I.S. 255:1983

Declaration
Foreword
1 Scope
2 Definitions
   2.1 Basic module
   2.2 Characteristic strength
   2.3 Component
   2.4 Co-ordinating dimension
   2.5 Co-ordinating size
   2.6 Deviation
   2.7 Modular co-ordination
   2.8 Work size
3 Materials
   3.1 Cement
   3.2 Aggregates
   3.3 Water
   3.4 Additives or admixtures
   3.5 Reinforcement
   3.6 Care and cleanliness of reinforcement
   3.7 The use of materials
4 Length of lintels
   4.1 Co-ordinating length
   4.2 Work size length
   4.3 Non-modular lengths
   4.4 Preferred lengths
5 Cross-section of lintels
   5.1 Co-ordinating widths (thickness)
   5.2 Co-ordinating height
   5.3 Permitted deviations
6 Bow or twist
   6.1 Bow or twist
   6.2 Method of measuring bow or twist
7 General
   7.1 Moulds
   7.2 Finish
   7.3 Casting
   7.4 Freedom from defects
   7.5 Throating
8 Concrete
   8.1 Testing
   8.2 Concrete strength
   8.3 Low temperature
   8.4 Curing of concrete
   8.5 Durability
   8.6 Time of delivery
9 Steel
   9.1 Main (bottom) steel
   9.2 Top steel
10 Inserts
11 Performance requirements
   11.1 Load-bearing strength
   11.2 Testing
   11.3 Proof test
12 Quality control
   12.1 Records
   12.2 Load-bearing test
   12.3 Testing procedure
13 Verification of compliance
14 Information for users
15 Marking and ordering
APPENDICES
A Load testing
B Reference standards
ACKNOWLEDGEMENT

Gives requirements for precast reinforced concrete lintels suitable for use over doors and windows.