A Scheme for Integrating Concrete Domains into
Concept Languages
Franz Baader* and P h i l i p p H anschke*
German Research Center for AI (DFKI)
Postfach 2080
W-6750 Kaiserslautern, Germany
A b s t r a c t
A drawback which concept languages based
on K L-O N E have is that all the terminological
knowledge has to be defined on an abstract log-
ical level. In many applications, one would
like to be able to refer to concrete domains
and predicates on these domains when defin-
ing concepts. Examples for such concrete do-
mains are the integers, the real numbers, or also
non-arithmetic domains, and predicates could
be equality, inequality, or more complex pred-
icates. In the present paper we shall propose
a scheme for integrating such concrete domains
into concept languages rather than describing a
particular extension by some specific concrete
domain. We shall define a terminological and
an assertional language, and consider the im-
portant inference problems such as subsump-
tion, instantiation, and consistency. The for-
mal semantics as well as the reasoning algo-
rithms can be given on the scheme level. In con-
trast to existing KL-ONE based systems, these
algorithms are not only sound but also com-
plete. They generate subtasks which have to
be solved by a special purpose reasoner of the
concrete domain.
1 I n t r o d u c t i o n
Concept languages based on KL-ONE [Brachman and Schmolze, 1985] are used to represent the taxonomical and conceptual knowledge of a particular problem do-main on an abstract logical level. To describe this kind of knowledge, one starts with atomic concepts and roles, and defines new concepts using the operations provided by the language. Examples for atomic concepts may be H uman and Female, and for roles child. If the log-ical connective conjunction is present as language con-struct, one may describe the concept Woman as "hu-mans who are female", and represent it by the expres-sion H uman Female. Many languages provide quan-tification over role fillers which allows for example to describe the concept Mother by the expression Woman D 3child.H uman.
KL-ONE was first developed for the purpose of natural language processing [Brachman et al, 1979], and some of the existing systems are still mostly used in this context (see e.g., SB-ONE [Kobsa, 1989])- H owever, its success in this area has also led to applications in other fields (see e.g,, MESON [Edelmann and Owsnicki, 1986] which is used for computer configuration tasks, CLASSIC [Borgida et al,, 1989] which is e.g, used in the area of C A D/C A M, or K-Rep [Mays et al., 1988] which is used in a financial marketing domain),
A drawback which pure KL-ONE languages have is that all the terminological knowledge has to be defined on the abstract logical level. In many applications, one would like to be able to refer to concrete domains and predi-cates on these domains when defining concepts. An ex-ample for such a concrete domain could be the set of non-negative integers. In the above example, one might think that being human and female is not enough to make a woman. As an additional property one could require that she should be old enough, e.g., at least 21. Thus one would like to introduce a new role age, and define Woman by an expression of the form H uman Female (age)-Here stands for the unary predicate {n;n21} of all nonnegative integers greater or equal 21. Stating such properties directly with reference to a given concrete do-main seems to be easier and more natural than encod-ing them somehow into abstract concept expressions.1 Though this drawback already appears in natural lan-guage processing, it becomes even more important if one has other applications in mind. For example, in a technical application the adequate representation of geometrical concepts requires to relate points in a co-ordinate system. For that purpose one would e.g. like to have access to real arithmetic. Similar motivations have already led to extensions of KL-ONE in the above mentioned systems M E S O N, CLASSIC, and K-Rep. The MESON system provides "a separate hierarchy for de-
' Supported by the BMFT research project AKA-W1NO Supported by the BMFT research project ARC-TEC
1See e.g. [Brachman and Schmolze, 1985], Section 9.2, where so-called Structural Descriptions are used to encode the concrete predicate "less than one hour". From a compu-tational point of view, Structural Descriptions are as bad as Role Value Maps which cause undecidability of subsumption [Schmidt-SchauB, 1989].
452 Knowledge Representation
scribing non-concepts (e.g., integer ranges and strings)" ([Patel-Schneider et al., 1990), p. 8) which are given as user-defined or machine-defined predicates. Similar fea-tures are provided by the "test" construct in CLASSIC. In K-Rep "the roles of concepts may in turn be other (complex) concepts, as well as numbers, strings and .., arbitrary Lisp objects" ([Mays et al, 1988], p. 62).
