of the building?
 Wendy Daniell posted on Saturday, July 31, 2010 - 01:40 pm
Yes, but you must obey Rule 7 of the Rules for the Structure. For some examples of how to leave an opening in your core wall. Hold your mouse cursor over the words "Show Me" in Rule 7 to see some photographs.

Don't worry too much about this because when you send us sketches of your ideas we will definitely let you know if you are breaking the rules before you submit your posters. Don't forget that you get 2 opportunities to run your ideas past us without the other teams seeing what you are planning.
 G. Krishnakumar posted on Monday, August 02, 2010 - 10:24 am
Sir,
Can we use material like spring for our model designing apart from the materials specified like Paper, MDF etc
 Adam Crewe posted on Monday, August 02, 2010 - 10:37 am
I'm afraid that you can only use the materials that will be provided but you can use these in any way you want.

If you think creatively you may be able to get close to what you are trying to achieve.
 G. Krishnakumar posted on Sunday, August 08, 2010 - 05:14 pm
Sir,
Can the use any of the materials provided to design the floors in our model, or is there any specific material is to be used?
 Wendy Daniell posted on Sunday, August 08, 2010 - 07:24 pm
Hello

You will be provided with the materials set out in the "Specification in for the model building". These are the only materials that you will have to construct your model. You can use them in any way you like for any element of your structure and you can be as creative as you like too. Of course, whatever you build must be able to carry the forces that the structure is subjected to.

I hope this helps.
 G. Krishnakumar posted on Monday, August 09, 2010 - 08:30 am
Sir,
Which is the better shape for the model structurally, circular or square?
 Wendy Daniell posted on Monday, August 09, 2010 - 08:43 am
Hello

You could argue that a circular building would be a better shape, as you don't know from which direction the main shaking of the earthquake will be. Therefore a circular building would be designed to have the same resistance in all directions assuming that it is axisymmetric. Of course a circular model is difficult to construct so you could go for a heaxgonal or octagonal building instead.
 G. Krishnakumar posted on Monday, August 09, 2010 - 11:11 am
Thank you very much sir
 Jaykrishnan A posted on Tuesday, August 10, 2010 - 01:49 pm
Hello

Wont a frame with an assymetrical plan like a pentagon or heptagon be better for seismic resistance, considering that the frame will be able to resist seismic wave action from 5 and 7 different directions respectively.
 Adam Crewe posted on Tuesday, August 10, 2010 - 02:27 pm
The shake that your models will be subjected to will be a horizontal circular motion with a varying frequency and amplitude. This motion will test all axes of your model, so a model with a reasonable about of stffness in all directions is likely to perform best. If the building has the same stiffness in all possible axes it would probably perform very efficiently. This would be something like a circular tube. Unfortunately this structure would not obey the rules and would also be difficult to build. A 5, 6 or 7 sided structure is an reasonable approximation to a tube and should perform well. However I'm not sure however that having an odd number of sides is any better than an even number. For me the ability to effieicntly build the model building would start being more important than small increases in structural efficiency.
 Jaykrishnan A posted on Tuesday, August 10, 2010 - 04:25 pm
Thanks for answering the query.
 S.Ugeeshan posted on Thursday, August 12, 2010 - 09:48 am
sir
as you mentioned your model specification maximum floor area per floor as 320sq.cm.Not counting ground floor, the total area of all other floors must be between 750 sq.cm and 950 sq.cm at a scale of 1:100 from real building.}
my doubt: this floor area restriction of all floors as 750 to 950 sq.cm at scale of 1:100 is whether complied with model or real building. as you mentioned we can represent 3 floors of a real building as a single floor in the model
 Adam Crewe posted on Thursday, August 12, 2010 - 02:25 pm
In the MODEL building the total area of all the floors (excluding the ground floor) must be 750-950cm2. However you will only be building every 3rd floor relative to the REAL building.

For example, if I assume you have 3 floors above ground in the model (each 250cm2 with total area 3x250=750cm2), the real building would have 9 floors above ground (each floor 250m2 giving a total area in the real building of 9x250=2250m2).

It is critical that the floor areas in the MODEL obey the competition rules for the structural model, the toal floor area in the real building will then depend on the structural shape of the building.

Just make sure you get the rules for the model building correct and then make sure the architecture matches your structural frame.

