《地下工程混凝土防水抗渗等级选用探讨.doc》由会员分享，可在线阅读，更多相关《地下工程混凝土防水抗渗等级选用探讨.doc（52页珍藏版）》请在三一文库上搜索。
1、地下工程混凝土防水抗渗等级选用探讨地下防水 2010-06-29 21:13:38 阅读157 评论0 字号：大中小订阅 （此文按作者发表于PKPM新天地2003年第4期对（GB50007-2002）的一点质疑修订而成） 在我国现行的多种结构设计规范中，地下工程混凝土防水抗渗等级的选用有多种规定。有的规定甚至比较混乱，使得设计人员在应用时感到无所适从。本文对多本有关设计规范的相关规定进行了探讨，试图对地下工程混凝土防水抗渗等级的选用找到比较合理的途径。 首先我们来看看建筑地基基础设计规范GB 500072002。该规范的第8.4.3条是这样写的：“筏形基础的混凝土强度等级不应低于C30。当有地
2、下室时应采用防水混凝土，防水混凝土抗渗等级应根据地下水的最大水头与防渗混凝土厚度的比值，按现行地下工程防水技术规范选用，但不应小于0.6Mpa。” 翻开现行地下工程防水技术规范GB 501082001第4.1.3条，它是黑体字，强制性条文，这样写道：“防水混凝土的设计抗渗等级应符合表4.1.3的规定。” 表4.1.3 防水混凝土设计抗渗等级 工程埋置深度(m) 设计抗渗等级 10 S6 1020 S8 2030 S10 3040 S12注：本表适用于IV、V级围岩（土层及软弱围岩）。 山岭隧道防水混凝土的抗渗等级可按铁道部门的有。 可见，现行地下工程防水技术规范GB 501082001（以下简
3、称新防水规范）已经将旧地下工程防水技术规范GBJ 10887（以下简称旧防水规范）规定的按最大水头与防水混凝土厚度的比值来确定混凝土的设计抗渗等级改为按工程的埋置深度来确定混凝土的设计抗渗等级。 旧防水规范第3.1.1条是这样的：“防水混凝土的抗渗能力，不应小于0.6Mpa。 防水混凝土的抗渗等级，应根据防水混凝土的设计壁厚及地下水的最大水头的比值，按表3.1.1规定选用。” 表3.1.1 防水混凝土抗渗等级 最大水头(H)与防水混凝土壁厚(h)的比值 (H/h) 设计抗渗等级 (MPa) 35 2.0 让我们再翻开高层建筑混凝土结构技术规程JGJ 32002，第12.1.9条：“当有防水要求
4、时，混凝土抗渗等级应根据地下水最大水头与防水混凝土厚度的比值按表12.1.9采用，但不应小于0.6Mpa”。而高规的表12.1.9即是旧防水规范的表3.1.1，这里不再详细列出。 在很多情况下，按这新旧两本规范选用的设计抗渗等级会有很大差异。建筑地基基础设计规范GB 500072002（以下简称基础规范）比新防水规范晚施行了3个月，而高层建筑混凝土结构技术规程JGJ 32002(以下简称高规)更比新防水规范晚施行了9个月，不应该有这种错误发生。 如一个5m深的地下室，上置500mm厚的覆土，即工程埋深为6m。若墙厚采用300mm厚C30的防水混凝土，在通常土压力作用下是算得下来的。按旧防水规范
5、，H/h=16.67，其值在1525范围内，应采用S12的设计抗渗等级。若按新防水规范，工程埋深H=6m10m，则只需采用S6的设计抗渗等级。可见同一个工程按新旧防水规范选用防水混凝土的抗渗等级差别很大。基础规范这么简单的一句话，会使防水混凝土的设计抗渗等级选用造成如此大的差异。 在给水排水工程构筑物结构设计规范GB500692002（以下简称给排水规范）中，混凝土抗渗等级也是按最大作用水头与防水混凝土厚度的比值来确定的，但其数值却做了修改。它第3.0.3条是：“构筑物混凝土的抗渗等级要求应按表3.0.3采用。”在旧规范给水排水工程结构设计规范GBJ 6984中给出的混凝土抗渗等级选用表与旧防
6、水规范相同。可见，新防水规范的观点已经被给排水规范所采纳。 表3.0.3 混凝土抗渗等级Si的规定 最大作用水头与混凝土壁、板厚度之比值iw 抗渗等级Si 30 S8注：抗渗等级Si的定义系指龄期为28d的混凝土试件，施加iX0.1Mpa水压后满足不渗水指标。 同样条件，如一个5m深的水池，上置500mm厚的覆土，即工程埋深为6m。若池壁采用300mm厚C30的防水混凝土，在水压力和通常土压力作用下是算得下来的。按给排水规范，H/h=16.67，其值在1525范围内，也只需采用S6的设计抗渗等级。 2003年版的全国民用建筑工程设计技术措施 结构中，则采取了和事老的态度。它的第3.1.11条是
7、这样的，钢筋混凝土地下室基础结构防水混凝土的抗渗等级采用新防水规范的第4.1.3条，却也可按高层建筑混凝土结构技术规程JGJ 32002第12.1.9条执行。并且将两个表格均列了出来。按上述例子，让工程设计人员如何确定混凝土的抗渗等级呢？ 那么，新防水规范为什么改用按工程的埋置深度来确定混凝土的设计抗渗等级呢？以前我们设计这样的工程时，按旧防水规范选用S12防水混凝土，施工单位一直是叫苦不迭。这样高的抗渗混凝土无法搅拌、施工质量难以保证等等。可我们设计人员却只能坚持“原则”，不降低混凝土的抗渗等级。新防水规范修订时也正是注意到了这样的问题：设计抗渗等级过高（如S12），不仅仅导致了工程造价的提
8、高，而且由于水泥用量的大量增加，使混凝土硬化时的水化热也大量增加，如果相应的施工措施跟不上，反而使混凝土更易产生裂缝，从而导致工程渗漏。根据我国近十年的工程经验，改按工程的埋置深度来确定混凝土的设计抗渗等级是完全可以满足工程抗渗要求的（详见防水规范的条文说明）。我们现在设计这样的工程只采用S6设计抗渗等级，施工单位求之不得。 此外，在应用防水规范时往往会忽视这样几个问题，借此一并提出供同行借鉴。1、规范第4.1.4条规定：“防水混凝土结构底板的混凝土垫层，强度等级不应小于C15”。有些设计人员往往误把垫层砼设计成C10。2、规范第4.1.6条规定：防水混凝土结构，结构厚度不应小于250，裂缝宽
9、度不得大于0.2（并不得贯通），迎水面钢筋保护层厚度不应小于50。有时设计人员也会忽视，如有的将防水混凝土墙（板）设计成200，有的设计迎水面钢筋保护层厚度不够，还常常忽视防水混凝土的裂缝计算等。3、规范第4.1.2条规定：“防水混凝土的施工配合比应通过试验确定，抗渗等级应比设计要求提高一级（0.2MPa）”。如果设计没有特别提示，施工单位往往没有将混凝土的抗渗等级提高一级拌制。 而在设计水池时，按给排水规范和中国工程建设标准化协会标准给水排水工程钢筋混凝土水池结构设计规程CECS 138：2002，与一般地下工程的要求略有不同。1、抗渗混凝土的最小强度等级可采用C25；2、混凝土垫层的强度等
10、级可采用C10；3、水池池壁及底板厚度最小可采用200；4、混凝土构件的最大裂缝宽度对清水池可控制在0.25mm，对污水池控制在0.20mm；5、钢筋保护层厚度清水池为30mm，污水池为35mm；6、如上例混凝土抗渗等级的选取与新防水规范差不多。另外，对于严寒或寒冷地区，外露的混凝土结构还有防冻要求，可按给排水规范给出的表格选用混凝土的抗冻等级。 以上为笔者在应用新规范时发现的问题和体会，供同行探讨。参考文献：建筑地基基础设计规范GB 500072002，中国建筑工业出版社，2002年3月第一版地下工程防水技术规范GB 501082001，中国计划出版社，2001年11月第一版地下工程防水技术
11、规范GBJ 10887，中国计划出版社，1989年4月第一版高层建筑混凝土结构技术规程JGJ 32002，中国建筑工业出版社，2002年7月第一版给水排水工程构筑物结构设计规范GB500692002，中国建筑工业出版社，2003年2月第一版（英文版 ） Two regulations promulgated for implementation is in the party in power for a long time and the rule of law conditions, the implementation of comprehensive strictly strategi
