Lapping and Anchoring of Reinforcements
Knowing the correct lap lengths and anchorage lengths is very very important when reinforcements are detail. In adequate anchorages and lapping has led many failures of structures in the world. This is mainly due to lack of attention to small things that many do not considered as important facts.
According to the BS 8110 Part 01 1997, we can do our detailing in very simple manner without making our life complicated. It has given a simplified table that can be applied to most of the cases. However, when we do specific details, it is better to go head with the first principles rather relay on the simplified table given in the code. Code also provides the method to calculate the bond length requirements. We can use either method for detailing the reinforcements.
Following table can be used to find the lap and anchorage length according to the types of bars are used and the grade of the concrete.
This table is most commonly used by the details due to the simplicity. If we know the types of the reinforcement is used and the grade of the concrete, we can find the lap and anchorage lengths.
For example, assume we are used deformed type 2 bars and grade 30 concrete.
According to the table
Compression anchorage length = 32 times bar diameter
Tension anchorage length = 40 times bar diameter
Similarly, we can find the lap and anchorage lengths from grade 25 to grade 40 concrete.
Knowing the correct lap lengths and anchorage lengths is very very important when reinforcements are detail. In adequate anchorages and lapping has led many failures of structures in the world. This is mainly due to lack of attention to small things that many do not considered as important facts.
According to the BS 8110 Part 01 1997, we can do our detailing in very simple manner without making our life complicated. It has given a simplified table that can be applied to most of the cases. However, when we do specific details, it is better to go head with the first principles rather relay on the simplified table given in the code. Code also provides the method to calculate the bond length requirements. We can use either method for detailing the reinforcements.
Following table can be used to find the lap and anchorage length according to the types of bars are used and the grade of the concrete.
This table is most commonly used by the details due to the simplicity. If we know the types of the reinforcement is used and the grade of the concrete, we can find the lap and anchorage lengths.
For example, assume we are used deformed type 2 bars and grade 30 concrete.
According to the table
Compression anchorage length = 32 times bar diameter
Tension anchorage length = 40 times bar diameter
Similarly, we can find the lap and anchorage lengths from grade 25 to grade 40 concrete.
