Me pēhea te tatau i te kaha o te raima i roto i te hanganga whare: He aratohu katoa
Ko te raima tētahi o ngā rauemi tino nui mō te hanganga whare. Mā te ranunga o te sima, te wai, te onepu, te kirikiri, te kirikiri rānei, ka homai e te raima he kaha me te manawanui tino pai ki tētahi hanganga. Ko te whakarite kia rawaka te kaha o te raima hei tu atu i ngā kawenga e pā ana he wāhanga nui o te whakamahere me te whakatinana i ngā kaupapa hanga. Ka matapakihia e tēnei tuhinga te huarahi ki te tatau i te kaha o te raima, ngā tikanga e whakamahia ana, me ngā āhuatanga e pā ana ki tōna kaha.
1. Te Mārama ki te Kaha o te Konukura
Ko te kaha o te raima ka inehia i roto i ngā megapascal (MPa) me ngā pauna ia inihi tapawha (psi) rānei, ā, e pā ana ki te kaha o te raima ki te tu atu i ngā kawenga mō ia wāhanga horahanga. Ko te raima e whakamahia ana i roto i te hanganga whare, ko te kaha pēhi, ko te kaha rānei o te raima ki te tu atu i ngā kawenga pēhi, hei tawhā matua.
2. Ngā Take e Pā Ana ki te Kaha o te Konukuraiti
He maha ngā āhuatanga e pāngia ai te kaha o te raima, tae atu ki:
– Te ōwehenga wai-sima (ōwehenga w/c): Koinei te ōwehenga o te nui o te wai ki te nui o te sima i roto i te ranunga raima. Ko te iti o te ōwehenga wai-sima ka hua ake he raima kaha ake.
– Te kounga o ngā rauemi mata: Ka pā te kounga o te sima, te wai, ngā mea whakahiato, me ētahi atu tāpiringa pēnei i te pungarehu rere, te paoa silica rānei ki te kaha o te raima.
– Te tukanga whakaranu: He mea nui anō hoki te ōritetanga o te ranunga me te roa o te whakaranu ki te whakatau i te kaha o te raima.
– Te tukanga whakapakeke: Ko ngā āhuatanga i te wā e whakapakeketia ana, pērā i te haumākū me te pāmahana, ka tino pā ki te kaha whakamutunga o te raima.
– Te pakeke o te raima: Ka piki haere te kaha o te raima i te roanga o te wā, ā, ka inehia i te 28 rā te pakeke.
3. Tikanga Whakamātautau Kaha o te Konukura
He maha ngā tikanga hei whakamātautau i te kaha o te raima, tae atu ki:
– Whakamātautau Kaha Pēhi: Koinei te tikanga e whakamahia whānuitia ana. Ka whakamatautauria he tauira raima porotaka (15 cm te whānui, 30 cm te teitei) he poraka rānei (15 cm x 15 cm x 15 cm te whānui) i roto i te mīhini pēhi kia pakaru rā anō. Ka tatauhia te kaha pēhi mā te wehewehe i te kawenga mōrahi i puta mai i te horahanga whakawhiti o te tauira raima.
– Whakamātautau Kaha Kume Wehewehe: Whakamahia hei aromatawai i te kaha kume ā-kore o te raima. Ka whakatakotoria whakapaetia he rango raima ki roto i te mīhini pēhi kōpeketanga, ā, ka tukuna he kawenga kia wehea rawatia te tauira rango kia rua.
– Whakamātautau Kaha Piko: Hei ine i te kaha piko, ka utaina he poraka raima o ngā rahi kua tohua kia pakaru rā anō. He maha ngā wā ka whakamahia tēnei tikanga mō te raima e tautoko ana i ngā kawenga piko, pērā i ngā kurupae me ngā papa.
4. Tātaitanga Kaha o te Konukura
Hei tatau i te kaha pēhi o te raima, ka whakamahia te tātai e whai ake nei:
\[ \text{Kaha Pēhi} = \frac{P_{\text{max}}}{A} \]
Kei hea:
– Ko te kawenga mōrahi rawa atu i inehia e te pēhi (i roto i ngā Newton, i ngā pauna rānei) \( P_{\text{max}} \)
– Ko te horahanga whakawhiti-wāhanga o te tauira raima (i roto i ngā mita pūrua, i roto rānei i ngā inihi pūrua).
