Land Subsidence, Earth Fissures, and Drought-Induced Foundation Collapse¶

Land subsidence, expansive clay shrink-swell heave, and earth fissures are ground-deformation hazards that crack building foundations, shear underground natural gas and water mains, jam residential exit doors shut, and open kilometer-long chasms across valley floors. Unlike sudden karst sinkholes that drop into limestone caverns, drought-induced subsidence and expansive soil movements attack buildings through two distinct geotechnical mechanisms. First, expansive smectite and montmorillonite clays (vertisols) act like a geological sponge, swelling with up to 500 to 1,000 kilopascals (10,000 to 20,000 pounds per square foot) of upward uplifting pressure during wet seasons and shrinking violently inward during severe droughts ka jusigilanw sama ka bɔ ɲɔgɔn na. Filanan, dugukoloji jibɔyɔrɔ tɛmɛnen min bɛ mɛn sen na, o bɛ kɛ sababu ye ka bɔgɔ ni bɔgɔdaga jugumanw (jidagaw) fara ɲɔgɔn kan kudayi ani ka jigin ni mɛtɛrɛ 1 fo 9 ye (mɛtɛrɛ 3 fo 30) kɔdingɛ bɛɛ kɔnɔ, ka kungo walima jikuruw sanfɛla sɔgɔ fo k’a da wuli dugukolo yɔrɔ belebelebaw fɛ minnu bonya bɛ se mɛtɛrɛ 10 ma (sen 33) ani A juguya ye mɛtɛrɛ 15+ ye.

Ameriki dugukoloko sɛgɛsɛgɛli (USGS), Angletɛri dugukoloko sɛgɛsɛgɛli (BGS), Bureau de Recherches Géologiques et Minières (BRGM Faransi, yɔrɔ min na bɔgɔdaga bɛ jate Catastrophe Naturelle belebeleba ye min bɛ wele ko Retrait-Gonflement des Argiles), ani Ameriki Injiniyɛriw ka tɔnba (ASCE), dugukolo bonyalenw ani dugukolo jukɔrɔla fɛnw tiɲɛni san o san ka tɛmɛ sanjiba, sanfiɲɛba ani fɔɲɔba kan u faralen ɲɔgɔn kan. Hali ni ɲɛgɛnw sigili dɔɔnin dɔɔnin ye sɔngɔ gɛlɛn dɔrɔn ye, diferential foundation failure rapide walima dugukolo fissure gully washout barikama kungo sanjiba waati la, o bɛ wuli ka kɛ ɲɛnamaya lakanani kɔrɔtɔko ye joona, ni a bɛ dugujukɔrɔ gazi pipe gɛlɛnw kari so jukɔrɔ, ka dugudenw minɛ da sɔgɔlenw kɔfɛ, walima ka bolifɛnw munumunu siraw tiɲɛnenw.

