DIEN OAN KHOA HOC CONG NGHE
VE NGUYEN NHAN GAY HI/ HAI VA BIEN PHAP Xl/ LY BAO VE DA THIEN NHIEN 6 P LAT TRANG T R I CONG TRINH KIEN TRUC
Hidn nay v i trong tuwig lai chOng ta da v i se
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phit trien sU dung nhiiu d i thien nhidn d l dp, lit trang trf va xiy dung edng trinh, vi ngudn tai nguydn d i thidn nhidn ciJa ta phong phii v i khdi lupng v i chung loai, cd bin chit bin vQng v i ciu trOc, khi ning ehju luc v i ed miu sic. Song khdng t h i cd vat lieu bin vQng tuyet ddi vTnh ei>u vdi tic ddng dli thay cua khf hau thidn nhien, mdi trudng theo thdi gian tin tai ciJa nd.That viy, vit li#u da thidn nhien dat trong khdng khi ti;do dudi tic dung cua khi hiu thdi tiit, sau mdt thdi gian dii cung ehju nhUng biin doi ding k l , dd i i nhQng tic ddng vit ly, hda hpe, sinh vit hpc, v i co hpc...
1. Nhi7ng t i e dong vat ly: Ydu td vit ly lim giam chit iuong cua eic nham thach l i su biin ddng Idn cua nhiet dO ddng thdi vdi su cd mat eiJa nudc.
Vdfi tac dpng niy, ndu nhu loai d i khdng du bdn chie, khdng cd sUc lien kit Idn thi chiJng phii ehju nhiing ndi Ung suit Idn do din ndvi nhiet, hoac hien tupng nd truong do nudc ddng bang va tu tang t h i tfch, gay ndn su nUt vd bd mit, bde tich manh lim hu hai din vit lieu d i dung trdn cdng trinh.
2. Nhi?ng tac dpng hda hpc: Cic yiu t i xim thuc hda hpc trong thien nhien nhu khi caebonie va khf sulfua trong khi quyin. Nd cd tic dung nhu nhQng axit xim thuc manh ddl vdi cic khoang vat tfnh kiim trong nham thach v i nhit l i ddi vdi d i vdi.
Khi khf cacbinic trong sued mat cua nudc se chuyen cacbonat canxi khdng hda tan thinh bicaebonat canxi hda tan, chit niy bi nudc lam trdi cudn di khi mua gid. Khi sulfua khi ed mit cua nudc se chuyen thinh axit suifuaric, chit niy cung giy tic dung trdn d i vdi va tgo thinh sulfit axit canci dd hda tan. TU hat hidn tupng dd giy ndn hidn tupng da bj xim thuc, b i mat d i bj sCii, nham, mun din.
3. NhiJng y i u t6 khac giy phi hoai d i t i cic vi sinh vat, thuc vat: trong biu khdng khf cua cae thinh phi Idn v i nhOng trung tim cdng nghidp cd chUa nhijng bgi bin khie nhau (bui dit cit, bui than, bui khdi...) ndcd t h i bjUdpng lai dnhOngbd phin edng trinh phing ngang hoac hdi nghieng, cic Ic^ bui niy giU Im, gid cd thi dem din nhUng mam sinh vit, thyt vit, chOng tu dpng v i sinh sdi phit trien d dd nhd dd I m v i giy ndn d diy vit chit tfnh axit do qui trinh t^o thinh axit humic, cd tic dung xim thuc tfnh axit ddi vdi vit lieu d i .
DO I m trong ndn dit cung giy tic hai ddi vdi da xay dyng, nhit l i ddi vdi nhQng loai d i cd Id rdng hd v i nudc ed t h i xim nhip vio d i bing cac mao quin. Trudng hop bj bing Ignh thi da bj phi hoai do
G S . TS. NGUYEN MANH KIEM su tn/ong nd t h i tfch cua nude ddng bing. Hien tupng niy it gap d khf hau nudc ta, nhung cd the gap phii d mdt sd cdng trinh die biet vci trang bj ky thuit ddng lanh, didu hda, didu tiit khf hiu. Trudng hpp thudng gap la trong nudc cd chUa eic loai mudi hda tan, khi dd xiy ra hien tupng phi hoai d i do qui trinh dang thim eua nudc vio d i qua mao quin tU dudi ngim len, tren b i mat da tiep xue vdi khf quyen ndng, giy hidn tupng bic hoi v i tao thinh mdt ehu trinh kfn hut thim nudc tU ndn dit Idn mat thoang ngoii khdng khf, qui trinh bay hdi chi cd nude bde dij cic mudi cdn Igi se kdt tinh, mudi kit tinh se din din trdn b i mat d i nhOng bui tring hoen bin lim xiu b i mat da. Cd the gay ra hien tudng phi hijy mat d i do Ung luc truong nd khi cac mudi kit tinh gin b i mat lim giim din din chit lUdng d i .
