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Design & Construction of Earthquake Resilient Schools
Common Design Errors & Omissions
Government of Nepal Ministry of EducationCentral Level Project Implementation Unit (CLPIU)
Alec Gray & Ishwary Prasad Kharel
GENERAL
Nepal Building Code issues
Seismic Design Code NBC105: 1994
……..compare with………
Mandatory Rules of Thumb/Guidelines NBC 201 to 205
NBC105 and NBC 110 are for Engineers. The MRT/Guidelines are pre engineered
Structural details are only shown in NBC 201 to 205
Not a single design refers the NBC 110 for Designof concrete structure. Noteworthy is that thisstandards rejects any amendment/revision on IS456 -1978 onwards.
(IS4326-IS 1893 part-1-IS 13920-IS 456)
As per IS 1893(Part 1) Importance factor for school
buildings should be 1.5.
DoE Structural Criteria-Schools are Public Buildings: Higher standards
apply
Many designers apparently do not read this document!
Design Reports often lack critical information.
•Poor documentation indicates poor design
•Design Calculation for some critical condition.
•Uplift and overturning for lateral and wind load.
•Site information and hazard mapping as per NBC
108.
•Sanitary and electrical drawings.
•Other environmental and safety concern.
Design submissions often disregard the CLPIU
checklists.
CONCRETE
Starter bars from columns into horizontal RC bands
Not shown nor included in the Steel Bending Chart
RC bands for infill masonry walls
Not shown
•RC bands in end walls: Often missing or shown at
only ½ wall height: They must be at both 1/3 and
2/3 wall height.
•RC band on top of parapet wall: Often not shown
as reinforced and the rebar often not detailed
correctly at the corners.
•Gable ends with masonry infill: RC band enclosing
the gable end often missing.
•RC Band at top of cross wall: often missing.
STEEL FRAME AND ROOF TRUSS DESIGNRoof truss Holding Down (HD) bolt arrangement
Not shown.Diagonal wind bracing
Not shown.
Weld sizes & steel
protection treatment
Not shown.
Steel frame section sizes
Not shown or use incorrect or section
reference
LOAD BEARING MASONRY
RC bands at sill, lintel and eaves level
Stitch bands at corners not shown.
Not shown. See NBC 202 Load Bearing Masonry
Vertical steel reinforcing through masonry at
corners, intersecting walls, and wall ends.
Not shown.
Type of masonryNote: dressed stone masonry is preferred by DoE
Not shown
Connection of masonry infill walls to steel
frames
Method of connection: Not shown
QUESTIONS?
Thank you
