BUILDING MAINTENANCE PROBLEMS & SOLUTIONSBy M. C. Paliwal NITTTR Bhopal

Q. What is the similarity ?

Objectives:

1. Develop awareness about the health problems of R.C.C. components of buildings

2. Classify various causes of deterioration

3. Explain various types of deterioration

4. Suggest preventive measures for long life of buildings.

Q. Why there is Need for Building Maintenance? To strengthen its weaker members & lengthen its life.

Q. Classify the types of Defects in building:- Macro defects: Visible from naked eye-Micro defects: Not visible from naked eye

Q. What are the causes for deterioration of RCC buildings?

Poor structural design and specificationsPoor quality of constructionPoor maintenance of buildings Environmental problems and aging effectsIndiscriminate additions & alterationsNatural & manmade calamity

1.Poor structural design & specifications-Densely spaced steel bars-Segregated concrete at beam column junction-Honey combing of concrete

2.Poor construction & overloadingwith illegal mezzanine floors

Poor Construction, Poor quality of materials used & poor supervision.

-Poor construction & neglected maintenance

Check for materials like cement,sand admixtures etc.-Proper mixing and batching of materials

cSilt & clay in sand

Excess water in mortar

3.Poor maintenance -Leaking roof -Spalling of Concrete due to corrosion

-Preventing Vegetative growth on Buildings

- Collapse during Extension work - Collapse during Modification,Renovation

4- Environmental Conditions around the Buildings,Chemicals like carbon-dioxide, chlorides, nitrous oxides, moisture and sulphates

5- Overloading of structure or Weakening its structural members due to alteration/ renovation.

Weakening the Structure by Chipping of Concrete and Removing Reinforcement SteelWeakening the Structure in Stilt Portion (Parking Area) of the building

.-Proper supporting,propping for load carrying members

-Chipping of defective or deteriorated concrete

Proper packing of mortar between RCC beams,columns and brick masonry

Repairs by guniting/jacketingwith concrete or treated with cement or polymer concreteRoughened base coat of plaster for better mechanical bond with the finishing coat.

Curing by ponding water on horizontal surface

Curing by spraying water at regular intervals on vertical surface

To reduce cost :Check the locations where repairs are necessary and where repairs need not be done.Whole plaster is replaced.Removal of rust before repair using guniting

Rusting of steel in RCC column on ground floor resulting in spalling of concreteCracks,crevics ,joints and junctions should be properly packed before repairs.

Cracks developed due to improper curing.Failure due to modification

Building before repairs and after repairs

Corrosion of steel & spalling of concretedue to ingress of moisture

-Cantilever canopy showing porous honeycombed concrete

-Deteriorated cantilever balcony slabs

Spalled concrete due to corrosion of steelby leakage

- Cracks over superficially repaired surface

- Corrosion of steel in RCC beam

5.Indiscriminate Addition & Alterations in BuildingsSome DOS & DONTSAlterations in Window balcony

Additions to window canopy

Conversion of balcony into dressing room

Conversion of balcony into a bath room

Adding waterfall & potted plants on balcony

Overloading the RCC building by installing large tanksBefore After

Careless modification causing damage to structure

Damaging RCC beam to conceal electric conduits & adding load by new floor tiles

Chamfering RCC columns in stilt area toavoid damage to cars

Removing RCC beams & columns between two flats

Removing RCC beam and part of RCC slab & Introducing additional staircase load to interconnect two flats

Introducing additional load on RCC slab & beam by relocating partition wall

6.Natural calamities of building failure-Earthquake-Floods-Terrorist attack-Bomb blast

Conclusion: How to increase life of any building?

To prevent deterioration of R.C.C. buildings proper measures are required in following steps.

1.Proper structural design and specifications2.Proper Construction practices 3.Timely Preventive Maintenance4.Check indiscriminate additions & alterations5.Safety for natural & manmade calamity

Treat the old building as hospitalised human being.

-Engineers/Consultants are like Physicians.

-Contractors are like surgeons.

-Occupants are like relatives of the building.

So timely action is very important for the long life of buildings.