Aw bɛ o kɛ sisan¶

1. Aw bɛ kɛnɛma bɔda da ni sugolan finɛtiri bɛɛ kɔrɔbɔ so kɔnɔ joona, ani ka bɔyɔrɔ da o da wuli ni wedge walima prop ye min bɛ daminɛ ka nɔrɔ. Differential foundation sinking or clay heave twist rectangle door frames into parallelograms (structural racking). Ni dugukolo jiginna teliya la walima ni dugukolo tiɲɛna, ɲɛfɛda girinmanw, kɔfɛda ani garazi da bɛ se ka siri kosɛbɛ u ka fɛn tigɛlenw na fo i tɛ se k’u da wuli gazi tasuma walima sanfɛla bintɔ waati. Aw bɛ nɛgɛbere walima bɔgɔdaga dɔ mara aw ka sugo kɛrɛfɛ ani ka bɔyɔrɔ fɔlɔ kelen dɔrɔn to a ma datugu ani a ka baara kɛ.
2. Aw bɛ kɛnɛma lamini sɛgɛsɛgɛ, gazi jateminɛnan, propane sira ani jibolisiraba bɛ don aw ka jusigilan kogo walima bɛton sɔgɔlan na yɔrɔ min na. Aw bɛ taama kɛnɛma ka gazi wulilan pibiliki ni mɛtiri lajɛyɔrɔ lajɛ kosɛbɛ. Ni dugukolo y’a sama ka bɔ walima ni a jiginna mɛtɛrɛ jukɔrɔ walasa gazi pipe ka jɛngɛ ka jɛngɛ, ka a biri kɛrɛ fɛ, walima ka pinɛ biriki walima bɛton kogo jiginni kɔnɔ, aw bɛ gazi dawolo kunba datugu mɛtɛrɛ la ni santimɛtɛrɛ 30 (inch 12) ye min bɛ se ka ladilan (aw bɛ gazi kɛnɛman sɔgɔlan wuli degere 90 walasa a ka sigi ka kɛɲɛ ni a ye pipe) ani ka aw ka gazi baarakɛyɔrɔ wele joona.
3. Aw bɛ kɔnɔna ni kɛnɛma kogow karilenw suman ani k’u tigɛtigɛ ni "5-Millimeter / 15-Millimeter" sigicogo sariya ye. Kunsigi jalen karilenw jɔlenw milimɛtɛrɛ 1 fo 2 (1/16 inch) jukɔrɔ, a ka c’a la, olu ye ɲɛgɛnw sɔgɔli ye minnu tɛ kojugu kɛ. Nka, kɛrɛnkɛrɛnnenya la, jirisunba walima bɛton bloki kɔnɔ, faraw minnu ka bonya sanfɛ ka tɛmɛ duguma kan (walima a kɔfɛ, o b’a jira ko i bɛ wuli ka wuli), kɛrɛnkɛrɛnnenya la, ka fara duguma kogo kan, walima jusigilan kari fɛn o fɛn ka tɛmɛ milimɛtɛrɛ 5 fo 15 kan (insi ¼ fo ⅝) min bɛ bonya ka kɔlɔsi tile walima lɛrɛ caman kɔnɔ, o b’a jira ko jɔli jusigilan baarakɛlen dɛsɛra.
4. Aw bɛ to kɔfɛ mɛtɛrɛ 15 fo 30 (sen 50 fo 100) a dɔgɔyalenba la ka bɔ dugukolo da wulilen faralen bɛɛ la, dingɛ misɛnninw layini na, walima kungo kɔnɔ kɔji sinsinni na (Dugukolo-yɔrɔ). Bagan jalenw ni yɔrɔ jalenw na (i n’a fɔ Arizona, Kalifɔrni, Teksas, Nevada, Mɛkisiki dugu, Sinuwa woroduguyanfan, Iran, ani Ɛsipaɲi), dugukolo-yɔrɔ-yɔrɔ ka teli ka daminɛ dugukolo sanfɛ i n’a fɔ a kunsigi karilen min bɛ i n’a fɔ farati tɛ a la walima daisy-chain min bɛ kɛ ni dingɛ misɛnninw ye minnu bonya bɛ i n’a fɔ sosow (piping features). O dugukolo sanfɛla nɔgɔ finman in jukɔrɔ, tension jɔlen dogolen dɔ sigilen bɛ yen min juguya ye mɛtɛrɛ 3 fo 15 ye** k’a makɔnɔ a ka bin waati min na mɔgɔ, sow, bagan bagan walima mobili bɛ tɛmɛ a kan, walima waati min na samiyɛ sanfiɲɛba dɔ bɛ ji bɔn ka don farakurun kɔnɔ.
5. Aw kana bɔgɔdaga jalen jalen jigin siɲɛ kelen ni tasumamugu ye abada, ani aw kana a to abada bɔgɔmugu bɔgɔw ka tobi i n’a fɔ kolo. Ni aw ka so sigilen bɛ bɔgɔ belebeleba kan (vertisol / gumbo / cotton nɛrɛma / London bɔgɔ) funteni waati walima ja ani aw bɛ santimɛtɛrɛ 2 fo 8 (santimɛtɛrɛ 1 fo 3) yɔrɔ ye bɔgɔ jalen ni aw ka bɛton da la, aw bɛ ji kɛ dɔɔni dɔɔni, min bɛ kɔlɔsi ni soaker hose ye min bilalen don santimɛtɛrɛ 45 fo 60 (santimɛtɛrɛ 18 fo 24) ka bɔ jusigilan kogo la miniti 15 fo 30 siɲɛ fila tile kɔnɔ. Ni aw ye ji litiri ba caman fili ka ɲɛsin jusigilan da wulilen ma, o bɛ se ka kɛ sababu ye ka bɔgɔ wuli yɔrɔnin kelen walima ka bɔgɔ dɛmɛnanw ko.
6. Aw bɛ soba jibolisira datugu ni aw ye ji bolicogo mɛn bɛton sɔgɔlen jukɔrɔ walima ni aw ye yɔrɔ sumalenw ye/dugukolo tilew kɔrɔtalen (Under-Slab Plumbing Leak). Ni ja dɔgɔyali bɛ bɔgɔ sama ka jigin so dɔ jukɔrɔ min bɛ kɛ ni sɔgɔlan ye, nɛgɛjibɔlanw ni nɛgɛbɔlanw sirilen bɛ bɔgɔdaga jukɔrɔ tuma caman snap. O ji min bɛ bɔn o bɛ sɔrɔ ka bɔgɔ jalen jalen bɔgɔdaga dɔ fa ka tɛmɛ so cɛmancɛ jukɔrɔ yɛrɛ, ka kɛ sababu ye ka dome heave bɔ sanfɛ min bɛ kɔnɔna kogow kɔrɔta ni santimɛtɛrɛ 5 fo 15 ye (santimɛtɛrɛ 2 fo 6) dɔgɔkun kɔnɔ.