Remember you don't need to plan the floor layouts in the real building you only need to decide on the overall architectural form.
 R Manoj posted on Saturday, August 14, 2010 - 04:38 am
If we are designing our building columns with steel I sections, is it compulsory that the area of steel sections used for the building design should be in equal scale (or reduced) with that of the section (6mm x 4mm) used for the model ???
 Wendy Daniell posted on Saturday, August 14, 2010 - 11:36 am
No, don't worry about exact scaling for the members of your model. The model only has to be representative of the real structure i.e. the same shape and with similar bracing and beam and column arrangements.
 R Manoj posted on Saturday, August 14, 2010 - 01:36 pm
Thank you
 G. Krishnakumar posted on Tuesday, August 17, 2010 - 10:51 am
Since we have to provide around 2.5 kg load per floor, will any buckling of columns be observed and do we have to provide any structural modifications for the same?
 Adam Crewe posted on Tuesday, August 17, 2010 - 11:15 am
If the columns are too long and/or too slender then yes there is a possibility of buckling. You could always do some load testing of some actual MDF sticks to see what their capacity is.
 G. Krishnakumar posted on Wednesday, August 18, 2010 - 06:55 am
By adopting the length as 8cm per side, the weight is calculated aS 3090g, for which approximately 5 blocks(4.88 blocks) are calculated as per rule 1 in serial no. 6 of model specification brief. So we reduce the dimension to 7.5cm, therefore the no. of blocks is calculated as 4.27 blocks. The question we would like to ask is whether this 4.27 would be taken as 5 blocks or 4 blocks?
 Wendy Daniell posted on Wednesday, August 18, 2010 - 11:13 am
If you have a square floor with 8cm sides, then the floor area is 64sq cm and the total mass required is 640 grams (i.e. 10g per sq cm). Each block weighs 635 grams, so this area would only require 1 steel block. Either you have given me the wrong numbers or you have misunderstood the rules for the vertical load. Check them at http://www.ideers.bris.ac.uk/dynamicdesigns/vertload.html.

However in answer to your question, if you calculate that you need 4.27 blocks then you will have to have 5 blocks placed on the floor.
 Ahmad Wani posted on Thursday, August 19, 2010 - 09:38 am
i wanted to confirm one thing.. i've been told that the structure will be tested without the steel blocks, in the beginning, and then the steel blocks would be loaded onto it. are we allowed to tie the sets of steel blocks (for each floor) together, before they being loaded onto the model, instead of them being loaded one by one?
 Wendy Daniell posted on Thursday, August 19, 2010 - 11:32 am
What we will do at the final is first to check that all constructucted models obey the rules (that may be what you think the testing without steel blocks means). The models will then be fixed to the shaking-table and the steel blocks will be added afterwards. We don't know whether the teams will be allowed on to the shaking-table to add the blocks or to do any final fixing of the blocks. This means that you should not plan to tie the sets of steel blocks together as this would be difficult for someone else to handle. You can however design your fixings for each floor for each set of blocks rather than one fixing for one block. I would recommend that use the MDF strips for your fixings as they will hold the blocks firmly in place. String will loosen during the shaking and then your blocks would fall out of the building and the model will then be judged to have failed.

I hope this helps.
 S. Mohanroop posted on Thursday, August 19, 2010 - 04:10 pm
we have decided to give 2 MDF stick as columns for our lower floors but since we are allowed to drill only holes of diameter 8 mm . . is it possible to use the double MDF sticks?
 Adam Crewe posted on Thursday, August 19, 2010 - 04:33 pm
You can still double up the MDF sticks to make the columns stronger but just leave 1 stick 6mm longer than the other to allow the longer one to go into the hole in the baseboard. This will give a strong column and a good base board connection.
 Harshini Sampathkumar posted on Thursday, August 19, 2010 - 07:31 pm
Hi, in the model photos given in the specification what material has been used for the floors?

I mean the white canvas kind of material representing the floor plate.

Please advice. and if its a4 paper, what GSM would it be of?
 G. Krishnakumar posted on Friday, August 20, 2010 - 09:16 am
We have not found the structural usage for the A4 sheets in our model yet, does the A4 sheets perform any specific function if its used in our model?
 Wendy Daniell posted on Friday, August 20, 2010 - 10:12 am
The photos in the specification show paper covering for the floor. This paper is just normal printer paper of about 80 gsm cut from an A4 sheet. Similar weight paper will be provided at the final.