12、c plan, implementation in accordance with the rules and discipline to manage the party, strengthen inner-party supervision of major initiatives. The two regulations supporting each other, the adhere to a positive advocate, focusing on morality is of Party members and Party leading cadres can see, en
13、ough to get a high standard; around the party discipline, disciplinary ruler requirements, listed as negative list, focusing on vertical gauge, draw the party organizations and Party members do not touch the bottom line . Here, the main from four square face two party rules of interpretation: the fi
14、rst part introduces two party Revised regulations the necessity and the revision process; the second part is the interpretation of the two fundamental principles of the revision of laws and regulations in the party; the third part introduces two party regulations modified the main changes and needs
15、to grasp several key problems; the fourth part on how to grasp the implementation of the two regulations of the party. and revised the necessity and revised history of the CPC Central Committee the amendment to the Chinese Communist Party members and leading cadres honest politics several guidelines
16、 and column 1 by 2015 to strengthen party laws and regulations focus. Two party regulations revision work lasted a Years, pooling the wisdom of the whole party, ideological consensus, draw historical experience, respect for the wisdom of our predecessors, which reflects the unity of inheritance and
17、innovation; follow the correct direction, grasp the limited goals, adhere to the partys leadership, to solve the masses of the people reflect a focus on the problem. The new revision of the and , reflects the partys 18 and the eighth session of the third, the spirit of the fourth plenary session, re
18、flecting the experience of studying and implementing the General Secretary Xi Jinping series of important speech, reflects the partys eighteen years comprehensive strictly practice. (a) revised two regulations of the party need of in based on revised, the promulgation and implementation of January 2
19、010, to strengthen the construction of the contingent of leading cadres play an important role. But with the party to manage the party strictly administering the deepening, has not been able to fully meet the actual needs. Content is too complicated, eight prohibition, 52 are not allowed to hard to
20、remember, and also difficult to put into practice; the second is concisely positive advocated by the lack of prohibited provisions excessive, no autonomy requirements; the third is banned terms and discipline law, both with the party discipline, disciplinary regulations repeat and Criminal law and o
21、ther laws and regulations repeat; the fourth is to clean the theme is not prominent, not for the existing problems, and is narrow, only needle of county-level leading cadres above. is in 1997 based on revision, in December 2003 the promulgation and implementation, to strengthen the construction of t
22、he party play very important role. Along with the development of the situation, which many provisions have been unable to fully meet the comprehensive strictly administering the practice needs. One is Ji law, more than half of the provisions and criminal law and other countries laws and regulations
23、Repetition; two is the political discipline regulations is not prominent, not specific, for violation of the party constitution, damage the authority of Party Constitution of misconduct lack necessary and serious responsibility to pursue; third is the main discipline for the leading cadres, does not
