precaster stuff Flashcards
what are the 5 products
hollow core double tees flat slab rib and infill shell beams
flat slab advantage
cost effective for short spans
good acoustric and fire rating
flat slab drawbacks
requires propping past 2.5 m
heavy floor system
Rib and infill Advantages
lightest
prestressed with timber infills
cost effective fro short to medium
flexibnle
drawbacks of rib and infill
requires propping
double tees advantagers
good for carparks
long spans
unporpped
2.4 m width, less crane movement, less install time
hollow coreadvatnages
extruded product, produce a lot quickly doesnt require propping cost effective for long spans good acoustic thinnest long span
summary of whats best for short to medium
flat slab
rib and infill
whats best for ling
hollow core
double tees
3 options for designing
1 precasters design the shell and formwork, consulting does everything else
2 consulting provides loads, precaster designs units
3 consulter provides all loads, pre caster takes design responisbility for whole unit
strength of precast unit and of topping
50 precast
25 topping
what strenght strand used in christchurch for default, double tees/hollow core, and bridges
138 kn default
184 Kn hollow core
250 Kn, Bridges
minimum seatring
75 mm
