Causes and prevention of cracks in buildings

1. A Technical seminarA Technical seminar
OnOn
CAUSES ANDCAUSES AND
PREVENTION OFPREVENTION OF
CRACKS IN BUILDINGSCRACKS IN BUILDINGS

2. CONTENTSCONTENTS
 Introduction
 Causes of cracks
 Detection of cracks
 Conclusion
 References

3. INTRODUCTIONINTRODUCTION
o A crack is a complete or incomplete separation of
concrete into two or more parts, produced by
breaking or fracturing
o An engineer should have a sound knowledge of all
the facts of concrete technology i.e. of the behavior
of construction material, construction techniques,
and types of crack likely to occur, their causes and
respective remedial measure
o Treatment of cracks involves detection, diagnosis
and remedy

4. TYPES OF CRACKSTYPES OF CRACKS
 Structural cracks
-Arise due to various reasons such as incorrect
design, overloading of the structural components,
overloading of the soil on which the building is
constructed or other similar factors
 Non structural cracks
-Arise due to internal forces developed in the
buildings on account of change in the size of
building components, due to moisture variation,
temperature variations, the effect of gases, liquid
and solids on the building components.

5. INVESTIGATION RELATING TOINVESTIGATION RELATING TO
CRACKSCRACKS
The following information helps in diagnosing the cracks:
1. Whether the crack is old or new.
2. Pattern of the cracks.
3. Soil condition, type of foundation used, and movement
of ground if any.
4. Observations on the similar structures in the same
locality.
5. Climatic condition during which the structure has
been constructed .

6. CAUSES FOR THE OCCURANCE OFCAUSES FOR THE OCCURANCE OF
CRACKSCRACKS
o Structural deficiency resulting from design deficiency
or construction deficiency and overloading.
o Temperature and shrinkage effects.
o Cracks due to faulty workmanship and poor
construction practice.
o Cracks due to settlement.

7. Cracks on the column
Cracks around window opening
Horizontal cracks in the middle of wall
Vertical cracks in the middle wall

8. CRACKS DUE TO STRUCTURALCRACKS DUE TO STRUCTURAL
DEFICIENCYDEFICIENCY
-Due to design deficiency
o Cracks occur due to shear, flexural and torsional
steel deficiency.
o Improper anchorage.
o Cracks due to overloading of members
 Figure: Shows a long crack in new wallboard with a width of about an
inch at the corner of the door frame

9.
PREVENTIVE MEASURES:
 Adequate insulating or terracing treatment over
roof slab and by introducing joint between the slab
and the supporting wall.
 Painting top of roof with reflective finish such as
white wash can also minimize cracks.
 Chances of cracking due to temperature variation
can be minimized by introducing expansion,
contraction joints at appropriate locations.

10. CRACKS DUE TO FAULTY WORKMANCRACKS DUE TO FAULTY WORKMAN
SHIP AND POOR CONSTRUCTIONSHIP AND POOR CONSTRUCTION
PRACTICEPRACTICE
Every building process includes a sequence of necessary
step-by-step operation-from conceptual plan to finished
structure Improper column form placement.
Causes:
o Improper bar detailing
o Premature removal of forms
o Cold joints
o Segregation
o Plastic shrinkage cracking
o Improper reinforcing steel placement

12. PREVENTIVE MEASURESPREVENTIVE MEASURES
 By providing proper water cement ratio.
 Proper curing.
 Proper support for forms.
 Following proper design codes and
recommendations

13. CRACK DUE TO SETTLEMENTCRACK DUE TO SETTLEMENT
o Uneven settlement can be a major structural
problem in small residential building
o Loss of moisture
o Soil consolidation under footing
o Water table level
o Occurs early in life of building

14. Fig: Differential settlement caused due to
variable soil type

15. INSTRUMENTS FOR MEASURING
CRACKS IN A STRUCTURE
MEASURING MAGNIFIER
CRACKSCOPE
DIGITAL CRACK GAUGE LOMARO MICROSCOPE

16. INJECTION TECHNIQUE
1. Injections that are used to restore the structural
stability of the structures.
2. Injections that are used to protect the reinforcement
to avoid the moisture and air entering the concrete
thereby lower the rate of corrosion.
3. The injections which are used to stop the water from
entering the structure.

17. CONCLUSION
As for as possible cracks should not
develop in building and care should be taken
that for important & multistoried buildings
,design & execution of building , cracks
should not develop in any circumstances as
cracks affects aesthetics of building & cracks
may cause leaking problems in building.

18. REFERENCES
 Kishor Kunal : “Study on control of cracks in a Structure 2through
Visual Identification & Inspection” IOSR Journal of Mechanical and Civil
Engineering (IOSR-JMCE) e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume
11, Issue 5 Ver. VI (Sep-Oct. 2014
 Rajveer Singh Narwaria : “ Development of cracks in concrete, preventive
measures and treatment methods”: International Research Journal of
Engineering and Technology (IRJET) e-ISSN: 2395 -0056 Volume: 03 Issue: 09
| Sep -2016
 Jailakshmi G Karri et al “Prevention and repair of cracks in building”
International Journal of Research In Science & Engineering Volume: 3 Issue:
2 March-April 2017
 M.A. Jayaram “ Decision Support System for Detecting, Diagnosing and
Suggesting Remedial Measures for Building Cracks” International
Journal of Computer Applications (0975 – 8887) Volume 137 – No.6, March
2016

19. THANK YOU