Tauira tātaitanga:
Mena he 15 cm x 15 cm x 15 cm te rahi o tētahi poraka raima, ā, he 15 cm te rahi, ka pāngia e te kawenga mōrahi o te 450.000 N ina whakamatautauria mō te pēhanga, kāti:
\[ A = 15 \kuputuhi{ henimita} \times 15 \kuputuhi{ henimita} = 225 \kuputuhi{ henimita}^2 = 0,0225 \kuputuhi{ m}^2 \]
\[ \text{Kaha Pēhi} = \frac{450.000 \text{ N}}{0,0225 \text{ m}^2} = 20.000 \text{ kN/m}^2 = 20 \text{ MPa} \]
5. Ngā Paerewa me ngā Whakatakotoranga
Ko te kaha o te raima e hiahiatia ana mō tētahi kaupapa hanga ka whakatauhia i runga i ngā paerewa me ngā whakaritenga hangarau e tika ana. Ka rerekē pea ēnei paerewa puta noa i ngā whenua:
– SNI (Paerewa ā-Motu o Initonīhia): I Initonīhia, ka mahia te ine i te kaha o te raima i runga anō i te paerewa SNI 2847:2013 e pā ana ki ngā Tukanga mō te Tatau i ngā Hanganga Rakau mō ngā Hanganga Whare.
– ASTM (American Society for Testing and Materials): Ko te paerewa ASTM C39/C39M e whakahau ana i ngā tikanga hei whakatau i te kaha pēhanga.
– BS (Paerewa o Peretānia): I te UK me ētahi atu whenua, ko te BS 8110 te paerewa e whakamahia whānuitia ana.
6. Whakamātautau Papa
Ahakoa he tika pea ngā hua o ngā tikanga whakamātautau taiwhanga, he mea nui anō hoki kia whakahaerehia he whakamātautau parae hei whakatau i te āhua tuturu o te raima i te papa mahi. Ko ētahi o ngā tikanga whakamātautau parae ko:
– Whakamātautau Whakahoki Hama (Whakamātautau Hama Schmidt): He taputapu e whakamahia ana hei aromatawai i te pakeke o te mata o te raima, me te matapae i te kaha pēhi i runga i te nui o te whakahokinga.
– Whakamātautau Tere o te Pāorooro Ultrasonic: Ka ine i te tere o ngā ngaru ultrasonic i roto i te raima hei kite i te mātotoru me te pakari o te hanganga.
– Whakamātautau Wāhanga Windsor: Aromatawai i te kaha o te raima mā te ine i te hohonutanga o te werohanga o te pine whakarewa kua werohia ki roto i te mata raima.
7. Te Tiaki me te Aroturuki i te Konukuraiti
Kia ringihia te raima, kia whakamatautauria hoki, he mea nui kia whakarite i ngā āhuatanga pakari pai rawa atu kia tutuki ai te kaha e hiahiatia ana. Ko te pakari pai ko:
– Te Whakamaroke, te Whakapakeke rānei: Te whakatikatika i te taiao kia mau tonu te makuku o te raima. Ka taea tēnei mā te whakamahi i te kakahu haukū, te rehu wai, te wai whakaora rānei.
– Te Aroturukitanga i te Pāmahana: Me whakahaere te pāmahana o te raima i te wā e whakapakeketia ana, nā te mea ka pāngia e ngā piki me ngā heke o te pāmahana ngā hua kaha whakamutunga.
Whakamutunga
Ko te tatau i te kaha o te raima i roto i te hanganga whare he tukanga e uru ana ki te māramatanga hōhonu ki te hanganga o ngā rauemi mata, ngā tikanga whakamātautau tika, me te tiaki i muri i te whakarewanga. Mā te whai i ngā tikanga me ngā whakaritenga paerewa e tika ana, me te whakahaere i ngā whakamātautau pakari i roto i te taiwhanga me te mara, ka taea e tātou te whakarite kia tutuki i te raima e whakamahia ana i roto i tētahi kaupapa ngā whakaritenga kaha me te haumaru e tumanakohia ana.
Kia maumahara ko te angitu o tētahi kaupapa hanga e whakawhirinaki nui ana ki te kounga o te raima e whakamahia ana. Nō reira, he mea nui te tirotiro tupato me te tirotiro auau mō ia wāhanga o te mahi hanga. Mā tēnei ka puta he hua mutunga haumaru, pakari, me te kounga teitei.