4. Hien tUdng biin mau eua mdt sd logi d i sau mOt qui trinh khai thic hoic sQ dung vio cdng trinh.
Hidn tupng nay sinh ra do nhQng qui trinh d xy hda bdi d xy ed trong khdng khi. Nd tic dung ldn mdt sd khoing vit trong d i nhu cic sulfua hoic tren nhUng mim hQu co an trong da. Tic dung d xy hda se cing mgnh dudi eic tia ning mat trdi, nhit i i cic tia tim.
Hien tupng niy xuit hien nliliu d c i c d i hoa trang tri (cd mau sic) bdn ngoii cdng trinh.
D l bao ve d i xiy dung tU cic tic dyng xim thyc ndi tren ngudi ta dQng nhQng bien phip ca v i mat ciu tao kidn true c i vd mat sCr ly bd mat d i sau khi d i dat vio cdng trinh.
- Biin phip ciu t^o kiin tnic: Cin hgn chi hogc trinh dp d i d cac b i mat ngoii phing ngang hoac it nghieng, de khdng tgo khi nang gay U dpng nudc xim thyc hoic cic bui bin d trong khdng khi trdn mat da. Ndu nhu da dung d phin ndn v i da khdng thit chic die 6e 6ii ngin trd vide thim nudc theo mao quan thi phai lam Idp ngin ching nudc. Cic maeh ghdp phii tuin thu quy djnh vd chdng thim nudc v i CO din nhiet.
-Xiyiy bi mat di trang trf. Vide xQ IJ b i mit d i bing each phu mpt Idp bao ve hogc lip diy Id rdng mat, cd ngliTa l i lim ting dp die chic cua nd.
Trong sd nhiJng phuang phap xQ ly b i mit da thi nhQng phuong phip sau day cd the tham khio sQ dung:
_ 1. Son bing logi diu ioing mau khd cd dung mdi dd bde hoi: Diu chui vio trong cac Id ring cua da, diu tic dung vdi d xy trong khdng khi se cQng lai thinh mdt ming bio ve chic va chdng thim. Dung djch thudng dung l i diu pha xang. Nhuoc diem eua phuong phap nay i i : Ldp bao phu biin mau, sim din inh hudng din trang tri kiin triJc.
NGUOI XAY DUNG SO THANG 3 & 4 • 2015
VE NGUYEN NHAH GAY Hlf HAI VA BIEN PHAP XlJf LY BAO VE BA..
2. Trong vung cdng nghiep, d do khdng khi chUa nhiiu sulfurd, ein xQ iy b i mat da bing dung dieh nudc clorua bary. Mudi niy tic dung vdi sulfurd cd mat I m hdi nudc v i chuyin din thinh sulfua bary - dang hat rit mjn, lip cic Id rdng cua d i rit tdt, chit nay khdng bi xim thuc hda hpc v i cd mau tring.
3. Ddi vdi da vdi, ngudi ta thudng diJng dung djch silicat natri (thuy tinh long), hoic diJng dung djch cd hidu qui hon l i dung djch ed chUa flor. Dung dich niy la sin pham eua viec kit hdp giQa florua silicat vdi cic florua kim loat khac - nd ddng vai trd cic mudi hda tan eiJa axit silico - floric (H2SiF6). Cic florua kim logi thudng dupc sQ dyng l i : silico - florua manhddi hoic silico - florua nhdm (MgSiF5; AI2 (SiFe)).
Sau khi xCr 1^ dung djch flor tren d i vdi dudi tic dyng cua dp am v i khf caebonie trong khdng khf se xiy ra mdt logt phan Ong hda hpc glQa cac nhan t i niy (vdi v i flor). Kit qui cua no tao thinh florua canxi (CaFg) va cac "gel" bioxit silicat ngim nudc, hydro-xit manhddi hoic hydroxit nhdm Chit florua canxi rit khd hda tan, cdn cic "gel" cung khd bj hda tan, chiing nhet diy cic Id rdng cua d i , tao khi ning bio vd chdng thim nudc y i khf.
PhUdng phap xQ ly bing dung dich flor l i mdt phuwng phip tdt nhit bio vd d i vdi, d i elm thgch.
4. RUa mit da trang tri bing hoi nudc: trudng hpp mat d i thien nhien dp lit trang tri cdng trinh kiin true bj dpng phu liu ngiy cic byi ban, viec rUa bing nudc td ra khdng cd hieu qui thi dung phucmg phip rCra
bing hdi nudc cho hieu qua tdt. Diy l i mdt phuorig phip duoc chi din sQ dyng ddi vdi cic bd phgn kiin true cd b i mat gia cdng mjn v i cic bd phin d i bj i>
dpng cua cic cdng trtnh ling tam, dii bia Ijch sQ, vl nd hoin toin khdng giy hai ddi vdi ehit lieu trang trf va didu khie.