Foundation cracking, bɔgɔ wuli, ani dugukolo fissure triage flowchart¶

Aw bɛ baara kɛ ni nin ɛntɛrinɛti ni lakana latigɛ jiri ye walasa ka dugukolo karilenw, kogow karilenw, ani jusigilanw jiginni jateminɛ aw ka yɔrɔ lamini na.

flowchart TD
    Start["Dugukolo lamagacogo walima jusigilan karilen Kɔlɔsili:<br/>Kogow karilen, Da minnu bɛ nɔrɔ, dugukolo yɔrɔw, walima Dugukolo da wulilen"] --> DangerCheck{"Yala ƝƐNAMAYA-Lakanali<br/>DARAPO BILENNENW bɛ yen sisan wa?"}

    DangerCheck -->|"ƆWƆ: Gazi kasa / pipe min bɛ sɔgɔsɔgɔ, joists popping mankanba,<br/>so duguma kogo horizontal min bɛ wuli ka don kɔnɔna na (>santimɛtɛrɛ 2,5),<br/>walima barika la ka da wuli kɛnɛma i n’a fɔ canyon"| EvacImmediate["YƆRƆBƆLI ƝƐNABƆLI ƝƐNABƆLI ƝƐNABƆLI :<br/>1. Aw bɛ mɔgɔw & sokɔnɔbaganw bɛɛ bɔ yen mɛtɛrɛ 30+ (100+ ft) yɔrɔ la<br/>2. Aw kana maga yeelenbɔlanw, minɛnw, walima garazi da la<br/>3. Aw bɛ kɛnɛma gazi jateminɛnan & jibɔyɔrɔ datugu DƆRƆN ni a lakananen don ka se<br/>4. Aw bɛ telefɔni 911 / 112 / 999 wele ani Gazi baarakɛlaw ka kɔrɔtɔko sira"]

    DangerCheck -->|"NO teliya la binkanni walima gazi bɔli:<br/>Aw bɛ dugukolo walima jɔli lamagacogo suguya jateminɛ"| PatternType{"I bɛ kari walima<br/>dugukolo tiɲɛni cogoya jumɛn ye ?"}

    PatternType -->|"1. Kari janya sinsinni / Dingɛw layini ka tɛmɛn Yard, Baganmarayɔrɔ,<br/>walima sira kan Basin jalen / Dugukolo jukɔrɔji-pompilen kɔnɔ"| EarthFissure["DUGUKO ƝƐNABƆLI (Subsurface Tension Void):<br/>1. Kogo/kase ka bɔ mɛtɛrɛ 15 fo 30 (sen 50 fo 100) buffer zone la<br/>2. AW KAN’a taama abada, ka sow boli, walima ka bolifɛn ta abada kunsigi dugukolo faraw kan<br/>3. Divert roof downspouts & storm runoff AWAY from the crack<br/> (sanji bɛ santimɛtɛrɛ 2 farakurun tigɛli kɛ ka kɛ mɛtɛrɛ 5 bɔgɔdaga ye miniti damadɔ kɔnɔ)<br/>4. Rapport min bɛ kɛ jamana ka dugukoloko sɛgɛsɛgɛlikɛla ye / County Flood Control"]

