Structural Design Process.pdf

START Project

Owner

SM, AYALA Land, Robinson's, Waltermart, etc.

Project Overview

Chief Structural Engr.

Owner Requirements, Design approach and Timeline

Structural System

Framing Layout

Structural Engr.

Layout Structural Frame

Chief Structural Engr.

Approval of Framing Layout

Design Criteria

Structural Engr.

Code Requirements (NSCP 2010)

DL, LL, WL, EQL, etc. (NSCP 201 Sect. 2)

Chief Structural Engr.

Model [ETABS, STAAD, SAP, SAFE, etc.]

Eng'g Judgement re. the analysis output

Discussion with Chief Structural Engr.

Chief Structural Engr.

SPI-Structural Performance Index (Estimate Ratio)

Chief Structural Engr.

Spot Check of the design

Approval of SPI

Accomplish Process Checklist (Att. 3)

Relay design to CADD Designer

Check Print (2 Levels)

Chief Structural Engr.

Pre-final Check Print

Approval of drawings

Mathematical

Model

Structural Engr.

Structural Element Design

Structural Engr.

Structural Drawings

Structural Engr.

Production of Structural Drawings

CADD Designer & Structural Engr.

Sorting of Plans

Structural Calculations & Specifications

Structural Engr.

Accomplish ST Calculations & Specifications

Transmittal Form

Structural Engr.

FINISH

Software generated or ECC Spreadsheet (Att. 2)

Accomplish Drawing Index Checklist (Att. 4)

Prepare Transmittal Form (Att. 5)

(NSCP 2010 Table 208-11)

Submit Drawing Index Checklist to Chief Structural Engr.

Relay to CADD Designer

Approval of Design Criteria (Att. 1)

Approval of mathematical model which corresponds to structurally sound analysis output

Structural Head

Final Check Print and Approval of drawings

Project It is a work awarded by our clients to perform structural design/investigation/peer review of a certain structure/s in a specific location. Project Overview The general background of the project which describes about client’s requirement, design approach and timeline. Structural Framing Layout Denote and locate the arrangement of structural members in floors and roofs of a structure. Design Criteria It is the overall structural design requirements of a building which include design loadings. Such loadings are Dead load, Super-imposed Dead loads, Live load, Wind load, Earthquake load, etc. Mathematical Model Idealization of structure by the aid of using structural design software/s (ETABS, STAAD Pro, SAP2000, SAFE, etc.) which will be simulated with the given appropriate design loadings. Structural Element Design Individual design of structural members that comprise the whole structure, such design manifest sufficient concrete section, number of reinforcing bars and necessary detailing under a given demand of loadings. Structural Drawings Visual representation on how a building or other structure will be built. It outlines the frame, size and types of materials to be used, as well as the general demands for connections in relation to structural element design. Production of Structural Drawings Set of drawings managed by CADD specialist with the supervision of Structural Engineer. Structural Calculations & Specifications These are the compilation of documents that represent the theoretical calculation of structural drawings, and technical specifications that will serve as guide during project execution. It is usually handled by Structural Engineer and approved by the Chief Structural Engineer. Transmittal Form It is generally accomplish when transmitting a certain document prepared by the assigned CADD Specialist/Structural Engr./Chief Structural Engr.

STRUCTURAL DESIGN CHECKLIST Project Code Project Title

: :

Item No. 1.0 1.1 1.2 1.3

TABLE OF CONTENTS Input Data Output Data Summary

2.0 2.1 2.1.1 2.1.2 2.1.3 2.1.4 2.2 2.2.1 2.2.2 2.2.3 2.2.4 2.2.5 2.2.6 2.3 2.3.1 2.3.2 2.3.3

INPUT DATA DESIGN CRITERIA Strength of Materials Soil Bearing Capacity Loadings Code References LOADINGS Dead Load Live Load Wind Load Seismic Load Equipment Load Others COMPUTER MODEL Graphics Member Numbers Node Numbers & Coodinates

3.0 3.1 3.1.1 3.1.2 3.1.3 3.1.4 3.2 3.2.1 3.2.2 3.2.3 3.2.4 3.2.5 3.2.6 3.2.7 3.2.8 3.2.9 3.2.10 3.2.11

OUTPUT DATA ANALYSIS RESULTS Member Stresses Support Reactions Drift Requirements Deflection Requirements DESIGN RESULTS Foundation/Column Footings/Wall Footings Columns/Pedestals Beams/Girders Suspended Slab Slab on Grade Wall Trusses Rafters Floor Joist Purlins Connections