24、 cover all Party members. Based on the above situation, need to and the two is likely to be more relevant regulations first amendment. By revising, really put the authority of Party discipline, the seriousness in the party tree and call up the majority of Party members and cadres of the party consti
25、tution of party compasses party consciousness. (II) two party regulations revision process the Central Committee of the Communist Party of China attaches great importance to two regulations revision . Xi Jinping, general books recorded in the Fifth Plenary Session of the eighth session of the Centra
26、l Commission for Discipline Inspection, on the revised regulations made clear instructions. According to the central deployment, the Central Commission for Discipline Inspection from 2014 under six months begin study two regulations revision. The Standing Committee of the Central Commission for Disc
27、ipline Inspection 4 review revised. Comrade Wang Qishan 14 times held a special meeting to study two regulations revision, amendment clarifies the direction, major issues of principle, path and target, respectively held a forum will listen to part of the province (area) secretary of the Party commit
28、tee, Secretary of the Discipline Inspection Commission, part of the central ministries and state organs Department The first party committee is mainly responsible for people, views of experts and scholars and grassroots party organizations and Party members. Approved by the Central Committee of the
29、Communist Party of China, on 7 September 2015, the general office of the Central Committee of the Party issued a notice to solicit the provinces (autonomous regions, municipalities) Party, the central ministries and commissions, state ministries and commissions of the Party (party), the General Poli
30、tical Department of the military, every 3 people organization of Party of two regulations revision opinion. Central Commission for Discipline Inspection of extensive solicitation of opinions, careful study, attracting, formed a revised sent reviewers. In October 8 and October 12, Central Committee P
31、olitical Bureau Standing Committee and the Political Bureau of the Central Committee After consideration of the two regulations revised draft. On October 18, the Central Committee of the Communist Party of China formally issued two regulations. Can say, two laws amendment concentrated the wisdom of
32、the whole party, embodies the party. Second, and revision of the basic principles of two party regulations revision work and implement the partys eighteen, ten eight plenary, the spirit of the Fourth Plenary Session of the Eleventh Central Committee and General Secretary Xi Jinping important instruc
33、tions on the revised and , highlighting the ruling party characteristics, serious discipline, the discipline quite in front of the law, based on the current, a long-term, advance as a whole, with Bu Xiuding independent and . Main principle is: first, adhere to the party constitution to follow. The c
34、onstitution about discipline and self-discipline required specific, awaken the party constitution of party compasses party consciousness, maintaining the authority of the constitution. General Secretary Xi Jinping pointed out that no rules, no side round. Party constitution is the fundamental law, t
