A Giant Sword, A Shield That Blows Up, and Reactive Armor

[Sciencezam]

In the universe of Muv-Luv Alternative, giant robots (called TSFs) sometimes use shields. These shields have reactive armor plates on them, which are frequently used to punch aliens in the face with explosions. How would one model such a shield, and that attack? I've not been able to find a plain reactive armor system-just EMA from ultratech and Laminates from High-tech, one of which is too high-tech for the setting and the other of which is not quite what's being used. I'm tempted to just have it provide a bonus to crushing damage when shield bashing, but I'm not real sure what a good benchmark for that bonus damage would be.

Along similar lines I've had some trouble modeling the swords used by the giant robots, as they're SM +6 with dST 30, and the low-tech companion 2 table only covers ST up to 100. Is there some further extrapolation of it I could use? The mecha are being done up under Spaceships rules.

Further explanations of the exploding shields are here. The world of the games is TL 8 with bits of TL9 appearing as cutting-edge equipment and the tech required to get mecha running.