外文翻译----克拉斯诺亚尔斯克水电站大坝大体积混凝土温度控制.docx

附录：英文原文temperature control of the massive concreteof the krasnoyarsk hydroelectric station dama. p. dolrnatov and s. z. neidlin udc 627.821.2 : 666.972.021.21.035.83(282.251.2)during recent years a number of large hydroschemes with high massive concrete dams have been bnilt in areas of the ussrin an area of extreme climate. a number of problems arise in the erection of massive dams under severe climatic conditions related to the prevention of fissuring in the concrete and obtaining a monolithic structure.typical features of the construction of large hydroschemes are the large volumes of concrete and the extremely limited time for pouring them, which means a high rate of concrete placing.measures for controlling the temperature of the concrete on a large scale were adopted practically for the first time in the soviet union in the construction of the krasnoyarsk hydrocomplex. the severe climatic conditions at the site (mean annual temperature +0.4, maximum long range temperature +37 and minimum, -54) introduced serious difficulties in obtaining monolithic mass structures and ptaced special demands on the concrete and its placement. in order to obtain monolithic concrete structures,the technical regulations for carrying out concreting lays down the following temperature conditions for blocks with columnar section (plan dimensions 15 x 11.5 m, height 3 to 9 m):a) maximum temperature in blocks placed on fresh concrete (less than 1 month old) must not exceed 40;b) maximum temperature in blocks placed on old concrete (more than i month old) and rock must not exceed 28;c) the temperature drop between the core and faces must not exceed 23;d) temperature of the concrete at the moment when the intercolumnar construction joints solidify (cementation) must not be more than 5 in the bottom 20 meters from the foundation and 8 in the remaining mass.a number of measures were envisaged for controlling the temperature of the dam concrete, namely: the use of cements with average thermal properties (mineralogical composition of the clinker c3s = 47-48%; c3a = 6-6.5%; heat liberation of the slag portland cement (40% slag) on the 28th day 73-75 kcal/kg); zonal placing of the concrete; the use of heated formwork (from 15 september to 15 april) keeping the blocks stripped in winter only under heated covers and using three types of formwork depending on the concreting season, with coefficients of heat transfer k = 0.8, 1.5 and 3.0 kcal/m2hdegree; prior cooling of the concrete; and cooling by cold water circulating through coils laid in the concrete.fissuring was markedly reduced by these measures. while in 1961 there were three cracks per 1000 m3 a concrete, 1.24 in 1962, 1.12 in 1963, and 0.42 in 1964,there were only 0.16 in 1965. the number of cracks rose slightly in 1967 on account of a smaller proportion of cooled concrete and the higher grading of the concrete on the top sections of the structure.table 1 sets out the main cooling characteristics of the concrete to temperatures at which cementation of the joints could be undertaken.piped cooling for reducing the peak of the exothermic temperature rise of the concrete was brought into use during the summer of 1963 and employed generally from 1964. during this period there was a sharp drop in the fissuring rate in the concrete. during 1961 to 1963 the concrete in the spillway apron and the crest of the first stage was not cooled and at the same time the temperature rise of the concrete masonry was limited by reducing the height of the blocks near the rock to 0.7-1 m and by the small growth of the structures in height. concrete placing in the second-stage excavation and in the first-stage excavation was carried out above the crest using piped cooling.the numerator shows the amount of concrete placed or cooled during the year; the denominator shows the volume and increase in the amount.200,000 m s of this concrete was cooled using water cooled in a refrigeration plant.concrete placing in the top section of the dam, which is intended for completion by 1969-1970, will be carried out without artificial cooling.cooling of the concrete during the construction of the krasnoyarsk hydroelectric station was carried out in two stages. in the first stage cooling was used for reducing the exothermic peak of the freshly placed concrete and in the second stage for further cooling of the mass down to the temperature