管片內(nèi)施工工藝翻譯-中英對(duì)照
我公司目前施工的穗莞深城際軌道項(xiàng)目的管片預(yù)制全部添加采用聚丙烯纖維混凝土（共8000環(huán)，約140000立方米）；另外，我公司施工的天津海河盾構(gòu)項(xiàng)目的管片生產(chǎn)也添加了聚丙烯纖維。
為減少管片制作過(guò)程中開裂，并提高結(jié)構(gòu)耐火能力，防止火災(zāi)情況下，管片混凝土塊爆裂掉塊，每方混凝土內(nèi)摻網(wǎng)狀聚丙烯纖維1.5kg。纖維性能指標(biāo)如下表所示：
聚丙烯纖維指標(biāo)表
項(xiàng)目 指標(biāo) 項(xiàng)目 指標(biāo)
抗拉強(qiáng)度 ≥500MPa 熔點(diǎn) 160¬170℃
彈性模量 ＞3500MPa 抗酸堿性 強(qiáng)
電阻 1.2GΩ 直徑 ≤100μm
韌性指數(shù) I5≥3.0 材質(zhì) 100%聚丙烯，
不含再生鏈烯烴
比重 0.91g/cm3
標(biāo)準(zhǔn) 符合CECS38:2004纖維
混凝土結(jié)構(gòu)技術(shù)規(guī)程
長(zhǎng)度 12¬19mm
施工工藝流程：
a. 管片混凝土采用專用攪拌機(jī)生產(chǎn)，纖維隨骨料沿上料輸送帶一起投入混凝土攪拌機(jī)，每盤摻入3 kg；
b. 為確保纖維在拌合物中分散均勻，不產(chǎn)生結(jié)團(tuán)，先將纖維、水泥、粗細(xì)骨料干拌1-2分鐘；
c. 加水濕拌，較普通混凝土規(guī)定的攪拌時(shí)間適當(dāng)延長(zhǎng)40-60s，以確保纖維在混凝土拌合物中分散均勻，同時(shí)確�；炷撂涠葷M足設(shè)計(jì)要求和規(guī)范規(guī)定；
d. 纖維混凝土澆筑方法應(yīng)保證纖維的分布均勻和結(jié)構(gòu)的連續(xù)性，振搗時(shí)間較普通混凝土延長(zhǎng)20s左右至無(wú)可見空洞為止；
e. 混凝土接近初凝時(shí)（表面比較鈍化時(shí)）方可進(jìn)行抹面，不宜使用過(guò)于毛糙的抹面工具，抹面應(yīng)光滑，但不得加水，不得抹面次數(shù)過(guò)多。
Construction Technology by adding polypropylene fiber into the segment
The prefabricated segments of the construction project of our company in Sueiwanshencheng Tunnel Project all applies polypropylene fiber concrete (8000 rings in total, which is about 140000 cubic meters). In addition, the prefabricated segments production of our company in Tianjin Meihe Tunnel Shield Project has also added the polypropylene fiber.
In order to reduce the craze in production process, and improve the performance of fire resistance of structure, and under the condition of fire prevention, segment of concrete blocks, the concrete of each cubic meter shall be mixed with 1.5 kg mesh polypropylene fiber. Fiber performance indicators are as follows:
Polypropylene fiber index table
Item Index Item Index
Tensile strength ≥500MPa Fusion point 160¬170℃
Elastic modulus ＞3500MPa Acid and alkaline resistance Strong
Resistance 1.2GΩ Diameter ≤100μm
Toughness index I5≥3.0 Material 100% polypropylene;
no regeneration olefins chain content;
Specific gravity 0.91g/cm3
Standard Meet with the standard of CECS38:2004 Technical specification for fiber concrete structures
Length 12¬19mm
Construction process:
A. Segment concrete applies special mixer in production; fibers shall be dumped into the concrete mixer together with aggregate on feeding conveyor belt; each disc mixed with 3 kg;
B. To ensure that the fiber is evenly distributed in the mixer without clot, mixes the fibers, cement, coarse and fine aggregate for 1-2 minutes without water;
C. Add water to the mixer, mixes for more 40 to 60 minutes than normal concrete mixing time, so as to ensure that the fiber is evenly distributed in concrete mixing. At the same time, ensure concrete slump meets the design requirements and regulations;
D. Fiber concrete casting method shall ensure the uniformity distribution of fibers and continuity of structure; the vibrating time shall have more 20 minutes than ordinary concrete until no empty hole were found;
E. Carry out the plastering work when concrete close to initial setting (concrete surface is inactivation); do not use rough plaster tools; plaster surface shall be smooth; do not add water and do not plaster for too many times.
2013.10.22