Cau 3:

Xd ham luong Ca(OH)2? V= 1340 kg/m3; ρCa(OH)2= 2,05 kg/l; ρn= 1 kg/l

Bai giai:

Xet 1m3 voi nhuyen

He pt: mCa(OH)2 + mH2O =1340 (kg)

          VCa(OH)2 + VH2O= 1000 (lit)

↔ mCa(OH)2+ mH2O =1340

     mCa(OH)2/ ρCa(OH)2+ mH2O/ ρn =1000

↔  x+y=1340

                x/ 2,05 + y/ 1 =1000

↔ x= 663,8 kg

     y= 676,2 kg

Vay mCa(OH)2=663,8kg

Ham luong Ca(OH)2 la 663,8/1340.100%= 49,5%

Cau 1: KL rieng cua VLXD:

1/ D/n: La kluong cua 1 don vi the tich o trang thai dac hoan toan

2/ CT:

ρ= m/Va

m: klg cua vat lieu

Va: the tich cua VL o trang thai dac hoan toan

Don vi ρ (g/cm3; T/m3)

3/ Phuong phap xac dinh:

+ Doi voi VL dac hoan toan: - VL co hinh dang xac dinh: can, do mau

                                              - VL co kich thuoc ko xd: can va xac dinh V bang cach the tich chat long chiem cho

+ Doi voi VL rong: nghien den co hat <0,2mm

Can khoi luong va do V bang binh do the tich

+ Doi voi VL co hat be (cat, xi mang…): phuong phap binh ty trong

4/ Y nghia:

- Phan loai cac VL voi nhau: cac VL cung loai co KL rieng tuong tu nhau

- Phan doan truoc 1 so tinh chat cua VLXD

- Tinh toan thanh phan cua 1 so loai VL

Cau 2: Tinh deo va tinh qua’nh cua bitum dau mo~

Tinh deo

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1/ K/n: la tinh chat dac trung cho kha nang bien dang cua bi tum duoi t/d cua ngoai luc

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2/ Cac yeu to anh huong

- Nhiet do: t°↑ → deo tang

                  t°↓→ deo giam → bitum tro nen gion

- Thanh phan nhom:

Dau, nhua nhieu → deo ↑

- Thoi gian su dung: thoi gian su dung lau → deo ↓

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3/ Phuong phap xac dinh:

danh gia bang do keo dai va xac dinh bang dung cu keo dai

Dung nong chay bitum, rot vao khuon so 8 de nguoi trong phong, dua vao dung cu keo dai, toc do keo 5cm/ph

L lon → deo cao

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4/ Y nghia

Quyet dinh cong nghe che tao vat thi cong VL

Tinh qua’nh

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- La tinh chat dac trung cho kha nang chong lai su chuyen dich cua cac hat bi tum duoi t/d cua ngoai luc

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- Nhiet do cua moi truong

t°↑ → nhom chat nhua bi chay long → do quanh ↓

- Thanh phan nhom:

Nhom chat dau, nhua nhieu → quanh ↓

Nhom afan, cuben, cacbonic ↑ → quanh ↑

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- Dung chi tieu do cam sau cua kim

Dun bitum nong chay, do vao khuong de nguoi o t° phong → got be mat bang dao thep, tha kim roi 5s → do cam sau cua kim lon → tinh quanh cao

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Do nho trong pham vi rong → anh huong nhieu den cac tinh chat co hoc cua hon hop VL, kha nang chat voi chat ket dinh, dong thoi quyet dinh cong nghe che tao vat hi cong VL