{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

ARC322 Homework 16 SOLUTION 2008

# ARC322 Homework 16 SOLUTION 2008 - 2(includes joist DL...

This preview shows pages 1–2. Sign up to view the full content.

ARC322 Homework 16 12 Points SOLUTION 1. A building measures 40 ft by 100 ft. It carries a DL = 35 lb/ft 2 (w/o joist DL) Tributary 35 lb/ft 2 x 5 ft = 175 lb/ft It carries a LL = 20 lb/ft 2 Tributary 20 lb/ft 2 x 5 ft = 100 lb/ft The joists are spaced at 5 ft OC Select the most economical open web joist Drawing 2 Points Uniform Load each joist = 55 lb/ft 2 x 5 ft = 275 lb/ft 24K9 will carry 304 LB/FT – 12 LB/FT = 292 LB/FT > 275 LB/FT … OK 2 Points Deflection Calculation 24K9 175 lb/ft – 12 lb/ft = 163 lb/ft > 100 lb/ft . .. OK 2 points NOTE … If they selected a 24K4 or a 24K6 … they just barely makes it … so, they are OK by code … but a better selection is the 24K9 which will reduce “bounce”. 2. A building measures 36 ft x 300 ft It carries a DL = 45 lb/ft

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 2 (includes joist DL) Tributary 292.5 lb/ft – It carries a LL = 15 lb/ft 2 Tributary 97.5 lb/ft – Joists are spaced at 6.5 ft OC – Select the most economical open web joist – NOTE: We do not need to reduce the joist load since the problem statement tells us that the Roof DL includes the weight of the joist. Drawing 2 points Uniform Load each joist = 60 lb/ft 2 x 6.5 ft = 390 lb/ft 26K9 will carry 409 LB/FT = 409 LB/FT > 390 LB/FT … OK 2 points Deflection This is the minimum drawing allowed. If they did better drawings, such as showing the tributary loads, give 1 point EC on each one problem. 26K9 will carry 284 lb/ft > 97.5 lb/ft … OK 2 Points NOTE … If they selected a 30K7 I only weighs 0.1 lb/ft more … so OK...
View Full Document

{[ snackBarMessage ]}

### Page1 / 2

ARC322 Homework 16 SOLUTION 2008 - 2(includes joist DL...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online