    PatternType -->|"2. Waati kɔnɔna na, birikiw karilenw,<br/>Dabaw bɛ nɔrɔ, & santimɛtɛrɛ 2 fo 8 cɛmancɛ bɛ kɛ Slab Edge lamini na ja la"| ClayShrink["BƆGƆ ƝƐNABƆLI / SIGIDA ƝƐNABƆLI:<br/>1. Aw bɛ gazi & jibolisiraw lajɛ minnu bɛ don jusigilan na ni u tɛ sɛgɛn<br/>2. Aw bɛ jisumabɔlan bila santimɛtɛrɛ 45 fo 60 (santimɛtɛrɛ 18 fo 24) ka bɔ a jusigilan na<br/> (ji bɛ kɛ dɔɔni dɔɔni miniti 15 fo miniti 30/tile walasa dugukolo nɔgɔ ka to cogo kelen na)<br/>3. Aw kana jiri minnɔgɔlenw turu minnu ka surun ni u janya kɔgɔlen ye 1,0x ni 1,5x<br/>4. Aw bɛ taa Structural / Geotechnical Engineer (PE) dɔ la min ka lakɔliso sɛbɛn bɛ a bolo ."]

    PatternType -->|"3. Bɛton sɔgɔlen cɛmancɛ min bɛ kɔrɔta san fɛ (Doming),<br/>Dugukolo sumayɔrɔ, walima Ji min bɛ wuli ka wuli"| SlabLeakHeave["UNDER-SLAB PLOMBING LEAK MIN BƐ BƆGƆ KƆLƆSI:<br/>1. Aw bɛ ji jateminɛnan bɔgɔbɔli jiralan lajɛ ni pɔnpe bɛɛ fagalen don<br/>2. Aw bɛ soba jidagayɔrɔ datugu walasa ka bɔgɔ funu sigida la<br/>3. Aw bɛ plombier wele walasa ka hydrostatique/acoustique slab bɔgɔbɔli dɔn<br/>4. Aw kana kogo jalenw siri fo bɔgɔ nɔgɔ ka sabati"]

Dugukolo lamagacogo ni jusigilan faratiba 5 sumalen¶

Dutigiw, bolifɛntigiw ani kɔrɔtɔko ɲɛnabɔbagaw ka teli ka bɔgɔ lamagacogo belebeleba, marabolo jibɔyɔrɔw jigincogo, dugukolo faralenw, karst jibɔyɔrɔw, ani jikuruw sɔgɔli ɲagami ɲɔgɔn na. Ni i y’a dɔn dugukoloko taabolo min bɛ i sen kɔrɔ, o de bɛ a jira i bɛ se ka to i yɛrɛ la cogo min na.

Deep dive 1: Bɔgɔbɔgɔ min ka bon ("The Hidden Disaster") bɛ sow tiɲɛ cogo min na ja ni sanji fɛ¶