Paper can be used structurally and works well in tension as long as you ensure good connections (with glue) to columns and beams. Here are some examples of how you can use paper.

1. As tension braces - you can fold and glue paper to make thicker members.
2. As walls - not shear walls but tension walls. Make sure that all four sides of the paper are glued along the whole length to the columns and beams and the paper wall work very effectively.
3. To give floors torsional stifness - if you glue paper at the edges to a square made from mdf strips, the paper acts as bracing to stop the floor distorting in plane.

There are other uses for paper too. Just use your imagination.
 Palaksha Krishna Shetty posted on Tuesday, August 24, 2010 - 07:08 am
can we have a tapered top of the building and if so will this be considered as a slab and applied weight on it.
 Wendy Daniell posted on Tuesday, August 24, 2010 - 08:28 am
You can have a tapered top to your building. If it comes to a point at the top, that will not be considered as a slab. If it tapers up to a flat roof, then the flat roof will be considered as a slab and it wil be loaded. Remember you still need at least 4 flat floors - the ground floor and the 1st, 2nd an 3rd floors.
 Jaykrishnan A posted on Tuesday, August 24, 2010 - 08:35 am
HI,

is there any incentive for reducing the budget?..
 Adam Crewe posted on Tuesday, August 24, 2010 - 09:08 am
At the final we will be awarding prizes for:

The Best Presentation
The Most-efficient model
and The Overall winner

If you want to be in with a chance at for Most-efficient model and probably the overall winner prizes your building needs to "efficiently" survive the earthquakes. See the model spec for exactly how efficiency will be calculated, but lowering the cost will improve the building efficiency (assuming it survives the same earthquake) i.e. don’t include unnecessary material.
 S. Mohanroop posted on Sunday, August 29, 2010 - 04:32 pm
Hi,
we would like to do some design calculations for our model for which we require certain values of the material properties of the MDF like

1. MDF's Young's modulus (E)
2. MDF's Poisson's Ratio
3. MDF's Density

It would be great if you can provide us these values.
 S. Mohanroop posted on Wednesday, September 08, 2010 - 04:16 am
Hi,
We have introduced reinforcements with the MDF sticks on the ground floor as plinth beams for our model as we feel the points where the columns are fixed to the MDF board are weak points, but we are not sure if we are breaking any rules by doing so, can you please guide us.
 Wendy Daniell posted on Monday, September 13, 2010 - 11:07 am
The MDF will have a density of 760-780 kg/m3.

Typical values for the Modulus of Elasticity are 2.5 GPa -5.0 GPa. We don't know the exact value for the MDF that will be used, but you don't really need to be that exact.

We don't have values for Poisson's ratio but you may be able to find some typical vlaues with a web search.
 Wendy Daniell posted on Monday, September 13, 2010 - 11:11 am
Regarding the plinth beams on the ground floor - if you use these you must still ensure that you have 15cm clear height between the top of the plinth and the underside of the floor structure for the 1st floor.

If you think the column connection to the the base is a weak point, have you thought of either drilling holes in the base board so that you can glue the bottom of your columns into the holes, or even using string somehow to tie the columns down.
 Jaykrishnan A posted on Sunday, September 19, 2010 - 10:26 am
Hi,

You have mentioned that the steel blocks (vertical load) will be placed after you have checked that the model isnt breaking any rules.

However, the bracing of our structure doesnt allow for placing the blocks afterwards...its a pretty closed design...especially for lower floors.
Kindly advice.

Regards,

Quake Factor- Team 23
 Wendy Daniell posted on Sunday, September 19, 2010 - 02:20 pm
Hi Team 23

I am afraid that you will need to alter your bracing slightly or the position for your blocks.
 MAHESH BABU ADDALA posted on Sunday, September 19, 2010 - 07:49 pm
Dear Sir
The fixture arrangement we have thought of projects well beyond the floor level. Can we tie the upper part of the fixture to the
columns in that storey?

Regards
DEQ Team-4
 Wendy Daniell posted on Sunday, September 19, 2010 - 08:43 pm
Hi Team 4

A sketch would help me understand what you are trying to ask. Can you upload one for me?
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