where it is made monolithic.first stage cooling was carried out usually in the summer only but from 1965, with the introduction of high blocks, it was carried out in winter. from 1966 the first stage cooling was carried out continuously for the purpose of improving the concrete stress in the immediate vicinity of the cooling pipes, accelerating cooling of the block, for rendering the joints between columns monolithic and improving reliable performance of the cooling coils (leaching).the second stage usually starts at the end of august with a water temperature of 15-18. during this period the concrete is cooled mainly from a temperature above 25-30, for the purpose of further reducing the temperature towards the winter season and in preparation for cooling in winter with water at a temperature of 0.5-1. beginning in november, cooling is started on the whole remaining concrete mass directly prepared for grouting the construction joints (temperature of the blocks in the order of 20-30). the times for cooling the zones am governed by the separations between the pipes and coils in the given zone. hence, the use of coils with different pipe spacings on the one zone is undesirable unless this is necessary for observing the temperature conditions. in order to observe the technical specifications which allow a temperature drop between the cooling water and the concrete masonry not exceeding 20-22 during the winter season, blocks with a temperature 35-40 are successively connected for cooling through the coils of the adjacent blocks. the number of blocks connected up in sequence depends on the temperature of the concrete and of the cooling water and the cooling water rate, and can be readily determined experimentally and by calculation 1. table 2 sets out theoretical data on cooling of concrete during the second stage, confirmed by full-scale investigations.fig. 1. temperature rise of the concrete with pipe cooling of a block 1.5 m high. 1, 2, 8) temperature-rise curves for the concrete in blocks 40-viii, 40-vi and 40-v; 4) temperature-rise curve of the concrete according to calculation; 5) temperature-rise curve of the concrete calculated on the basis of the vsn-02-64 reeommendalions,e) remote thermometers; o) cooling pipes.during construction an experiment was carried out for increasing the design critical cooling waterconcrete temperature drop to 25-30 water at a temperature of 0.5 was passed through the mass concrete members (temperature 32 five concrete members were used in the experiment, with across-section 1.5 x 1.5 m. neither the remote-recording instruments in the zone of the cooling pipe nor visual inspection recorded cracks in the immediate vicinity of the pipe. foreign experience 2 also points to the absence of cracks in the zones of the cooling pipes. from the results of this experiment it was possible in the second stage to increase in advance the temperature drop between the cooling water and the concrete to 25 raising the cooling efficiency to 10-20%.pipe cooling in practice proved a basic and effective measure for controlling the temperature conditions of the concrete. depending on the season, the seasonal technical conditions for controlling temperature conditions were applicable in the construction, taking into account the variations in temperature of the concrete mix and of the concrete of the main block. as indicated by numerous full-scale observations, the maximum exothermic temperature rise in the core of the block with height not less than 5 m is 29 1 (with a slag portland cement rate of 240 kg/m3). there was no difficulty in obtaining the required temperature conditions for any height of block during the period from october through may, since the temperature of the concrete mix could be held below 1012 without difficulty during this period. hence, the temperature conditions of the concrete when placing on a new base were maintained over the whole volume. when placing concrete on an old base the height of the blocks has to be reduced to 2-3 m or cooling has to be applied during concreting with separations between the pipes of the coil horizontally and vertically 1.5 m at the 0.5 and 3 m levels. from june to september when the temperature of the concrete mix is between 16 and 22 the cooling coils must be situated over the height of the block at the 0.5 m, 3.0 m and so on levels when piacing the concrete mix and at 0.5, 1.5, 4.5 m and so on