For similar reasons, Logic Programming has been ex-tended to Constraint Logic Programming (CLP). The constraints in CLP languages "state properties directly in the domain of discourse as opposed to having these properties encoded into Prolog terms" ([Lassez, 1987], p.
Before describing our approach for extending a con-cept language by concrete domains we shall state some of the properties which such an extension should satisfy:
? The extension should still have a formal declarative semantics which is as close as possible to the usual semantics employed for concept languages.
? It should be possible to combine existing inference al-gorithms for concept languages with well-known rea-soning algorithms in the concrete domain in order to get the appropriate algorithms for the extension.
? One should provide a scheme for extending concept languages by various concrete domains rather than constructing a single ad hoc extension for a specific concrete domain. The formal semantics as well as the combination of the algorithms should already be treated on this scheme level.
In order to satisfy these properties it is important to choose an appropriate interface between the concept lan-guage and the concrete domain. The interface which we shall use in the present paper was inspired by a construct which is e.g. present in the CLASSIC sys-tem, namely coreference constraints (also called agree-ments) between chains of single-valued roles (also called features).2W i t h such a coreference constraint one can for example express the concept of all women whose fa-ther and husband are of the same age by the expression Woman 1~1 (father age) [ (husband age). But one cannot express that the husband is even older than the father. This becomes possible if we take the set of nonnega-tive integers as concrete domain. Then we can sim-ply write Woman (husband age, father age) where > stands for the binary predicate {(n,m);n m} on non-negative integers. More general, our extension will al-low to state that feature chains satisfy a (nonnecessarily binary) predicate which is provided by the concrete do-main in question.
The next section will contain a formal definition of what we mean by the notion "concrete domain". Section 3 describes our scheme for extending a concept language by an arbitrary concrete domain. As a starting point for this extension we use the language ACC of [Schmidt-Schaufi and Smolka, 199l]. The reason for choosing this language was that it is large enough to exhibit most of 2Agreements on feature chains are just the restriction of Role Value Maps to single-valued (i,e., functional) roles; but unlike Role Value Maps they usually do not cause undecid-ability of subsumption [H ollunder and Nutt, 1990]. the problems connected with such an extension. Taking
a larger language (e.g., including number restrictions) would only mean more work without bringing new in-sights. Section 4 describes how an assertional component
for such an extended concept language can be defined.
For both the terminological and the assertional part of
our formalism we shall introduce the important infer-
ence problems. Because of the space limitations it is not possible to present the algorithm which can be used to decide all of these problems. A complete presentation
of the algorithm, and a proof of its correctness can be found in [Baader and H anschke, 1991], It is important
to note that this algorithm is not only sound but also complete.3
2 Concrete Domains
The following definition formalizes the notion "concrete domain" which has until now only been used in an intu-
itive sense,
? The runcrete domain Z is defined as R with the only difference that dom(Z) is the set of all integers instead
of all real numbers.
? Our next example leaves the realm of numbers and arithmetic. Assume that D B is an arbitrary rela-
tional database equipped with an appropriate query
3A l l the above mentioned systems employ sound but in-complete algorithms.
^For the sake of simplicity we assume here that the for-
mula itself is the predicate name.
Baader and Hanschke 453
454 Knowledge Representation
The philosophy underlying this definition is that we assume that the concrete domain 7) is sufficiently struc-tured by the predicates in pred(D). T h a t means that we do not want to define new classes of elements of dorn(V) or new relations between elements of dom(D) with the help of our concept language. Consequently, concept terms are always interpreted as subsets of the abstract domain, i.e., an individual of the concrete domain cannot
be element of a concept.
