DESIGN
OF A TWO-LEVEL CONCRETE STRUCTURE
1. Description of Structure and Loading Parameters
This two level concrete structure is located
at the feed end of a kiln in a cement manufacturing plant.
The nominal measurements were: 70' by 45' and 25' in height,
comprised of slabs, beams and columns--for a visual reference
of the framing see to Fig. A. below:
The
live loads on both floors are fairly heavy: on the second
level they are 350 psf and on the first, 275 psf. In addition,
on the first-level beams 101 and 202 there are four point
loads of 12 kips each, indicated by (o). On the LEVEL 1
floor plan, the dotted lines on the left side illustrate
typical floor load distribution to the beams. The structure
is also subjected to earthquake forces in accordance with
the National Building Code of Canada, for V= .15, R=5 and
50% of the live load to be included in the mass for seismic
consideration.
The input commands for AMECO-17 to design the structure
are shown in Fig. B. It took 2 hours to prepare this input.
Member sizes did not have to be given, loads did not have
to be manually calculated, nor did any load cases or combinations
have to be specified. To enable AMECO-17 to design the structure,
only loading parameters, member connectivities and member
spans were required to be entered.
If you wish to familiarize yourself with the basics of
the AMECO-17 input language, it would be helpful to read
the next section. Otherwise, proceed to section 3.
2.
Input Commands see Fig. B
The fifth line: USE CODE NBC-95 LSD invokes the
National Building of Canada and the LSD design method.
LIST ALL requests the listing of all design result
tables. The next command serves to suppress the listing
of envelopes--see also level 1 input, where they are
actually required. Then the input for level 2 is entered,
followed by level 1. All data is given in English
units.
LEVEL 2
DESIGN BEAMS requests beam size selection. USE SLAB
9, FLL 350, SPAN 26 specifies slab 9" thick, floor
live load 350 psf and beam spans 26'. Beam marks are
prefixed with the letter B, columns with a C. Thus,
B401 12-6 101 means that beam 401 supports at 12'-6"
the left end of beam 101.
DESIGN COLS SQ 16 requests size selection starting
with 16"; the length of the column is indicated by
L 12-4 and defines the storey height. Unless indicated
otherwise, this value will be used automatically for
LEVEL 1 as well. ANALYSE COLS requires the input of
column sizes. C3 to 4 301 801 means that columns 3
to 4 support in X-direction B301 and in Y-direction
left ends of B801, B901.
LEVEL 1
Similarly, specific commands are used to incorporate
design criteria; on the second line, B101 LL 2(L 6
p12) applies Live Load and two Point loads of 12 kips
at 6' spacing.
LIST
ENVELOPES AT 10 SECTIONS for beams requests: dead,
live and critical moment, shear and steel area listing
at 10 sections per span.
COMPUTE EQ FORCES NBC V 0.15 R 5 MF 0.5 invokes seismic
force application in X and Y directions. |
PROJECT LTZK
STRUCTURE- KILN FEED
CLIENT- MIRON FRERE LTD
$
USE CODE NBC-95, LSD
LIST ALL
SUPPRESS LIST ENVELOPES
$
LEVEL 2
DESIGN BEAMS
USE SLAB 9, FLL 350,FL PROJ 18, SPAN 26
B101, B201 B301
B401 12-6 101 B402 23-6
B501 12-6 101R B502 16
B801 16 B802 TO 902
DESIGN COLS SQ 16, L 12-4
C3 TO 4 301 801
C6 TO 8 401 201 802
C10 TO 12 501 201R 802R
$
LEVEL 1
DESIGN BEAMS, FLL 275
B101 LL 2(L 6 P 12)
B201 18 OP NS B202 LL 2(L 6 P 12)
B301 18 B302 16-0 201 B303
LIST ENVELOPES AT 10 SECTIONS
B401 18 B402 8 101 8 202 B403 23-6
B501 18 B502 8 101R 8 202R B503 16
B601 18 B602 TO 902
DESIGN COLUMNS
C1 TO 4 301 601 C5 TO 8 401 602
C9 TO 12 501 602R
COMPUTE EQ FORCES NBC V 0.15 R 5 MF .5
EXECUTE
|
Fig.
B
Input
Commands
|
3. Analysis and Design Process
Based on the input commands of Fig. B, AMECO-17 generates
the geometry in 3-D, initializes member sizes, models finite
joints, calculates floor dead and live loads on each member,
calculates seismic forces, sets up loading cases and combinations
and through a cyclical analysis/design process determines
an optimal design for the complete structure (see Fig. C).
This structure was designed in 6 man-hours - from the input
preparation to the review of design results. The AMECO-17
design execution time took a fraction of a second.
Fig.
C
AMECO-17 Cyclical Process
4. Analysis and Design Results
In this section, representative pages are displayed
out of the total of 76 Design Result pages. This design
was done in English units, therefore all member forces and
moments are ftkip units; member cross-section dimensions
and displacements in inches; SI series reinforcing bars
made in Canada are used, as per the NBC code.
The
following results are listed level by level, starting
from the top level.
- Principal
Design Parameters
- Frame
Analysis results for earthquake in X- direction
- Column
Design Tables
- Column
Reinforcing Schedules
- Column
Quantities and Costs
- Beam
Moment, Shear and Steel Envelopes
- Beam
Reinforcing Schedules
- Construction
Costs Summary
- Dayfile
execution time
Use the diagrams on the right to interpret the
reinforcing schedules for beams and columns listed
in
the Design Results tables.
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this page in PDF format. The PDF includes selected
parts of the Design Result Files.