4.0 4.1 4.2 Legend: CSE SE TA

DESCRIPTION

SUMMARY Detail of Members Detail of Connections

-

Chief Structural Engineer Structural Engineer Technical Auditor

SE

CSE

TA

Remarks

ECC ETABS Design Checklist A. Loads and Forces 1. Check superimposed dead loads(floor finishes, ME Utilities, Ceiling etc.) for every floor as per architectural drawings. 2. Check superimposed wall (Internal Partitions) dead loads for every floor as per architectural drawings. Wall (Internal Partitions) loads must be calculated and converted to floor pressure loads. Such wall must be resting on top of slab. 3. Check superimposed live loads for typical floors as per architectural drawings. 4. Check superimposed roof live loads for roof as per architectural drawings. 5. Exposure coefficients for wind definition must be Exposure from extents of Rigid Diaphragms. 6. Check for wall (directly resting on beams) loads for every floor as per architectural drawings. 7. Check for concentrated loads if deemed required. 8. Check for roll up doors, accordion doors and main door arches possible for additional load. 9. Verify architectural planter requirements. (Soil thickness and waterproofing) B. Modeling 1. Check levels based on design drawings. (Use actual TOSS) 2. Gridlines should match the design drawings. (Define main gridlines) 3. Check slab sizes and orientation based on design drawings. 4. Check column based on design drawings. 5. Check beam based on design drawings. 6. Check RC walls length based on design drawings. 7. Diaphragm should be rigid for precast/cast-in-place structural concrete slab. For precast, min. of 65mm concrete topping to be considered as rigid. Stair and opening should not be considered as diaphragm. 8. Check if there's a coupling beam above the opening of shear wall. 9. All slab main openings shall be modelled. 10. Check plan view. Beam should not be column design. 11. Check planted column/s resting on concrete elements. It must be modelled as fixed connection. C. Parameters and Constants 1. Check material properties. Ec = 4700*(F'c)^0.5, gc = 23.56 kN/cu.m., Reinf fy = 414 MPa (Grade 60), Reinf fy = 276 MPa (Grade 40) 2. Check gravity static loads cases. Weight Factor for sta c load cases: For Machinery Loads refer to NSCP 2010 Sec. 206.3.2 3. Check seismic load cases EQXPE, EQYPE and EQXNE, EQYNE with eccentricity ratio of 0.05 + and - direction, respectively. 4. Check generated 2 wind load cases along 0 and 90 wind direction angle. 5. Column modifier : M2 = 0.70, M3 = 0.7, T =1 6. Beam modifier : M2 = 0.35, M3 = 0.35. For perimeter beams T = 0.1, interior beams T=0.01 and T=1 for beams with significant torsion 8. Slab modifier bending: mm11 = 0.25, mm22 = 0.25, mm12 =0.25 (If the modeled slab is shell type) 9. Wall modifiers: f11=0.35,f22=0.35 (cracked section); f11=0.70,f22=0.70 (uncracked section). For mm11 and mm22 it varies. 10. Shear wall should be assigned as pier. 11. The values for period parameters; concrete moment resisting frames and eccentrically braced frames 0.030. Steel moment resisting frame 0.035 and all other structure 0.02. 12. All wall types should be assigned as shell. Flat slab system must be shell, and other slabs are Membrane. 13. Check load combination for shear wall. (As per ACI 318-08/NSCP 2010) 14. Check load combinations for concrete under given design code. (As per ACI 318-08/NSCP 2010) 15. Check load combinations for steel under given design code. (AISC ASD/LRFD) 16. Add service load to all combinations. (As per ACI 318-08/NSCP 2010[Alternate Basic Load Combinations]) D. Analysis Options 1. Remove dynamic analysis from option for regular structures and for structures under design category A. 2. Consider dynamic analysis for Irregular structure or for structures that fall under the category of implementing Dynamic analysis. Number of modes = 3*No. storey; Type of analysis is Ritz Vectors; Ritz Load Vectors are Accel X and Y. Afterwards, do the base shear scaling. E. Warnings 1. Check unconnected elements using the deformed shape view. 2. Remove warning from analyze/check model. Check all boxes. 3. Resolve warning/s from Analysis Run Log. F. Analysis Output 1. Check Modes 1, 2 and 3 deformation shape. (For dynamic analysis) 2. Ideal period for low to mid rise structure is 0-5sec. For high rise structure 5-10sec. (For dynamic analysis) 3. Check drift limits. Refer to NSCP 2010 Sec. 208.5.10 G. Design Output 1. Check RC column design in ETABS to satisfy joint shear capacity and strong column-weak beam action. The designer may opt to use column shear check capacity and strong column-weak beam action spreadsheet. 2. Check RC beam design in ETABS and reinforcement of such should be performed by seismic beam design spreadsheet. Limit red colored in ETABS output. As well as consider shear and torsion in beams. 3. Check RC wall design as per ACI318-08. 4. Check steel design as per AISC ASD/LRFD.