In our example, it is very easy to see that Woman subsumes Mother. owever, in general it is not at all trivial to determine such relationships, Until recently, sound and complete subsumption algorithms were only known for rather trivial concept languages (see [Levesque and Brachman, 1987]). Consequently, all the existing KL-ONE systems use only sound, but incomplete algo-rithms. If such an algorithm gives a positive answer, a subsumption relationship really exists; but if its answer is negative, then we do not know anything. A subsump-tion relationship may or may not exist. In [Schmidt-SchauB and Smolka, 1991] a sound and complete sub-sumption algorithm for ACC is described. The underly-ing method of constraint propagation was used in [H ol-lander e t al,, 1990] to derive algorithms for various other concept languages. This method can—with appropri-ate modifications—also be applied to the languages of the form ACC(D). As a subtask, such an algorithm for ACC(V) will have to decide satisfiability of conjunctions of the form A i =i Pi(x (i )
) in the concrete domain. Thus we shall have to require that V is admissible.
In [Baadcr and H anschke, 1991] we do not directly give a subsumption algorithm for ACC(V), Instead we reduce the subsumption problem to a problem which will be introduced in the next section: the consistency problem for A-boxes.
4 The Assertional Language
The terminological formalism introduced in the previ-ous section allows to describe knowledge about classes of objects (the concepts) and relationships between these classes (e.g., subsumption relationships which are conse-quences of the descriptions). Many applications, how-ever, require that one can also say something about ob-jects in the world. For this reason, most KL-ONE sys-tems provide additional assertional capabilities. This assertional part of the system uses the concept terms for making statements about parts of a given world. The ex-pressiveness of this component varies between the rather weak formalism employed in the original K L -O N E sys-tem [Brachman and Schmolze, 1985] to full first order predicate logic as used in KRYPTON [Brachman et al., 1985], We shall now show how to integrate a concrete domain into an assertional language which is similar to the ones used in K A N D O R [Patel-Schneider, 1984], ME-SON [Edelmann and Owsnicki, 1986], CLASSIC [Borgida et al., 1989], or BACK [Nebel and von Luck, 1988]. 4.1 S y n t a x a n d S e m a n t i c s
Let V be an arbitrary concrete domain, We have seen in Section 3 that we have to deal with two different kinds of objects: the individuals of the concrete domain and the individuals in the abstract domain (see Definition 3.2). The names for objects of the concrete domain will come from a set OC of object names, and the names for objects of the abstract domain from a set OA.
D e f i n i t i o n 4.1 Let OC and OA be two disjoint sets of object names. The set of all assertional axioms is defined as follows. Let C be a concept term of ACC(V), R be a role name, f be a feature name, P be an n-ary predicate name of D, and let a, 6 be elements of OA and y, y 1, ..., y n be elements of OC. Then the following are assertional axioms:
Baader and Hanschke 455
456 Knowledge Representation
Finally, the subsumption problem can also be reduced to the instantiation problem, and thus to the consistency problem for A~boxes, In fact, C is subsumed by D with respect to T iff the abstract object a is an instance of D with respect to the A-box {o ; C} together with T.
In [Baader and H anschke, 1991] a sound and com-plete algorithm is described which decides the consis-tency problem for ALC(V), provided that the concrete domain V is admissible. Such an algorithm for ACC without concrete domain and features can be found in [Hollunder, 1990]. Since the other inference problems in-troduced above can be reduced to the consistency prob-lem, we thus have
T h e o r e m 4.3 Let V be an admissible concrete domain. Then there exists a sound and complete algorithm which is able to decide the following problems for ACC(V): the subsumption problem w.r.t. a T-box, the instantiation problem w.r.t. an A-box together with a T-box, and the consistency problem for an A-box together with a T-box.
5 Conclusion
We have proposed a KL-ONE based knowledge represen-tation and reasoning system which is hybrid in two re-spects. On the one hand, it makes the usual distinction between two epistemological different kinds of knowl-edge, the terminological knowledge and the assertional knowledge. On the other hand, the terminological and assertional language, which usually describes the knowl-edge on an abstract logical level, is extended by allowing to refer to concrete domains and predicates on these do-mains.
The different parts of the system are integrated with the help of a unified model-theoretic semantics. Reason-ing in the terminological and the assertional part can be done with the help of a single basic reasoning algorithm. This algorithm creates subtasks which have to be solved by the special purpose reasoner of the concrete domain. But there is no other interaction necessary between our basic reasoning algorithm and the reasoner on the con-crete domain.