Vide rOa sgch d i bang hoi nudc duoc thuc hi|n nhd bd thidt bj eip hot nudc bio dam cip hoi nudc vdi ap suit ra d mieng vdi phun l i 1,5-2 at va ning suit l i 3 mVphiit.
Thdi gian nJia tuy thuoc vio mUc do nhiim bin ciJa b i mat, nd dao ddng trung binh trong khoing 6- 10 phut/m=. San phim sau khi kdt thuc qui trtnh riJa ed nhidt dO 25-30''C (nhidt dp b i mat).
Thiit bj cin dung:
- Binh chiu ap Iyc chQa nudc v i hdi ed van diiu ehlnh d hai Id, mpt be c i p nudc vio bmh v i mdt dm^c nil vdi dng din hoi, tit ea diu phii dim bio kin, chit khit.
- dng cao su din hoi, diu ra eua dng duoe ndi v6i vdi thijy tinh hinh cdn...
Binh chUa dupc chUa diy nudc v i dupc dun ndng din sdi v i tao thinh hoi, vdi ap Iyc cin thiit Hd duoc phyt true tiip ldn b i mat cdng trtnh hoic chi tilt kiin true ein rOa saeh.
Tgi b i mat vat the cin rCita, hdi nudc se ngung tu thinh nudc v i cudn theo cic byi bin eua b i mgt da.
De ning cao hieu q u i ciia qui trinh rUa, nguifi la thudng kdt hop ddng thdi phun hoi v& phun nudc co i p lue cin thiit.Q
MQI CON D l / d N G D E U TOll...
(Flip theo tang 38)
lectica, pileritum, plaustrum, raeda, sarraeum, tensa... Ai niy qua ducffig ddu phii tra phi thdng hinh, phi hing hda va nghi tai cic djch quan da sd I i ciJa Nha nudc v i l i mdt cich d l La M i giy quy v i mdrdng lanh tho.
Nhidu con dudng xua vin tdn tgi ddn nay, nhu tai Italia l i dudng Ostiense - Ostia ben ciJra sdng Tiber, dudng Praenestine - Praeneste v i d i ^ g La tinh - Capua hpp gia9 vdi dai Id Via Appia - xa Id cao tdc diu tien eua t h i gidi. Duoc xiy dung nam 312 trudc Cdng nguyen, ndi tU trung tam thinh Rome din thinh phd Brindisi ngay nay. Via Appia dii 563 km, hai bdn rpfp bdng ciy xanh v i nhQng ling tam dd so cua cic vj thanh v i vua chua nhu thinh San Sebastian, San Domitilla, San Callixtus... Mdt phin ciJa Via Appia nim giQa thu dd dupc bao tdn rit cin thin v i trd thinh dja dilm linh thieng thu hiit du ljch.
Doan dudng niy bit diu tU ddi Capitol bing qua quing trudng Idn, ddi Palatine, trudng dua Circus Maximus, khu nhi tim Caracalla... Tai Anh l i dgi 10
Via Fosse ra ddi tU t h i ky thU nhit sau C6ng nguyen dai 290km, ndi Exeter tay nam England vdi Lincoln - Lincolnshire. Noi diy xe cd vin chgy rim rim mdi ngay CQng vdi cic dudng Ermine, VVatling, Via Fosse l i mdt con dudng di sin liu dcri v i dong due nhit cua Anh.
Tuy dudng s i phUc tgp song ngudi La Ma xua lit it khi dung ban dd nhd d i cd su chi din trdn edt mic cung nhu cic sach ljch tnnh. Cd Id vi t h i ban dd La M i rit hidm. Sau hang trim nim, mdi tim thiy mot ban dd trung co thd ky XIII va dUpc sao tQ mOt bin dd quan su La Ma thd ky thU tu. Do dutw Conrad Peutinger - mOt n h i nhan hpe ngudi DUc phit hi§n trong mOt tu vign ndn nd ed tdn l i Bin dd Tabula Peutingeriana. Ong niy d i gin glQnd din nim 1507 thi cho t i i ban. Tabula Peutingeriana dupc ve 6d&
dang mOt cudn thu dai 6,75m rdng 0,34m v i dang dupc giQ tai thu vien Hoing gia Hofburg, Vienna;
ao. Theo dd, midn nam Italia nim d trung tam th§
gidi, Ai Cap nim bdn trii, Syria bdn phit, bien Dja Trung Hii tren cung. Thiy rit nhiiu true dudng ldn cua La Ma bing muc ving vdi nhidu thinh phd va dja dilm nhu sdng hd, nui ddi ndi tidp bing eie bin bii cich quing. Q
LH: 97 ngo 143. pho Cli0 KhSm Thifin, R Trung Phung. e6ng Da, HI NOI. AT: 0945 054 448 Emaii; [email protected] NGUOI XAY DUNG SO THANG 3 & 4 • 2015