Transitional TentsJohannes Whittam (University of Cambridge)

Transitional Tents Contents

• Introduction & Background

• Calculations and Modeling

• Testing & Results

• Failure

• 6 Conclusions

• 2 Areas for Further Work

• Questions

Transitional Tents

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Previous Work

2000 – Assessing the Thermal Performance of an Emergency Shelter (C A Crawford)

2001 – Thermal Performance of a liner for a UNHCR tent (R Battilana)

2003 – Investigation into Heat Loss in Cold Climate Emergency Shelters: Development of an Occupancy Model and Infiltration Testing (C Grisaffi)

2003 – Ground effects on Thermal Performance of a Transitional Tent(R Youlten)

2004 – Specificaitons and Design of a Transitional Tent(A Pepper)

2005 – Design and Analysis of an Unbraced Portal Frame Transitional Tent (H Travers)

2007 – Field Investigation, Design and Analysis of a Braced Portal Frame Transitional Tent (M Moynihan)

2008 – Cold Climate Temporary Shelter (M Segar)

Transitional Tents Procurement Specification

A procurement specification for a Transitional Tent was produced by Shelter Centre for DFID by the end of 2011.

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Modeling

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Modeling

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Modeling

The addition of lightweight sheeting reduces the forces applied to the frame as it eliminates this effect.

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Testing

• Introduction

• Calculations &

Modeling

• Testing &

Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Testing

• Introduction

• Calculations &

Modeling

• Testing &

Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Testing

• Introduction

• Calculations &

Modeling

• Testing &

Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Testing

Strain

Gauges

Inclinomet

er Battery

Packs

Inclinomet

ers

Inclinomet

er Bracket

Inclinomet

er

Transmissi

on Units

• Introduction

• Calculations &

Modeling

• Testing &

Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Testing

Inflated Bag

Data Logger

and Laptop

(Inclinometer

Output)

Strain

Gauges &

Inclinometers

(inside)

Tube for pressure

reading

• Introduction

• Calculations &

Modeling

• Testing &

Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Results

• Introduction

• Calculations &

Modeling

• Testing &

Results

• Failure

• 6 Conclusions

• Further Work

• Questions

2 3 4 5 6 7 8 9 10 11 12

-10

-9

-8

-7

-6

-5

-4

-3

-2

-1

0

Sandbags On, Bracing Not Fully Tight, Full Fan SpeedSandbags On, Bracing Not Fully Tight, Half Fan SpeedSandbags On, Bracing Fully Tight, Full Fan SpeedSandbags On, Bracing Fully Tight, Half Fan SpeedSandbags On, Bracing Removed, Full Fan SpeedSandbags Removed, Bracing On Fully Tight, Full Fan SpeedSandbags Removed, Bracing Removed, Full Fan SpeedSandbags Removed, Bracing Removed, Half Fan SpeedSandbags On, Bracing Removed, Half Fan Speed

Fresultant,x (N)

Fre

sult

ant,

y (

N)

Scatter Plot of Forces for Fan Test (Fresultant,x vs Fresultant,y)

Transitional Tents Results

Eave should buckle at 25ms-1

Force 9 on the Beaufort ScaleThis is not the most critical failure mode – uplift is

• Introduction

• Calculations &

Modeling

• Testing &

Results

• Failure

• 6 Conclusions

• Further Work

• Questions 0 2 4 6 8 10 12 14 160

2

4

6

8

10

12

14

f(x) = 0.339660922955922 x

Scatter Graph of Wind Pressure vs Fresultant

Pressure (Pa)

Fre

sult

ant

(N)

Transitional Tents Failure

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Failure

Failure 1

Failure 2

Wind

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Failure 1

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Failure 2

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Recommendations/Improvements

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

① Porch② Floor Beams③ Bracing

- Coming Undone- Both Bays

④ Hole Alignment⑤ Joining Method⑥ Peg Loops

Transitional Tents Recommendations/Improvements

Porch and cavity

significantly increase uplift

forces

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Recommendations/Improvements

① Porch② Floor Beams③ Bracing

- Coming Undone- Both Bays

④ Hole Alignment⑤ Joining Method⑥ Peg Loops

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents

(Please Find the video attached on the shelter Centre website where this presentation was found)

Recommendations/Improvements – Floor Beams

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional TentsRecommendations/Improvements – Floor Beams

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Recommendations/Improvements

① Porch② Floor Beams③ Bracing

- Coming Undone- Both Bays

④ Hole Alignment⑤ Joining Method⑥ Peg Loops

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Recommendations/Improvements

Existing:

Recommended:

Or, even better:

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Recommendations/Improvements

① Porch② Floor Beams③ Bracing

- Coming Undone- Both Bays

④ Hole Alignment⑤ Joining Method⑥ Peg Loops

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Recommendations/Improvements - Bracing

Transitional Tents Recommendations/Improvements

① Porch② Floor Beams③ Bracing

- Coming Undone- Both Bays

④ Hole Alignment⑤ Joining Method⑥ Peg Loops

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional TentsRecommendations/Improvements – Hole Alignment

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Recommendations/Improvements

① Porch② Floor Beams③ Bracing

- Coming Undone- Both Bays

④ Hole Alignment⑤ Joining Method⑥ Peg Loops

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional TentsRecommendations/Improvements – Joining Method

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Recommendations/Improvements

① Porch② Floor Beams③ Bracing

- Coming Undone- Both Bays

④ Hole Alignment⑤ Joining Method⑥ Peg Loops

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Recommendations/Improvements – Peg Loops

Transitional Tents Further Work

Future students from Cambridge

University Engineering

Department will continue the

project.

Foundation Design

Further Testing

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Transitional Tents Questions

Conclusions:① Porch② Floor Beams③ Bracing

- Coming Undone

- Both Bays④ Hole Alignment⑤ Joining Method⑥ Peg Loops

• Introduction

• Calculations &

Modeling

• Testing & Results

• Failure

• 6 Conclusions

• Further Work

• Questions

Tent Rating:25ms-1 provided properly secured

Further Work:- Foundation

Design- Thorough Testing

Questions?