Our approach differs from other extensions of KL-ONE which were done for similar reasons in several respects. Firstly, we have proposed a scheme for such an extension, and not a particular extension by some specific concrete domains. The formal semantics and the algorithm are given on this scheme level. Secondly, the basic reason-ing algorithm is not only sound but also complete with respect to this semantics. In addition, we can utilize spe-cial purpose reasoners which may already exist for the concrete domain in question- This shows another differ-ence to e.g. the MESON system where the important re-lationships between the user-defined or machine-defined predicates have to be explicitely supplied by the user.
An advantage other systems have compared to our approach is that their incomplete algorithms are usu-ally polynomial, whereas our complete algorithm is of complexity at least PSPACE (depending on the concrete domain). H owever, one should keep in mind that these complexity results are worst case results. The algorithm
may behave much better for "typical" knowledge bases.
Our main motivation for developing the presented K L -oNE extension was to represent knowledge in a mechan-ical engineering domain. In particular, we wanted to describe both geometric and other attributes of lathe work pieces in a unified framework. For that purpose we intend to use the language ACC(R) where geometric properties can be described with the help of predicates over real numbers. Currently, we are experimenting with
a prototypical implementation which uses a relatively small fragment of real arithmetics as its concrete do-main.
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(一) 假定你是红星中学初三学生李华。你的美国朋友Jim在给你的邮件中提到他对中国新近出现的一种共享单车“mobike”很感兴趣，并请你做个简要介绍。请你给Jim回信，内容包括： 1. 这种单车的使用方法(如：APP查看车辆、扫码开锁等); 2. 这种单车的优势; 3. 你对这种单车的看法。 注意：1. 词数不少于80; 2. 开头和结尾已给出，不计入总词数。 提示词：智能手机smartphone, 二维码the QR code 参考范文 Dear Jim, I’m writing to tell you more about the new form of sharing bike mobike mentioned in your latest letter. It’s very convenient to use if you have a smartphone. What you do is find a nearest mobikethrough the APP, scan the QR code on the bike, and enjoy your trip. Compared to other forms of sharing bike, the greatest advantage of mobike is that you can easily find one and never worry about where to park it. It is becoming a new trend as a means of transportation, which relieves the traffic pressure and does good to the environment as well. Hope to ride a mobike with you in China. Yours, Li Hua (二) 最近很多大城市都投放了共享单车(shared bikes)，比如摩拜单车(Mobike)、Ofo共享单车等。由于它们方便停放，骑车也能起到锻炼身体的作用，作为代步工具很受大家欢迎。但是，各地也出现了很多毁车现象，比如刮掉车上的二维码(QR code)、上私锁等。 你对这种现象怎么看?你对共享单车公司有什么建议吗?写一篇符合逻辑的英语短文，80词左右。 参考词汇：bike-sharing companies 共享单车公司，Mobike 和Ofo 是两家共享单车公司，convenience 方便，register登记 参考范文 The shared bikes like Mobike and Ofo bring great convenience to people. You needn’t lock them by simply using your smart phone. They can take you where the subway and bus don’t go. And they can be left anywhere in public for the next user. However, bad things happen. Some people damage the QR code on the bike, or use their own lock, which causes trouble to other users. In my opinion, it’s difficult to turn these people’s ideas in a short time. Therefore, bike-sharing companies like Mobike and Ofo need to do something. For example, those who damage the bike should pay for their actions. Also, because people use their real name toregister as a user, it’s a good way to connect to one’s personal credit. In the end, what I want to say is to take good care of public services. (三) 共享单车(bicycle sharing)已成为时下最热的话题之一，请你就这一话题写一篇短文。内容须包括三方面：1. 共享单车蓬勃发展，成为社会热潮;2. 共享单车带来便利，但也存在问题;3. 我对解决问题的建议。 参考范文 Bicycle Sharing With the development of technology, bicycle sharing comes into people's lives. It becomes more and more popular and much news reported it. At the same time, we should see that there are some problems caused by bicycle sharing. On one side, bicycle sharing makes it very convenient of people traveling. You can find a bicycle anywhere at any time when you want to go out for a cycling, and the price of one trip is very low. It can save time for people. On the other side, its management is not perfect. Even kids can open the lock and ride the bicycle, there is no doubt that such behavior is very dangerous.