when placing on an old base.table 3 sets out data relating to reduction in the exothermic temperature rise in blocks with height greater than 5 m.there are at present several similar methods for calculating pipe cooling in the first and second stages 1, 3. numerous comparisons of theoretical data on pipe cooling with results of actual observations have indicated that this procedure 1, 3 is in good agreement with the experimental data on cooling in the second stage (disregarding the exothermic temperature rise).cooling of concrete in the first stage, particularly in high blocks, proceeds under natural conditions 15-20% more effectively 5. this is on account of the lower rate of heat liberation of the cement due to the lower temperature of the concrete near the cooling pipe.fig. 2. relative temperatures in the center of the block from the exothermic temperature rise with pipe cooling. ) cooling of the concrete placed on an infinite base; . . . . ) with three-day interruption of concreting. 1) relative temperature without pipe cooling; 2)the same with spread of coils 1.5 x 0.75 m; 3) the same with spread of coils 1.5 x 3.0 m; 4) the same with spread of coils 1.5 x 1.5m; 5) the same with spread of coils 1.5 x 0.75 m.fig, 3. costs for pipe cooling of concrete (rubles/m3). 1) capital costs; 2) operating costs; 3) total costs,s) area of acion of i linear meter of cooling coil pipe, m2; a) coil pipe.calculations of pipe cooling with interruptions of more than five days in concreting for blocks less than 1,5-2 m high by the procedure 3 using curves for the e coefficients of the mass under exothermic conditions lead to a substantial error. the efficiency of pipe cooling is exaggerated 2-3 times as compared with actual results. by way of example fig. 1 shows theoretical results and actual observations on blocks 1.5 m high with a 10-day interruption in concrete placing (slag portland cement content 220 kg/m3). curves 1, 2, and 3 show, respectively, the temperature rise of the concrete in the center of block 40-viii (temperature of the concrete mix tcm= 14, base temperature t b = 19, surface temperature t s = 9 without pipe cooling), for block 40-vi (tcm = 16, t b = 24, t s = 16, cooling water temperatures t w = 6), and block 40-v (tcm =17, t b = 22, t s = 16, t w = 80).the cooling pipes were placed along the base of the block before placing the concrete, with a horizontal separation 1.5 m. curves 4 and 5 show the theoretical concrete temperatures on the basis of analytical calculation and according to the recommendations of vsn-02-64 3. when comparing curves 2 and 3 it is seen that the temperatures in blocks 40-vi and 40-v are practically identical for fairly similar initial and boundary conditions. when comparing the results for blocks 40-viii (without artificial cooling) and 40-vi and 40-v (with pipe cooling) account has to be taken of the difference in the base temperatures, providing a calculated correction for the center of the block without cooling of 3.85. comparison of the maximum temperatures of the blocks indicates that according to actual observations the overall effect of cooling amounts to 12.8 + 3.85-11.8 (12.8) = 4.85 (3.85) and from calculation: a) the effect is assessed from curve 5 as 12.8 + 3.85-8.7 = 7.95; b) from curve 4 it is 12.8 +3.85-12.3 = 4.35. it can be seen from this example that calculation by the vsn-02-64 procedure results in an error of 3.1 (4.1) as compared with the actual results. it should be noted that according to the calculations by this. procedure the effect of exothermtc heat taken off by pipe cooling is greater by a factor of almost 3 as compared with actual conditions. analytical calculation of the block considering natural cooling and pipe cooling is very tedious (despite the good accuracy) (curve 4). the following approximate calculation for the peak temperatures can be recommended for adequate accuracy (up to 10% error) and simplicity: a) calculation of the temperature of the layer from natural cooling (analytical or graphical methods); b) calculation of the difference between the temperatures in the block without cooling and with pipe cooling under adiabatic conditions according to vsn-02-64; c) deterruination of the final result as the difference between temperature a) and b).for cooling calculations in the first stage, when the pipes are placed only along the base of the concreted block, the zone of action of the pipe along