Ua ntej tshaj plaws, kev xaiv ntawm cov khoom xa tawm hauv cov chaw nres tsheb asphalt sib xyaw ua ke ib lub sijhawm tsim kev tsim kho, qhov siab dua, thiab kab rov tav loj dua. Nyob rau tib lub sijhawm, yuav tsum muaj qee tus nqi ntawm kev ua haujlwm thiab ntau lawm muaj peev xwm muaj peev xwm, thiab muaj peev xwm ntau lawm yog qhov dua 1.2 txog 1.5 zaug.

Qhov thib ob, ob lub ntsiab lus tseem ceeb ntawm cov asphalt sib tov chaw nres tsheb, txwv tsis pub nws yooj yim kom tau daig chaw nres nkoj ntawm cov chaw nres tsheb sib xyaw lossis raug thaiv vim arching. Lwm lub ntsiab lus yog tias thaum lub chaw nres tsheb asphalt sib tov yog nyob rau hauv tib lub vev xaib, nws tsis haum rau siv ntau cov khoom lag luam kom tsis txhob cuam tshuam nws txoj haujlwm ib txwm muaj.