In precast concrete construction ties may be provided wholly within in-situ concrete toppings or connections partly within in-situ concrete and partly within precast members or wholly within precast members but they should be effectively continuous. In addition the tie should also satisfy one of the following conditions:
- A bar or tendon in a precast member lapped with a bar in in-situ connecting concrete bounded on two opposite sides by rough faces of the same precast member.
- A bar or tendon in a precast concrete member lapped with a bar in in-situ topping or connecting concrete anchored to the precast member by enclosing links. The ultimate tensile resistance of the links should be not less than the ultimate tension in the tie.