Bɔgɔdaga belebelebaw, minnu bɛ wele marabolow la ko bentonite walima Pierre Shale Koloradugu ani Dakota, Houston Black Clay / Gumbo Texas, Yazoo Clay Misisipi, London Clay Angletɛri Saheli fan bɛɛ fɛ, Argiles Vertes Faransi, ani Black Cotton Soil (Vertisols) Ɛndujamana fan bɛɛ fɛ, Ɔsitarali, ani Afiriki, smectite-group bɔgɔdaga (kɛrɛnkɛrɛnnenya la montmorillonite) bɛ sɔrɔ. A tɛ i n’a fɔ cɛncɛn walima bɔgɔmugu kisɛ minnu bɛ sigi ɲɔgɔn kɛrɛfɛ dɔrɔn, mɔntmorillonite kristalɛw ye joli-sira-funu fla-fla mikoroskɔpikiw ye minnu kuran charge négatif barikama bɛ u sanfɛ. 1. Mun na bɔgɔ belebeleba bɛ sow kɔrɔta minnu bɛ sanfɛyɔrɔ caman na (Funfunu waati): Ni sanjiji walima ji min bɛ bɔ pɔmpi kɔnɔ, o magara montmorillonite bɔgɔ jalen na, polar ji molekilɛriw (\(H_2O\)) ani ion charge positif (\(Na^+\), \(Ca^{2+}\), \(Mg^{2+}\)) bɛ sama ni fanga ye bɔgɔdaga mikroskɔpikiw cɛ, ka kristalɛ latice wajibiya a ka bonya i n’a fɔ accordéon. Bɔgɔ belebeleba min datugulen don, o bɛ sanfɛ funu degunw lase \(250\text{ ma ka se }1,000+\text{ kilopascals}\) ma (\(5,000\text{ ka se }20.000+\text{ kilo ma sen kɛrɛnkɛrɛnnen kelen na}\)). Ikomi sigiyɔrɔ min bɛ kɛ sankanso kelen walima sankanso fila ye, o bɛ \(50\text{ fo }150\text{ kilopascals}\) (\(1,000\text{ ka se }3,000\text{ psf}\)) dɔrɔn de kɛ duguma a senw kan minnu man dun, bɔgɔ funun bɛ bɔgɔdaga dɔ dawolo walima a cɛmancɛ kɔrɔta nɔgɔya la sanfɛ i n’a fɔ a jaki jilama. 2. Mun na ja dɔgɔyali bɛ sɔgɔsɔgɔninjɛw tigɛ tilancɛ la ("Edge Drop / Center Doming"): Samiya jan kɔnɔ ja or tariku funteni dome, bɔgɔ min bɛ so kɛnɛma lamini lamini, o bɛ ja ka dɔgɔya ka wuli ka jɔ ani ka jigin ni kɛmɛsarada la 10 fo 25 ye, k’a sɔrɔ bɔgɔ min ka dun bɛton cɛmancɛ jukɔrɔ, o bɛ to ka ɲigi ani ka funu bawo bɔgɔdaga b’a tanga bɔgɔbɔgɔli ma. - Ni lamini bɔgɔ bɛ dɔgɔya ka taa, so jusigilan kɛnɛma dakunw bɛ to ka jɛngɛ u ma dɛmɛn fiɲɛ na (kantilever) cɛmancɛ dɔ kan min bɛ \(2\text{ ka se }8\text{ santimɛtɛrɛ}\) ma (\(1\text{ ka se }3\text{ inches}\) ma). - Janya bɛ lamini kogow sama minnu ma dɛmɛ ka jigin (edge drop / center doming), ka bɛton sɔgɔlen kɔrɔta cɛmancɛ kulu ɲiginnen kan fo ka se jirisunba ma ka tigɛ tilayɔrɔ fila la, ka kɔnɔna jalen tigɛ ni degere 45 ye da laminiw sanfɛ ani ka kɛnɛma biriki siminiw sama ka bɔ so sanfɛla la.

Jiri ju jalen cayalan ("Jiri janya 1x ka se 1,5x ma" sariya) .¶

Angletɛri jamana ka dugukoloko tɔnba (IStructE), Angletɛri dugukoloko sɛgɛsɛgɛlikɛla, ani Faransi BRGM ka fɔ la, ja jusigilanw tiɲɛni jugu kɛmɛsarada la 50 ni kɔ bɔgɔbɔgɔw kan, o bɛ sɔrɔ jiri belebelebaw fɛ minnu falen don so gɛrɛfɛ kojugu: - Oak, willow, poplar, eucalyptus, elm, ash, walima cottonwood jiri kɔgɔlen kelen bɛ ji litiri 400 fo 1000+ (galɔn 100 fo 260+) bɔ tile kɔnɔ ka bɔ bɔgɔ la i ka jusigilan jukɔrɔ samiyɛ ja waati la, ka bɔgɔ kolo sama ka jigin fo ka se 3 fo 5 ma mɛtɛrɛ (sen 10 fo 16). - Sɛnɛyɔrɔ janya lakananen: Aw kana jiriw turu abada minnu buluw ka jan, minnu ka surun jusigilan na bɔgɔbɔgɔ la ka tɛmɛ 1,0 fo 1,5 kan ka tɛmɛ jiri kɔgɔlen janya kan (\(15\text{ ka se }25\text{ mɛtɛrɛ}\) [\(50\text{ ka se }80\text{ feet}\)] ma). - Lakɔlɔsili Jiri tigɛcogo barikama kan: Ni jiri belebeleba dɔ, min si bɛ san tan caman bɔ, kaban ka falen i ka so kɛrɛfɛ yɛrɛ bɔgɔ belebeleba kan, AW KAN’a jiri tigɛ siɲɛ kelen na k’a sɔrɔ aw ma taa dugukoloko injiniyɛri dɔ ɲininka. Ni jiri kɔgɔlen dɔ tigɛra yɔrɔnin kelen, bɔgɔbɔrɔ jalen min bɛ so jukɔrɔ, jiri ye min ja san 30 kɔnɔ, o bɛna ji minɛ kokura san 2 fo san 5 nataw kɔnɔ, ka funu ka taa sanfɛ (post-removal clay heave), ka so kɔrɔta ani k’a kari ka juguya ka tɛmɛ ja kan yɛrɛ. Koronawirisi dɔgɔyali tigɛcogo kɔrɔsilen ni jirisunw barikalanw ye fɛɛrɛ wɛrɛw ye minnu farati ka bon.