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AN EXCITING JOB I have the greatest job in the world. I travel to unusual places and work alongside people from all over the world. Sometimes working outdoors, sometimes in an office, sometimes using scientific equipment and sometimes meeting local people and tourists, I am never bored. Although my job is occasionally dangerous, I don't mind because danger excites me and makes me feel alive. However, the most important thing about my job is that I help protect ordinary people from one of the most powerful forces on earth - the volcano. I was appointed as a volcanologist working for the Hawaiian V olcano Observatory (HVO) twenty years ago. My job is collecting information for a database about Mount Kilauea, which is one of the most active volcanoes in Hawaii. Having collected and evaluated the information, I help other scientists to predict where lava from the volcano will flow next and how fast. Our work has saved many lives because people in the path of the lava can be warned to leave their houses. Unfortunately, we cannot move their homes out of the way, and many houses have been covered with lava or burned to the ground. When boiling rock erupts from a volcano and crashes back to earth, it causes less damage than you might imagine. This is because no one lives near the top of Mount Kilauea, where the rocks fall. The lava that flows slowly like a wave down the mountain causes far more damage because it
钢筋施工技术标准及工艺流程 本施工技术标准及工艺流程将参照相关国家规范、国家标准及建筑行业 标准制定，钢筋施工人员需依据建设施工设计图纸和施工方案等编制钢筋用 料单，并经项目技术负责人审核认可签字后开始施工。 钢筋施工标准及流程如下: 一、钢筋放样 根据施工图纸编制的钢筋用料单中应包含钢筋的规格、形状、长度、数量、应用部位等信息。根据结构施工图下料，做到长短料相配合，杜绝浪费。 二、钢筋进场 钢筋进场后需缓送轻放，分型号堆放整齐，下部距地面20公分，上部 覆盖薄膜，防止雨淋生锈。 三、钢筋加工 加工前应准备好的机械设备包括钢筋冷拉机、调值机、切断机、弯曲成型机、弯箍机、点焊机、对焊机、电弧焊机及相应吊装设备。各种设备在操作前检修完好，保证正常运转，并符合安全规定。 钢筋的加工制作应在专门的操作区域内进行，严禁在规定区域外加工操作。操作步骤如下： （1）除锈：钢筋加工前将钢筋表面的油渍、漆渍及浮皮、铁锈等清除干净，可结合冷拉工艺除锈，使其与混凝土的粘接效果达到最佳。 （2）调直：调直后应保证钢筋平直，经调直后的钢筋不得有局部弯曲、死弯、小波浪形，其表面伤痕不应使钢筋截面减少5%，无局部曲折。 （3）切断：钢筋的切断需遵循“先长后短，长短搭配，统筹排料”的原则，尽量减少和缩短钢筋短头，以节约钢材，避免浪费。 （4）弯曲成型：手工弯曲和机械弯曲相结合进行，钢筋弯曲后，弯曲内皮收缩、外皮延伸、轴线长度不变，弯曲点处不得有裂痕。 根据施工计划和现场实际情况将加工成型的钢筋成品按分批、分期码放整齐，挂牌标识，露天存放时应对钢筋成品采取保护措施，防止变形和生锈。
四、钢筋的安装绑扎 成品钢筋在吊装运送过程中应遵循就近原则，缓吊轻放，一次到位，避免对成品钢筋件造成毁坏变形。绑扎顺序由下至上、层次鲜明，合理规划。 （一）、基础钢筋绑扎 工艺流程：清理垫层→基础钢筋绑扎→画线或弹线→绑扎底板下层受力钢筋绑扎→预留、预埋→板的支座马凳铁通长设置→后浇带处止水带的安装→板的上层钢筋绑扎→复检 操作工艺： （1）绑扎前应沿轴线方向在垫层上画好等分线； （2）网格绑扎时交叉点需绑扎牢固，扎丝扣成八字形，防止网片歪曲变形； （3）钢筋搭接长度要符合国家规范和设计要求； （4）筏板基础长向钢筋用直螺纹连接，短向钢筋用闪光对焊连接； （二）、柱钢筋安装绑扎 工艺流程：清理基层杂物→安放和绑扎柱竖向受力筋→套柱箍筋→画箍筋间距线→绑扎箍筋→复检 操作工艺： （1）清理柱基处杂物，以便看清基轴线，安放柱子竖向钢筋和定位箍筋应焊接牢固，防止浇筑混凝土时发生位移； （2）按图纸设计间距套放箍筋，由上而下采用缠扣绑扎牢固，不得跳扣绑扎； （3）柱竖向钢筋采用机械或焊接连接时，其搭接长度和连接要求应复合设计规范要求； （4）箍筋的弯钩叠合处应沿拄子竖筋交错布置，并绑扎牢固； （5）柱筋保护层厚度应符合规范要求，如主筋外皮为25mm； （三）、梁钢筋安装绑扎 工艺流程：清理梁基底杂物→画主次梁箍筋间距→放主梁次梁箍筋→穿主梁底层纵筋及弯起筋→穿次梁底层纵筋并与箍筋固定→穿主梁上层纵向架立筋→按箍筋间距绑扎→穿次梁上层纵向钢筋→按箍筋间距绑扎→复检
