TAKOBOTO

of course, expected result
Of course it's cold. ; As you would expect...
〜（の）は当り前だ　 〜（の）は当然の結果だ

Add formation 

また、テロがあったそうだ。くうこうのてにもつけんさがげんじゅうなわけだ。

Looks like there was another case of terrorism. As you'd expect, the inspection of carry-on luggage at the airport is really strict.

「このへやさむいですね。」「さむいわけです。まどがひらいています。」

"This room's pretty cold, huh." "Of course it's cold. The window is open"

なみがたかいわけだ。たいふうがちかづいているんだった。

Of course the waves are high. I mean, there is a typhoon coming.

こどもが４にんもいるから、わたしはまいにちがんばってはたらいているわけです。

I've got four kids, so as you'd expect, I work really hard every day.

このみちのあたりはじゅうたいであって、まわりみちわけだ

Around of this road A congestion, detour of course

The speaker's conclusion obtained through deductive, logical judgement or calculation on the basis of what he has heard or read.

Formation

(i) {V / Adj} (i) inf わけ　だ
　　｛話す・話した｝わけ　だ　(I take it that s.o. talks / talked)
　　｛食べる・食べた｝　わけ　だ (I take it that s.o. eats / ate)
　　｛高い・高かった｝わけ　だ (I take it that s.o. is expensive / was expensive)

(ii) Adj (na) stem ｛な・だった｝わけ　だ
　　｛静かな・静かだった｝わけ　だ　(I take it that s.o. is / was quiet)

(iii) N　｛という・だった｝わけ　だ
｛先生という・先生だった｝わけ だ (I take it that s.o. is / was a teacher)

lenzras