Structural Crack Triage Table: Sow ka faratiw hakɛ kalanni (BRE Digest 251 / ASCE sariyaw) .¶

Diɲɛ kɔnɔ, jɔli injiniyɛriw bɛ baara kɛ ni BRE Digest 251 (Building Research Establishment) faraw bonya danfara sɛgɛsɛgɛli ye walasa ka ɲɛgɛnw dilanni plastiki faraw faranfasi minnu tɛ kojugu kɛ, ka bɔ jɔli jusigilan tiɲɛni faratilen na:

Deep dive 2: Dugukolo-yɔrɔba ni dugujukɔrɔjiw jigincogo¶

Dugukolo jukɔrɔjiw la diɲɛ fan bɛɛ la, i n’a fɔ Arizona (Phoenix, Pinal County, Tucson, Cochise County), California ka San Joaquin ani Coachella gunw, Texas (Houston-Galveston ani El Paso), Nevada (Las Vegas gun), Utah saheliyanfan (Cedar Valley / Enoch), Mɛkisiki dugu ani Mɛkisiki cɛmancɛ kɔw, Sinuwa woroduguyanfan kɛnɛba (Beijing-Tianjin), Iran ka Tehran ani Rafsanjan kɛnɛbaw, ani Espagne ka Guadalentín Basin, dugujukɔrɔjiw pɔnpe jugumanba san caman ja waatiw la, o bɛ kɛ sababu ye ka dugukolo sanfɛla jigin joona.

Kunsigi tigɛyɔrɔ fitinin dɔ bɛ wuli cogo min na ka kɛ bɔgɔdaga ye min juguya ye mɛtɛrɛ 15 ye wulada kelen kɔnɔ¶

1. Differential Compaction Over Buried Bedrock Highs: Ni ji bɛ pɔnpe ka bɔ kungo kɔnɔ jisigiyɔrɔ juguman dɔ la, nɔgɔmugu gɛlɛn minnu ma sabati kɔdingɛ cɛmancɛ la, olu bɛ ɲɔgɔn sɔrɔ ka jigin ni \(1\text{ ka se }5\text{ mɛtɛrɛ}\) (\(3\text{ ka se }16\text{ feet}\) ma), k’a sɔrɔ nɔgɔ finmanw bɛ kulu da la walima buried dɔ kan dugujukɔrɔ farakurunba bɛ jigin dɔɔnin dɔɔnin.
2. Subsurface Tensile Rupture: Nin diferential sinking in bɛ kungo dugukolo sanfɛyɔrɔw kɔrɔta ka tɛmɛn farakurun suturalenw kan, ka dugukolo sama ka bɔ ɲɔgɔn na ka kɛɲɛ ni ɲɔgɔn ye (tensile strain). Dugukolo jukɔrɔla juguman na (\(5\text{ ka se }20\text{ mɛtɛrɛ}\) ma duguma), tension vertical crack bɛ da wuli, hali k’a sɔrɔ sanfɛla \(1\text{ ka se }2\text{ meters}\) sanfɛla bɛ bɔgɔdaga tigɛ a cogo la.
3. Sussurface Piping and Roof Collapse: Ni sanji misɛnninw bɛ jigin ka bɔ sanfɛ ka don o dugujukɔrɔ fara dogolen na, a bɛ nɔgɔ lafiyalenw ko ka taa duguma, ka dugujukɔrɔla kɔba dɔ kɔnɔna na, min bɛ kungo duguma, santimɛtɛrɛ damadɔ dɔrɔn. Ni i y’a lajɛ, i bɛ min ye, o ye kunsigi tigɛlen fitini ye walima \(20\text{-centimeter}\) dingɛ misɛnninw tigɛlen.
4. The Flash-Flood Washout: Ni samiyɛ sanjiba walima sanjiba dɔ nana (aw ye an ka... flash sanjiba ɲɛminɛbaga), dugukolo kan ji sɛbɛnw bɛ bɔn o dingɛ misɛnninw kɔnɔ. Miniti 15 fo 60 kɔnɔ, ji min bɛ girin, o bɛ nɔgɔ sanfɛla finman bin dugujukɔrɔ tension crack janya bɛɛ la, ka kɔji dɔ da wuli min kogo jɛlen don, a bonya bɛ se mɛtɛrɛ 2 fo 10 ma, a juguman bɛ se mɛtɛrɛ 5 fo 15 ma (mɛtɛrɛ 16 fo 50), ani ka se kilomɛtɛrɛ 3 fo 15 ma. janya**, ka sirabaw tigɛ tilayɔrɔ fila la, ka sanjiba kunbɛnni bajiw tigɛ, ka sow tiɲɛ.

