Umbala ovumayo ukufakwa phansi-ugcina ibhalansi yendawo ezungezile Umbala waphansi wokuvikelwa kwemvelo ovunyelekayo, owaziwa nangokuthi ukhonkolo omahhadlahhadla ombozwe ungqimba oluncane lukasimende, iqoqo kanye nokunamathisela usimende okuboshelwe komunye nomunye ukuze kwakheke ukusabalalisa okufanayo kwembotshana.
Ukugcinwa kwebhalansi yemvelo yombala wokuvikelwa kwemvelo okwazi ukungena phansi, okwaziwa nangokuthi "ukhonkolo onama-porous", ebusweni beqoqo elimahhadla elimbozwe ungqimba oluncane lukasimende olunamathiselwe, i-aggregate kanye nokunamathisela usimende okuboshelwe komunye nomunye ukuze kwakhiwe ukusabalalisa okufanayo kwezimbobo. esakhiweni sekhekheba lezinyosi, ngakho-ke inokungena komoya, ukungena kwamanzi kanye nezici ezingasindi, iphakamisa ngokuphumelelayo ukwenzeka kwamanzi futhi iqede ngokuphumelelayo izingozi zokungcoliswa kwemvelo ezifana nezinhlanganisela zamafutha emhlabathini. Iwumsebenzi omuhle kakhulu wokugandaya ukugcina ibhalansi yemvelo yemvelo. Iphansi elivumela ukungena ngombala lisebenza kuma-pavements, ezigcawini zomphakathi, ezindaweni zokupaka izimoto ezivulekile, emigwaqweni yasemapaki, emigwaqweni yabahamba ngezinyawo, emigwaqweni yokuhlala kanye neyasegcekeni lomphakathi njalo njalo.
