1、1850 单词， 9500 英文字符， 2900 汉字 出处： Ding X, Liu W, Ye J, et al. Research of Recycled Bearing Concrete Hollow BlockC/ International Conference on Civil Engineering and Urban Planning. 2012:498-503. 毕 业 设 计（论文） 外文翻译 设计（论文）题目： 学 院 名 称： 建筑工程学院 专 业： 土木工程 学 生 姓 名： 学号： 指 导 教 师： 2014 年 10 月 23 日 1 外文一： Research
2、 of Recycled Bearing Concrete HollowBlock XiaoyanDing*,WenkunLiu*,JihongYe*,ZhongfanChen*,andMingXu* *(SoutheastUniversity,KeyLaboratoryofConcreteandPrestressedConcreteStructuresoftheMinistryofEducation；No.2,SipailouRoad,Nanjing210096；Tel:15051848122) ABSTRACT On the premise of using stone chips, th
3、e paper studies the effect of the replacement level ofrecycledaggregatesandw/conthecompressiblepropertiesofrecycledconcretehollowblocks,thenfindoutthelinear relationship between the ratio of Rk / Rl ( Rk : the compressive strength of recycled concretehollowblock；Rl:thecompressivestrengthofrecycledco
4、ncretecube)andX(thereplacementlevelofrecycledaggregate), provide the theoretical basis to popularization and application of recycled concretehollowblock. KEYWORDS Recycled Concrete； Block； Compressive Strength； ReplacementLevel INTRODUCTION Usingwasteconcretetoprocessofrecycledaggregateforrecycledco
5、ncreteandrecycledconcreteblockhasimportantpracticalsignificanceandbroadprospectthatisavaluablemeasuretoachievetheefficientrecycling of the waste concrete. The domestic research of recycled concrete strength has reached acertaindegreeatpresent.Buttheconclusionthatthestrengthofconcreteblockaftermixing
6、recycledaggregatecan rise are usually inconsistent for difference in these aggregate category. This paper discussesthecompressive strength of recycled concrete hollow blocks (RCB) through the recycled concrete injectedintostone chips of natural aggregates, and seeking for relation between the recycl
7、ed level andcompressivestrength,thustoprovideausefulreferenceoftryingtoimplementtherecycledblocks. EXPERIMENTAL MATERIALS Recycledconcreteaggregate(RCA)wasobtainedfromanoldbuildinglocatedinNanjing.Therecycledaggregate with high water absorption is indisputable (Zhao & Deng 2007 and Xiao 2008).We too
8、kmeasures of RCA to pre-absorb. The crushed concrete was processed to pass through a mechanicalsievingsystemtoproduceandthefinishedaggregateswithparticlesizesof0.16-8mm.Thephysicalpropertiesisin table 1.Cement were sourced from Zhonglian factory in Nanjing, P.O42.5. Table 1. Properties of Recycled a
9、nd NaturalAggregates Properties Natural Recycled Density-SSD2/(kg/m3) 2650 2630 Density-Bulk/(kg/m3) 1500 1370 Porosity/% 43 48 Waterabsorption/% 2.43 5.8 Alkali-aggregate reaction/% 0.006 0.066 Particlesize/mm 28 0.168 Finenessmodulus 2.7 3.2 Stone powdercontent 1.00 0.25 MIX PROPORTIONDESIGN Desig
10、nbasis.Nowadays,wedesigncompressivestrengthofconcreteblockswith150mmcubictestforfoundationinChina.Blocksandconcretespecimensarecomposedofthesamematerials,butthereareanumerousofdifference:Thesizeofblockswithpluralityofholesandatthelevelof25%to50%of 2 hollow is larger than concrete cube which is in a
11、small size. The strength calculation of blocks withgrosssection differ from concrete cube with net section. The diversity of them are in moldingcondition,systemandtimeofvibration,formingnumberandequipmentmaterial,etc.However,thefailuremodeisdistinctfromeachotherforblockswithholeandthin-wallwhilecube
12、withshortcolumns. Usually, the mix design of concrete blocks were summarized as follows (Zhang 2007): Determinetheconversion relationship of compressive strength between block and concrete cube； CalculateW/Caccording to the requirements of strength and durability； Determine water requirement and cem
13、ent quantity on the basis of type and specification of aggregate； The experiment of concrete cubeinaccordancewiththestandardmethodfinishuntilmeetingthedesignrequirements,thencarryonconcreteholeblockstrengthexperiment； Issuewiththemixproportiondesign. Mix proportion determination.The blocks were desi
14、gned with internal dimensions of 360 mm inlength,240mminwidth,and115mmindepth.Therewerefiverowsofholescrossarrangedtheblocks,whichwith dent in short side and plane in long side. The eight mixtures included two control mixture usingonlynatural aggregates, six mixtures with recycled aggregates and the
15、 replacement of natural aggregates wasatlevels from 25 to 100% by weight. All these mixtures were expected to achieve a targetcompressivestrength of not less than 5 MPa at the age of 28 days. According to section 2.1 of the paperandconstruction criterion, concrete experimental strength should be inc
16、reased than the design by 10% to15%.Both two W/C (0.48 and 0.64) in this paper were based on the forming quality of hole block by field testinseveral times. Meanwhile we found RCB were difficult to shape at the aggregate level at 100%.Wesuggestthewaterdoseofconcreteperm3shouldbeconsideredandaddition
17、allevelofwaterabsorptionofrecycledaggregatesisinrangefrom3%to10%.EightgroupsRCBmixproportionusedforblocksweredesigned in this experiment, see Table2. Table 2. Mix Proportions Used forBlocks Type Type W/C RESULTS ANDDISCUSSION Experimentaldetails.TheblockscamefromNanjingSHIHAOBuildingEnergyLimitedCom
18、panyforthe hydraulic vibration molding equipment. The formed blocks were first in a standard curing room for72hours,andthenconditionaltransportedoutoftheconservation.Thetemperatureandrelativehumiditywerecontrolledat20Candnotlessthan90%accordingtothestandardrequirement.Therearefivespecimens in each g
19、roup for a total of 40 specimens. The compressive strength of the block specimenswasdeterminedusingacompressiontestingmachinewithamaximumcapacityof2000kN,accordingtostandard methods(GB/T 4111 1997, 1997). Table 3 shows the results of the compressive strengthofblock specimens, which is given as the a
20、verages of fivemeasurements. Experimentalphenomenondescription.TheexperimentfoundthatdestructivepatternofRCBwerebasicallythesameineverykindofsubstitutionlevel,whichisalmostasthesameasnaturalblocks.Thefailuresurfacestartedfrombondfailureofnatural,recycledaggregateandcement.However,noobviousprecursor
21、to failure is observed prior to the occurrence of instability. At the preliminary stage of load,withload increasing, thesurface RL W NA RA C W RL/ NA RA C W /% /C /kg /kg /kg /kg % /kg /kg /kg /kg RCA1 0 0.48 1845 0 375 180 RCB1 0 0.64 1938 0 375 170 RCA2 25 0.48 1384 461 375 194 RCB2 25 0.64 1453 485 282 195 RCA3 50 0.48 922 923 375 208 BCB3 50 0.64 969 969 282 209 RCA4 75 0.48 461 1284 375 222 BCB4 75 0.64 485 1453 282 224