[标签:标题] 篇一：关于汽车的英语作文 好的 Nowadays, with the rapid improvement of people’s living standards, cars have become an indispensable part of people's lives,so that more and more people have a car of their own, especially in cities. It brings some benefits for us but also causes many problems at the same time. For one thing,there’s no doubt that cars provide much convenience for people to go where they want to quickly and easily. Especially on weekday,driving a car can save a lot of time for us to go to work.When some places are too far away from our home, driving our own car is also convenient, we can go wherever we want. However,for another, too many cars will lead to the pressure of public transport, a series of problems will appear.First of all,it will bring about more air pollution,a large amount of polluted air given off by cars do great harm to our health.What’s more, as the existing roads are not so wide for the increasing number of cars,undoubtedly,traffic jams will become more and more serious. Last but not least, cars also place burden on the public facilities in providing more parking lots. As far as I am concerned,everything has its advantages and disadvantages. It’s high time that effective action must be token to limit the ever growing number of cars, the government should take measures to control the air pollution from the cars. Some roads should be widened and more new roads should be constructed. Only in this way，will people benefit from the popularity of cars. 坏的 Nowadays, with the rapid improvement of people's living standards, cars have become an indispensable part of people's lives,so that more and more people have a car of their own, especially in cities.It brings some benefit for us but also causes many problems at the same time. For one thing,it's no doubt that that cars provide much convenience for people to go where they want to quickly and easily. Especially on weekday,driving a car can save a lot of time for us to go to work.When some places are too far away from our home, driving our own car is also convenient, we can go wherever we want. However,for another, too many cars will lead to the pressure of public transport, a series of problems will appear.First of all,it will bring about more air pollution,a large amount of polluted air given off by cars do great harm to our health .What's more, as the existing roads are not so wide for the