We were requested to proposed a solution for timber beam failure when we visited a site visit.

1. TIMBER BEAM FAILURE
(CONSTRUCTION MATERIALS)
INSTRUCTED BY:-
Miss .KGA KARIAWASAM
GROUP MEMBERS:-
1. RASATH. MNM 62
2. SAFEER. SAM 68

2. LEARNING OUTCOMES
■ To identify the methods of detection of compression failures in timber
■ To know the behavior of the wooden beam subjected to bending
■ Failure mechanism of timber
■ Repairing timber and replacing damaged section by reinforcement

3. INTRODUCTION
• Detection of timber beam failure
• Methodology
• Analyzing the problem
• Proposed solution

4. INTRODUCTION….
■ Timber is an excellent material for the load-bearing components for
large buildings and for their challenging roof structures with long spans
■ If a timber beam is loaded too heavily it will break or fail in some
characteristic manner
■ These failures may be classified according to the way in which they
develop, as tension, compression, and horizontal shear; and according
to the appearance of the broken surface, as brash, and fibrous

5. DETECTION OF COMPRESSION FAILURES INWOOD
■ Side grain inspection :-
Look along the smooth surface of a piece, with the light striking
along the grain at an angle of about 20° with the surface.The point of view
should be varied between 45° and vertical, on the same side of vertical as
the light source

6. METHODOLOGY
■ The damaged timber beams were observed on 2018.11.03 at old market
building, sammanthurai
Data collection
1. Primary data:- Site observation
2. Secondary data:- Website ,Books and researched magazines
■ In the site the roof structure was carried by the timber trusses. Some
timber beams were failed in tension and compression.The damaged
beam sections were observed and identified the failure type
■ In this report, some solutions will be proposed for the damaged parts
using reinforcement

7. ANALYSINGTHE PROBLEM
■ Tensile strength of wood is on the average about three times as great as
the compressive strength
■ Beam starts to fail on the compression side due to the crushing action, then
follows by failure on the tension side

8. ■ Failure types of beam in tension.
(a) splintering tension (d) brittle tension
(b) combined tension and shear
(c) shear
(b) combined tension and shear
• Identified failure -1

9.  Failure types of beam in bending
(a) simple tension (d) brash tension
(b) cross-grain tension (e) compression
(c) splintering tension (f) horizontal shear
• Identified failure -2
(b) cross-grain tension (a) simple tension
• Identified failure -3

10. PROPOSED SOLUTION
Composite rod anchored With resin
1.0) Repairing timber and replacing damaged sections.
•Reconnect cracked or broken sections by reinforcing them with composite
rods to the area in tension

11. ■ Restructure damaged sections of beams from which material has been
lost, by pouring resin concrete and anchoring tie rods to the sound
sections of the timber
Reinforced resin concrete

12. 2.0) Increasing moment of inertia
Type 1:- From underneath
■ Increase the bending strength and stiffness of a beam by adding a
timber reinforcement to the area in tension.The timber foundation
plate is secured to the existing element with epoxy resin adhesive and
connected using reinforcement bars or composite rods
Additional timber element

13. Type 2:- From above
■ Increase the bending strength and stiffness of a beam by adding a resin
concrete compression flange.This solution has the advantage of not
altering the aesthetics of the underside of the floor.The reinforcing
plate is connected to the beam using resin shear keys and connecting
rods
Additional resin concrete element

14. CONCLUSION
■ In modern world construction industries are facing many challenges due
to the failure of materials. When we use the wood as a beam some time
failures will be occurred by the long time usage . In this presentation
some solutions were discussed by repairing with reinforcement