Kua whakaaro koe he aha te take e rapu ana ngā DOT me ngā kaihanga papa motuhake i te "rap recycling hot mix asphalt plants services" i te 2 i te ata? He māmā noa te whakautu poto: kei te heke haere ngā tahua, kei te piki haere ngā utu katoa, ā, kua tāia ngā inenga oranga tonutanga ki roto i ngā pūrongo ā-tau katoa. Ko te whakautu roa ake—ā, he mea whakamere ake—kei roto i te huarahi e whakahaere ai ngā whare hou i te papa papa kua whakahokia mai (RAP) me te kore e huri i tō haerenga maeneene hei hakari poka.
Ehara te RAP i te "mea pango tawhito" ka hurihia i te huarahi. He ranunga tino whakahaeretia o te here uku tawhito me ngā konganuku kounga teitei kua whakamātauhia kētia ka taea e rātou te ora i ngā tau maha o te waka me te huringa huka-rewa. Ina kōrero ngā kaimahi kirimana mō ngā ratonga hangarua rap mō ngā tipu uku wera, ko te mea nui ko te mekameka o ngā tukanga - te mira, te wehewehe, te whakamātautau, te whakaranu, te whakamahana anō, me te whakatakoto - e hoatu ana ki ēnei rori kua whakarerea he oranga tuarua. He mea whakamere: ka taea e te maero kotahi o te huarahi tere o te tāone e whā ngā ara te whakaputa tata ki te 18,000 tana o te RAP. Tata ki te 1,200 taraka utaina rauemi e tono ana kia whai wāhi tuarua.
Me kōrero tātou mō ngā tau e menemene ai ngā kaiwhakahaere pūtea. Ko te piriti Virgin anake e 60% o te utu rauemi o te ranunga uku. Whakawhitihia ki te 40% RAP, ā, kua mukua e koe te 24% o taua raina i mua i te hokinga o te taraka tuatahi ki te kaiwhakapaipai. Mā te mahi i tēnā i runga i te whakahoutanga o te rohe 100,000-tana, ā, kei te kōrero tātou mō ngā penapena neke atu i te kotahi miriona tāra. Ae, e whitu ngā mati.
Engari ko te utu he haurua noa iho o te kōrero. Inaianei ka tohua e ngā tari ngā kaitono mō te tapuwae waro, ā, he maha ngā kawanatanga—e titiro ana ki a koe, ki Colorado me California—e tuku ana i ngā whakahekenga utu tono ina tutuki koe i ngā whāinga oranga tonutanga. I roto i te reo Pākehā māmā: hangarua ake, whiwhi mahi ake, me te whakanui ake i tō tawhē hua me te kore e whakakoi i tō pene ki runga i ngā tūemi tono katoa.
Kāore e ranea ngā poraka matapōkere. Ka kuruhia e ngā ratonga hou te RAP ki ngā whakaritenga rahi o runga—te nuinga o te ½ inihi (12.5 mm)—kātahi ka tātarihia kia rua ngā wāhanga. Ka hoki mai ngā overs mō tētahi atu haerenga; ka ripoata ngā mids ki ngā ipu whāngai makariri. Mā tēnei taahiraa anake ka whakanui ake i te wā mahi o te tipu mā te 15%, ā, ka ārai i ngā amuamu "paoa kikorangi" mai i ngā hoa noho tata.
Ka wera te RAP i te pito o te mura i ngā pahu tawhito e rere whakarara ana, ka waikura te hononga, ka pakarukaru te ranunga. Ka whakauruhia e ngā tipu rere-whakamuri o te whakatupuranga hou te RAP ki raro iho, kia matara atu i te mura tahanga. Te hua: ka noho pai tonu te hononga tawhito, ā, ka mau tonu te ātete pakaru pāmahana iti e hiahiatia ana e tō ranunga hangarua i roto i, hei tauira, i ngā marama o Pēpuere o Minnesota.
Anei te wāhanga whakamīharo: ka werohia e ngā miihini ngā ranunga whakaora hangarau—i ētahi wā he ranunga hinu koiora, i ētahi wā he ranunga hinu kakara—i te 0.3% ki te 0.6% te taumaha o te ranunga. Ka whakatauritea e ēnei matū te uku me te uku, ka whakahokia mai te ngāwari kia rite te ranunga hangarua ki te tunu hou 100%. Whakaarohia he rā kaukau mō ngā ngota uku ngenge.
Inaianei, kei ngā tipu e tika ana kia whakamahia, ka tāutahia ngā matawai tata-infrared (NIR) ki runga ake i te whitiki me ngā pūoko gamma i roto i te pū. Ka pānuihia e ēnei taputapu te ihirangi here, te makuku, me te pāmahana i ia 30 hēkona, ka whakarerekē aunoa i ngā kēti whāngai me te wahie mura. Ko te whakamaoritanga: he ranunga ōrite, he iti ake ngā kawenga kua whakakahoretia, ā, kāore he waea waea 3 i te ata mai i tētahi kaiwhakahaere kaupapa riri.
Engari i te kawe i te 62,000 tana o te RAP ki te whenua ururua, i hurihia e te mana whakahaere o te huarahi whakawhiti te 94% o taua mea ki roto i te paparanga teitei-whakawhiti. I oati te kaiwhakarato ratonga hangarua rap i te roanga o te ora o te ngenge mō ngā tipu arai wera, engari kua whakaatuhia kētia e ngā whakamātautau rutting wawe te mahi e rite ana ki te SMA tauhou—i te utu wae iti iho i te 28%. I penapenahia e ngā kaiutu taake te $3.4 miriona me te 3,900 tana metrika o te CO₂. Kāore i te kino mō te mahi o te rā.
He pai te whakahē. Ko te mea nui ko te hoahoa ranunga taurite: te tukatuka atamai i ngā wāhanga ōrite, te whakaranu tika i ngā mea e piri ai, me te whakahaere kounga pakari. Ina tohua aua pouaka, e whakaatu ana ngā raraunga ara o te National Center for Asphalt Technology (NCAT) e 50% o ngā ranunga RAP ka taea te rite ki te ātete ki te pakaru me te manawanui ki te ngatata o ngā ranunga hou. Whakamāoritanga: e kore tō rori e pakaru i mua i te huringa pōtitanga e whai ake nei.
Kāore e taea e ngā kākahu katoa he rua ngā ipu whāngai matao te whakahaere i te 50% RAP me te kore e huri i tō ranunga hei paoa paoa kikorangi. Rapua ēnei:
I waenganui i ngā utu hinu hurihuri, te korenga o ngā mea katoa, me ngā ture taiao e whakawhāiti haere ana, ko ngā kaimahi kirimana e kore e aro ki ngā ratonga tipu uku whakaranu wera, kei te tuku i te mahi e whai ake nei ki ngā kaiwhakataetae atamai. Nō reira, kua rite koe ki te whakarite i tō tono e whai ake nei? Waea atu ki tō kaihoahoa ranunga, pātai atu ki ngā hoa tipu pea me te rārangi arowhai i runga ake nei, ka mātakitaki i tō hua mō ia tana e piki haere ana i te hekenga o tō tatau waro. Ā, ā, i te wā e kī mai ai tētahi he "tuarua" te uku hangarua, me ataata noa, ka whakaatu ki a rātou ngā tatauranga o Pennsylvania Turnpike. He maha ngā wā ka mutu te kōrero a te tangata.