increasing number of cars,undoubtedly,traffic jams will become more and more serious. Last but not least, cars also place burden on the public facilities in providing more parking lots. As far as I am concerned,everything has its advantages and disadvantages. It's high time that effective action must be token to limit the ever growing number of cars, the government should take measures to control the air pollution from the cars. Some roads should be widened and more new roads should be constructed. Only in this way,will people benefit from the popularity of cars. 篇二：雅思作文高分范文：私家车的利与弊 智课网IELTS备考资料 雅思作文高分范文：私家车的利与弊
基础钢筋绑扎施工工艺标准 10.1总则 10.1.1适用范围 适用于建筑结构工程的基础及底板钢筋绑扎。 10.1.2编制参考标准及规范 《混凝土结构设计规范》( GB50010—) ; 《混凝土结构工程施工质量验收规范》( GB50204—) ; 《钢筋焊接及验收规程》( JGJ18—96) ; 《建筑施工安全检查标准》( JGJ59—99) ; 《中国建筑工程总公司施工安全检查生产监督管理条例》; 钢筋、绑丝等相关材料标准和有关规定。 10.2术语、符号 10.2.1现浇结构 系现浇混凝土结构的简称, 是以现场支模并整体浇筑而成的混凝土结构。 10.2.2HPB235级钢筋 系指现行国家标准《钢筋混凝土用热轧光圆钢筋》( GB13013—1991) 中的Q235钢筋, 相当于原级别I级钢筋。 10.2.3HRB335( 20MnSi) 钢筋 系指现行国家标准《钢筋混凝土用热轧带肋钢筋》( GB1499—1998) 中的HRB335钢筋, 相当于原级别II级钢筋。 10.2.4HRB400( 20MnSiV、20MnSiNbv、20MnSiTi) 级钢筋
系指现行国家标准《钢筋混凝土用热轧带肋钢筋》( GB1499—1998) 中的HRB400钢筋, 相当于原级别III级钢筋。 10.2.5RRB400( K20MnSi) 级钢筋 系指现行国家标准《钢筋混凝土用余热处理钢筋》( GB13014—91) 中的KL400钢筋, 相当于原级别III级钢筋。 10.2.6La 钢筋锚固长度。 10.3基本规定 10.3.1一般规定 ( 1) 当钢筋的品种、级别或规格需作变更时, 庆办理材料代用手续。 ( 2) 浇筑混凝土前, 应进行钢筋隐蔽工程验收, 其内容包括: 1) 纵向受力钢筋的规格、数量、位置等; 2) 钢筋的连接方式、接头位置、接头数量、接头面积百分率等; 3) 箍筋、横向钢筋的品种、规格、数量、间距等; 4) 预埋件的规格、数量、位置等; 5) 避雷网线的布设与焊接等。 10.3.2质量目标 达到《混凝土结构工程施工质量验收规范》( GB50204—) 的要求, 并符合图纸及”施工组织设计”的要求。 10.4施工准备 10.4.1技术准备
介绍北京的英语作文1篇 篇一MyFamily Ilovemyfamily,becauseIhaveahappyfamily. MyfatherisanEnglishteacher.HisnameisJacky.Heisthirty-eight.Helikesplay ingbasketball.What’smymotherjop?Issheateacher?Yes,you’reright!Mymotherisverykindandnice,sheisthirty-seven.Mymotherisalways laboriouswork.Ilovemyparents! OnStaurdayandSunday,Ioftengotothelibraryandplaythepiano,Myfathergot oplaybasketball.Sometimes,wewatchTVandlistentomusicathome. Ilovemyfamily.BecauseI’mveryhappytolivewithmyparentstogether! 篇二MyFamily MyFamily Everyonehasafamily.Weliveinitandfeelverywarm.Therearethreepersonsin myfamily,mymother,fatherandI.Welivetogetherveryhappilyandtherearema nyinterestingstoriesaboutmyfamily. Myfatherisahard-workingman.Heworksasadoctor.Healwaystrieshisbesttoh elpevery,patientandmakepatientscomfortable.Butsonetimesheworkssohard thathecan”trememberthedate.
1承台钢筋绑扎施工工艺 1.1执行标准 《混凝土结构工程施工质量验收规范》（GB50204—2002）（2010版）； 《混凝土结构设计规范》（GB50010—2010）； 《钢筋焊接及验收规程》（JGJ18—2012）； 《冷轧带肋钢筋混凝土结构技术规程》(JGJ95—2011)； 《中国建筑工程总公司建筑工程施工工艺标准》； 钢筋、绑扎丝等相关材料标准和有关规定。 1.2施工工艺流程和操作要点 1.2.1施工工艺流程 1.2.2操作要点