4 Lakanali sariyaw wajibiyalenw ka ɲɛsin ɲɛnamaya ma walima taama ma dugukolo farali yɔrɔw la¶

1. Never use an earth fissure or ground crack to dump yard waste, trash, fill dirt, or storm runoff. Homeowners frequently try to "fill in" a ground crack on their property by bulldozing loose dirt or routing roof gutters into it. Loose fill dirt washes straight down into the deep underground tension void, and routing water into a fissure accelerates underground erosion toward your house foundation.
2. Keep livestock, horses, ATVs, and hikers away from linear alignments of desert bush growth or small holes. In arid pastures, earth fissures often trap tiny amounts of moisture before they collapse, creating a suspiciously straight line of green creosote bushes or mesquite trees across dry dirt, dotted with small collapsing holes. A horse or ATV crossing that line can break through the thin soil bridge into a 10-meter vertical slot.
3. Check official Earth Fissure Maps before buying property or building: In the United States, the Arizona Geological Survey (AZGS) Natural Hazards Viewer, the United States Geological Survey (USGS) Land Subsidence Portal, and the Houston-Galveston Area Subsidence District publish street-level GIS maps of active earth fissures and subsidence zones.
4. Aw kana dugujukɔrɔji nɔgɔ abada ni bɔgɔdaga ye: Ikomi dugukolo sɔgɔli ye sira jɔlen ye min bɛ jigin mɛtɛrɛ tan walima kɛmɛ caman na ka taa jidagayɔrɔ la, k’a sɔrɔ dugukolo ma sama, jibolisiraw bɔli, fɛnɲɛnamafagalanw bɔli, walima bagan salenw minnu binna farakurun kɔnɔ, olu bɛ marabolo ka ji minta yɔrɔ nɔgɔ k’a ɲɛsin a yɛrɛ ma.

Safe emergency foundation moisture management during a drought¶

If you live on expansive clay soil during an extreme ja, your goal is not to make the soil muddy, which triggers upward swelling heave, nor to let it bake dry, which triggers downward shrinkage drop. Your goal is uniform, constant moisture around the entire 360-degree perimeter of the house:

• Use a slow soaker hose or drip irrigation line placed 45 to 60 centimeters (18 to 24 inches) away from the foundation wall: Never lay a soaker hose directly against the concrete slab edge where a dry gap has already opened; water pouring straight down that gap will pool underneath the footing and soften the bearing capacity of the soil. Placing the hose 45 to 60 centimeters out allows moisture to wick sideways and evenly through the root zone.
• Water the hot south-facing and west-facing walls 25 to 50 percent longer than shaded north-facing walls: Differential foundation cracking almost always starts at the southwest corner of a house (in the Northern Hemisphere) because afternoon solar heat bakes the south and west soil dry while the north wall stays damp in the shade.
• Maintain positive grading and extend roof gutter downspouts at least 1.5 to 3 meters (5 to 10 feet) away from the foundation: When drought finally ends with a torrential downpour, roof water dumping straight at the corner of the house will super-swell that single corner while the rest of the foundation remains dry, snapping the slab on the rebound.
• Check for hidden plumbing leaks monthly using your water meter's low-flow leak indicator: Turn off every faucet, ice maker, and toilet inside the house, then look at your street water meter for 10 minutes. If the small red or blue triangle/star dial is spinning at all, you have a hidden supply pipe leak that can cause catastrophic clay heave under your slab.