the vertical must be taken as equal to twice the height of the block (overlapping the subsequent layer).a. p. dolmatov and s. z. neidlinfigure 2 shows maximum temperatures in the center of the blocks obtained on the basis of analytical calculations considering pipe cooling and natural setting of the blocks when placing concrete in one block on an infinite base and when concreting blocks with a three-day interruption. it is seen from the curves that cooling efficiency rises with increasing height of the block and increasing rate of concreting.when assessing the economic efficiency of installing coils with different pipe. separations horizontally and vertically in the second stage of cooling, it can be stated that the most economical is a spread 1.5 x 3.0 m (fig. 3). when calculating the economic efficiency, account was taken of the total operating and capital costs for different pipe spreads; the cost of cooling water was taken from its actual cost in constructing the krasnoyarsk hydroelectric station, equal to 0.024 rubles/m3; the cost per 1 m3of concrete was taken as 22 rubles. it should be also noted that the spread indicated (1.5 x 3.0 m) provides successful cooling of the concrete in the second stage, reducing the cooling time to half as compared with the cooling time for a pipe spread 3.0 x 3.0 m. in practice this requires no cooling plant since cooling can be carried out in this case using river water, available for 200 days at the construction site (leaving out the summer season).conclusions1. pipe cooling of the concrete was successfully employed in the construction of the krasnoyarsk hydroelectric station, being an effective means for controlling the temperature conditions of the mass concrete.2. by employing artificial cooling of the concrete and using cements of average thermal properties for the concrete it was possible to substantially reduce fissuring in the mass concrete from 1964.3. under the conditions of the krasnoyarsk hydroelectric station construction, the most effective pipe spread for the cooling coils was 1.5 x 3.0 m. when placing the concrete in high blocks (over 3 m) on an old base in summer, in order to obtain a quicker reduction in temperature on the concrete in the second stage of cooling (to bring the concrete temperature down to the joint sealing temperature),smaller spaces were necessary between the cooling pipes both horizontally and vertically.4. the use of a pipe cooling system for lowering the maximum concrete temperature with low rate of growth of the structure and block height less than 2 m has little effect and can be recommended only on the basis of the conditions of block preparation for the second stage of cooling, when the concrete temperature in the columns must be lowered sufficiently for carrying out high-grade grouting of the joints between the blocks.literature cited1.m. s. lamldn, practical method for calculating cooling of concrete masses by a system of pipes, nauchno-tekhnicheskii informatsionnyi byulleten, no. 2, leningradskogo politekhnicheskogo instituta (1959).2.b. k. frolov, controuing the temperature conditions of the concrete in the construction of dams in russian,izd-vo energiya (1964).3.vsn-02-64, tentative instructions for pndering monolithic concrete hydraulic engineering structures erected in areas of severe continental climate in russian, izd-vo energiya (1964).4.g. n. danilova and n. a. buchko, method for calculating the temperature conditions with pipe cooling of dam concrete masonry, gidrotekah. stroitel., no. 5 (1965).5.a. p. epifanov and a. p. dolmatov, cohereting the dam of the krasnoyarsk hydroelectric station with high blocks, energeticheskoe stroitelstvo, no. 6 (1966).6.a. p. epifanov and i. a. petrova, requirements on temperature conditions of massive blocks of columnar section poured on a concrete base of variable ages, gidrotelda. stroitel., no. 8 (1967).英文译文克拉斯诺亚尔斯克水电站大坝大体积混凝土温度控制作者：a.p. dolrnoatov s. z.neidlin 华联627.821.2：666.972.021.21.035.83（282.251.2）近年来，在拉斯被极端气候覆盖的部分地区修建了很多包含高品质、大规模混凝土大坝在内的大型水电计划。受恶劣的气候条件影响，混凝土大坝的修建在预防混凝土裂缝并获得的完整的结构这一阶段出现了很多问题。大型水电计划建设的典型特征是需要砌筑大体积混凝土。为了满足极短的浇筑时间要求,混凝土应快速浇筑。大规模混凝土的温度控制方法第一次实际被正式采用是在苏维埃联盟建设克拉斯诺亚尔斯克大坝时。当地严峻的气候条件（年平均温度为+0.4,最高温度为+37,最低温度为-54）使获得完整的宏观结构、满足特定的功能要求及其定位困难重重。为了获得稳定统一的混凝土结构，混凝土技术法规针对柱状节块（平面尺寸：1511.5m,高39m）的温度条件做了如下规定:(a) 新型混凝土（放置少于一个月）内部最高温度不超过40；（b）搁置久的混凝土块和岩石内部最高温度不超过28；（c）混凝土内外温度差不超过23；(d)在混凝土柱间施工缝固化（胶结）时，其温度在离地基20米处不得超过5,其余的不超过8。人们