35、he party must follow the general rules. In early 2015 held the eighth session of the Central Commission for Discipline Inspection Fifth Plenary Session of the 16th Central Committee, Xi Jinping again pointed out that constitution is the party must follow the general rules, but also the general rules
36、. the revision of the and is Method in adhere to the regulations established for the purpose of combining rule of virtue is to adhere to the party constitution as a fundamental to follow, the constitution authority set up, wake up the party constitution and party rules the sense of discipline, the p
37、arty constitution about discipline and self-discipline specific requirements. 4 second is to adhere to in accordance with the regulations governing the party and the party. The Party of rule of virtue de, mainly refers to the partys ideals and beliefs, excellent traditional style. The revised the cl
38、osely linked to the self-discipline, insisting on the positive initiative, for all members, highlight the vital few, emphasized self-discipline, focusing on the morality, and the majority of Party members and the ideological and moral standards. The revised Ji method separately, Ji, Ji Yan to Method
39、, as a negative list, emphasizing the heteronomy, focusing on vertical gauge. Is this one high and one low, a positive reaction, the strict party discipline and practice results transformation for the integration of the whole party to observe moral and discipline requirements, for the majority of Pa
40、rty members and cadres provides benchmarking and ruler. Third, insist on to. In view of the problems existing in the party at the present stage, the main problems of Party members and cadres in the aspect of self-discipline and abide by the discipline to make clearly defined, especially the partys e
41、ighteen years strict political discipline and political rules, organization and discipline and to implement the central eight provisions of the spirit against the four winds and other requirements into Disciplinary provisions. Not one pace reachs the designated position, focusing on in line with rea
42、lity, pragmatic and effective. After the revision of major changes, major changes in the and modified and needs to grasp several key problems (a) adhere to according to regulations governing the party and party with morals in combination, for at the present stage, the leadership of the party members
43、 and cadres and Party members in existing main problems of self-discipline, put forward principles, requirements and specifications, showing Communists noble moral pursuit, reflected at all times and in all over the world ethics from high from low 5 common requirements. One is closely linked to the
44、self-discipline, removal and no direct relation to the provisions of . the second is adhere to a positive advocate, eight prohibition 52 are not allowed to about the content of the negative list moved into synchronization amendment . Three is for all the party members, will apply object from the lea
45、dership of the party members and cadres to expand to all Party members, fully embodies the comprehensive strictly required. The fourth is prominent key minority, seize the leadership of the party members and cadres is the key, and put forward higher requirements than the ordinary Party members. Five is to simplify, and strive to achieve concise, easy to understand, easy to remember. The revised is the ruling Party since the first insists