Ɲininkali minnu bɛ kɛ tuma caman na¶

How can I tell if a crack in my house wall is harmless cosmetic settling or a dangerous structural foundation failure?¶

Check the crack's width, direction, and whether it changes over time. Hairline vertical cracks narrower than 1 to 2 millimeters (1/16 inch) along drywall tape joints or above door corners are almost always harmless cosmetic shrinkage. Conversely, diagonal stair-step cracks cutting through exterior brick or concrete block, horizontal cracks accompanied by inward bowing on a basement wall, cracks that are much wider at one end than the other (indicating rotational tilting), or any crack wider than 5 millimeters (3/16 inch, roughly the width of a pencil) accompanied by doors and windows that suddenly jam shut indicates active structural foundation movement that requires inspection by a licensed structural engineer.

Why is it dangerous to flood the gap next to my house foundation with a garden hose during a drought?¶

When severe drought shrinks expansive clay soil away from your concrete foundation slab, leaving a 2 to 8 centimeter (1 to 3 inch) gap around the perimeter, pouring massive amounts of water directly into that open crack causes two engineering failures. First, free water runs straight down the crack beneath the concrete footing, turning the load-bearing soil layer into weak mud so the wall sinks even deeper. Second, sudden localized saturation causes that one wet spot of montmorillonite clay to swell violently upward while adjacent dry sections remain dropped, creating severe differential shear stress that cracks the slab. Instead, place a slow soaker hose 45 to 60 centimeters (18 to 24 inches) away from the foundation wall and run it for short 15-to-30-minute intervals to rehydrate the soil gradually.

What is the difference between an earth fissure and an earthquake fault or karst sinkhole?¶

Unlike an earthquake fault (which is driven by deep tectonic plate movement and releases seismic shockwaves) or a karst sinkhole (which forms when acidic water dissolves limestone cavern roofs), an earth fissure is a tension crack caused by human groundwater pumping in arid basins. As excessive pumping drains the aquifer, the valley floor compacts and sinks by several meters; where that sinking sediment stretches over a buried bedrock ridge, the ground pulls apart horizontally underground. When heavy rainwater pours into the hidden tension crack, it erodes the soil roof from below and collapses suddenly into a steep gully up to 10 meters wide and kilometers long.

Why can cutting down a large mature tree next to my house actually crack my foundation worse than leaving it there?¶

If a thirsty tree (such as an oak, willow, poplar, or eucalyptus) has grown next to a house on expansive clay soil for 20 to 40 years, its roots have permanently sucked a deep pocket of clay bone-dry beneath that side of the building. If you suddenly chop the tree down completely, the dead root zone stops removing water; over the next 1 to 5 rainy seasons, that desiccated clay pocket absorbs thousands of liters of water and swells upward by 5 to 15 centimeters (2 to 6 inches), lifting that side of the house in a destructive process called post-removal clay heave. Always consult a geotechnical engineer or arborist before removing mature trees on clay soil.

Sosow sɛgɛsɛgɛra¶

• United States Geological Survey (USGS): Land Subsidence in the United States (Circular 1182 & 1405), Aquifer System Compaction, and Earth Fissure Mechanics in Alluvial Basins.
• Arizona Geological Survey (AZGS): Earth Fissure Center, Subsurface Piping Collapse Dynamics, and Homeowner/Livestock Safety Guidelines Around Active Fissures.
• British Geological Survey (BGS) and Building Research Establishment (BRE, United Kingdom): Shrink-Swell Clay GeoSure Hazard Mapping, BRE Digest 251 (Assessment of Damage in Low-Rise Buildings), and NHBC Chapter 4.2 (Building Near Trees on Expansive Clays).
• Bureau de Recherches Géologiques et Minières (BRGM, France): Retrait-Gonflement des Argiles (RGA) Prevention and Structural Mitigation Standards.
• Federal Emergency Management Agency (FEMA, Etazuni) ani Ameriki ka Siwili Ɛnjiniyɛriw ka tɔn (ASCE): Dugukolobaw ni sigiyɔrɔw jusigilanw dilanni sariyaw (ASCE 7 / PTI DC10.5 Slab-on-Ground Design on Expansive Clays).

Gafe minnu bɛ tali kɛ o ko la¶

• Sinkɔlɔw : lasɔmini taamasiɲɛw ani mɔgɔw bɔli teliya la
• Ja: ji lakanani ani du kɔnɔ ɲɛnamaya
• Dugukolo yɛrɛyɛrɛ: jigin, datugu, minɛ, ani yɛrɛyɛrɛ kɔfɛ
• Sanjiba minnu bɛ kɛ joona: dugukolo sanfɛyɔrɔw bɔli teliya la
• Historic heat domes and extreme temperature survival