I checked the strength using the reduced capacity of section 12.2.5 and it works, but is this allowed at a splice location? Are the requirements of 12.2.5 just for straight development length? I have always allowed for reduced capacity of bars at lap splices, but this project might go to the courts. In which case, the required lap splice length is 1.3 x development length but not less than 300mm. In the most common cases, the tension lap is considered Class B. The pier experiences minor uplift and the reinforcement specified is complete overkill(designed by others). To classify a lap as Class A, it must comply with onerous conditions defined in the table below. I am reviewing a project for a client of ours (we didn't do the design for this project) and the dowels for the pier reinforcement only have a splice of around 16". The commentary under 12.15.1 states "The development length ld used to obtain lap length should be based on fy because the splice classifications already reflect any excess reinforcement at the splice location therefore the factor from 12.2.5 for excess As should not be used". The lap splice length for Class A splices is equal to the development length. Linear reduction in the capacity based on the reduced development length. Shear and Moment Diagram for Self-Weight in the Four-Point Setup. The modification factor in 12.2.5 is the As provided/ As req'd reduction. Providing a 3 or larger bar transverse to the lapped bars and within 8 from each end of the lap splice allows the lap splice length to be reduced by the connement reinforcement factor per equation below. Bar ends shall terminate in flat surfaces within 1 1/2 degrees of a right angle to the axis of the bars and shall be fitted within 3 degrees of full bearing after assembly. Lap splice lengths can be reduced if the lap splice is properly conned by transverse reinforcement per TMS 402. ![]() ![]() In Section 12.15.1 in the notes under the splice requirements of 1.3(ld) for Class B splices it states, "where ld is calculated in accordance with 12.2 to develop fy without the modification factor of 12.2.5". End Bearing Compression Splices: Members with end bearing compression splices shall have vertical bars saw cut or otherwise finished for true bearing.
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