- CAu thang hinh thdc ban dAm : K6t c6u chju lqc c6 2 phAn : bhn va dAm nghi&ng (dAm lim6ng). Cung co thd c6u tao ban va b$c thang thanh mat khSi, Iuc nAy b$c thang gidng nha m$t dAm nh6 tqa tr6n dAm nghieng, dam nghieng tga l&n dAm chidu nghi. Quail he giiia bin, bijc va ddm nghisng co mgy trairng hdp sau : + Bin, b$c d phia tr&n dAm, v& phamg diqn chju lqc kdt cgu hdp ly, nhmg d$m 16 xudng phia d~di nhi&u. + Bhn, bijc d$t 6 phia dadi dAm, nha v$y tr6n phsng, dep, d6 lam v$ sinh. + Bhn, b$c dst 3 gida ddm : Tuy tinh hinh cu th6 in6i thin thang co th6 b6 tri mot dAm chju ban b$c : dAm cllju mat dAu, dAu kia ciia ban b$c k& vao tUirng, host the0 kQt cau co~lsole Inat ddin hoQc 2 d&in dgt 6 gida ban b$c. (H6-33) VI1 Cau tao bo ph&n bao ve : 11- La11 can - tay vin : (H6-38) 1.1- Mo ti : Lan can, tay vjn 18 bo ph$n cgu tao d6 bao dim an toan cho nguai di lai va thoai mrii khi sir dung. No co th& dung vgt lieu bang go, d6ng thau, thtp, chat d6o vB betong cot thCp. VC hinh thirc c6 th& la lan can dac hoac Ian can r8ng : - Lan can dgc : Thbng thuhg Ihm bing bCtdng, gach. Khi Iim bang bCt8ng thuhg neu ciiu kien toin kh6i thi c$n dd liCn vdi than thang. Neu Ihm b5ng gach thuhg bing 114 gach, d6 b60 dam do cdng can phii gia c6 bbi cic giang b$t8ng cot thtp the0 chi&u doc Ian can. - Lan can rong thoang thuhg 1hm bing kim loai, g18 : Lan can loai nay thoang nhe, trang tri the0 nhieu hinh thirc, nhung phAi dHm bAo dugc an tohn v6i c6c khoing tr6ng khong duqc lh hm 15cm (khoang cho dAu nguai chui lot). 1.2- Lien ket tay vin vao Ian can, Ian can vao than thang : Tay vln duqc 1hm bang nhi&u loai v+t lieu : go, dong, thCp, nhbm, granito Tilt ci vat litu niy cdn bao dim nhan, khang b6m bui nhieu. Lien ket cc6 th6 bang dinh, dinh vit, hhn hoac liCn k&t tohn kh6i : Lien ket Ian can vio thin thang : + Khi che tao thin thang c$n chila sZn 118, sau khi Ihp Ian can vio, 16 duqc tr6m kin bang v3a ximang. + Li$n k6t hhn : khi thanh chong Ian can bang thtp ong, b bAn bgc chbn s%n nhkg thCp ban, sau d6 hhn ong sat vao. co hinh thuc nhe nhang. 1.3- Xir 19 chb xoay chuy6n hrrdng clia tay vjn Ian can : ThBng thubng d6i vdi c8u thang 2 ve" hay nhi$u ve" thi dubng truc Ian can tay vin dugc dQt song song vdi dbn thiin thang. * Cac xir ly : - U6n cong tay vin, giim chi&u siiu, giAi phap nay 1gi kh6ng gian, nhung gia c8ng kho. - Mb r$ng chi& nghi hoQc b6 tri b$c so le b chi& nghi. - Kh6ng lam song song vdi dh thang giii phap nay chi dung cho cac c8u thang phu. 2)- M4t b@c va miii b@c thang : (H6-39) 2.1- Hinh thdc b8o ve mfii b@c : Dung vira xi mang hoQc cac loai vat lieu it bi mai mbn lam moi b$c, c6 the" lam vat hoQc lugn trbn d$ khi budc kh6i bi vip. 2.2- M$t b@c thang c6 b8n gidng nhrr m$t san : - MQt b@c lang v8a xi milng mac 80- 100 day 20 mm, hay trit granito. De" ch6ng trugt, trCn mQt b@c nCn lam gb b5ng vat lieu it bi mbn (cabonrundum). - Mat b@c 1at : gach hoa, da cim thach, tim cao su, chit dCo. can lung cac . Dl5 urn). ~inh 6,3a TH&N THANG . liCn vdi than thang. Neu Ihm b5ng gach thuhg bing 114 gach, d6 b60 dam do cdng can phii gia c6 bbi cic giang b$t8ng cot thtp the0 chi&u doc Ian can. - Lan can rong thoang thuhg 1hm bing