确定承台十字轴线，并用墨线弹在施工垫层地板上。经驻地
监理工程师核查、批准后绑扎。 2）划钢筋位置线：按图纸标明的钢筋间距，算出底板实际需用的钢筋根数，一般让靠近底板模板边的那根钢筋离模板边为5cm，在底板上弹出钢筋位置线。 2、钢筋加工： 1）钢筋清理：钢筋表面应洁净，粘着的油污、泥土、浮锈使用前必须清理干净。 2）钢筋调直：可用机械或人工调直。经调直后的钢筋不得有弯曲、死弯、小波浪形，其表面伤痕不应使钢筋截面减小5﹪. 3）钢筋截断：应根据钢筋直径、长度和数量，长短配搭，先断长料后端短料，尽量减少和缩短钢筋短头，以节约钢材。 3、钢筋运输： 将加工好的钢筋运往施工现场时，应做好钢筋编号，并做好钢筋的运输管理，防止钢筋在运输过程中发生变形，被污染。 4、底板钢筋绑扎： 1）按弹出的钢筋位置线，先铺下层钢筋。根据底板受力情况，决定下层钢筋哪个方向钢筋在下面，一般情况下先铺短向钢筋，再铺长向钢筋。 2）钢筋绑扎时，靠近外围两行的相交点每点都绑扎，
中间部分的相交点可相隔交错绑扎，双向受力的钢筋必须将钢筋交叉点全部绑扎。 3）摆放底板混凝土保护层用砂浆垫块，垫块厚度等于保护层厚度，按每1m左右距离梅花型摆放。如底板较厚或用钢筋较大，摆放距离可缩小。 5、钢筋固定： 1）先绑2～4根竖筋，并画好横筋分档标志。然后在下部及齐胸处绑两根横肋定位，并画好竖筋分档标志。一般情况横筋在外。竖筋在里，所以先绑竖筋后绑横筋。横竖筋的间距及位置应符合设计要求。 2）在钢筋外侧应绑上带有铁丝的砂浆垫块，以保证保护层的厚度。 6、顶板钢筋绑扎： 在进行顶板钢筋绑扎前应该现对该基础再次施工放样，即对已经的施工完成的钢筋绑扎进行检查，能确定基础的平面尺寸。根据放样进行顶板的钢筋绑扎。绑扎的工艺与底板的施工工艺基本一致。 7、预埋件钢筋绑扎： 1）根据弹好的肋板（立柱）位置线，将肋板（立柱）伸入基础的插筋绑扎牢固，插入基础深度要符合设计要求，甩出长度不宜过长，其上端应采取措施保证甩筋垂直，不歪斜、倾倒、变位。
汽车的重要性《英语作文》 The automobile has become one of the most important means/ways of transportation in the world since it was invented. The automobile has completely changed the lifestyles of almost all the people in the world. In the past, animals like horses and camels were used for traveling and transporting goods. Automobiles are more comfortable and faster. Automobiles have also made it possible for us to transport large quantities of goods and people at the same time. Besides, the invention of the automobile has provided jobs for millions of people all over the world. 翻译： 汽车已经成为世界上最重要的交通工具之一，因为它是发明的。汽车已经完全改变了世界上几乎所有的人的生活方式。 在过去，像马和骆驼的动物被用来运送货物。汽车更舒适，更快速。汽车也使我们能够在同一时间运送大量货物和人。 此外，汽车的发明为全世界上百万的人提供了工作。
三一文库（https://www.doczj.com/doc/c09659198.html,） 〔我想去北京英语作文〕 我想去北京的英语作文如何写？那么，下面是小编给大家整理收集的我想去北京英语作文，供大家阅读参考。 我想去北京英语作文1 I’d like to go to a beautiful place. I think it would be Beijing. Beijing is not only our capital city, but also a famous city with long history and wonderful culture. Beijing is also China’s political and cultural center. There’re many old places of great interest, such as the Great Wall, the Summer Palace, the Forbidden City, the Temple of Heaven, and Tiananmen Square. Once you see Tiananmen Square, you will think of Beijing. It has been the symbol of Beijing since 1949. 我想去北京英语作文2 I went to Beijing more than eight times. Beijing is the capital of China. It’s a big city. I am very familiar with Beijing. It takes an hour and forty minutes from Nantong to Beijing by plane. There are many tall buildings in Beijing. It’s a modern city. My family visited the Great Wall, the Summer
房屋建筑工程钢筋绑扎施工方法 一、基础钢筋绑扎施工方法和施工措施 1工艺流程： 划钢筋位置线→运钢筋到使用部位→绑底板及梁钢筋→绑墙钢筋 2划钢筋位置线：按图纸标明的钢筋间距，算出底板实际需用的钢筋根数，一般让靠近底板模板边的那根钢筋离模板边为5cm，在底板上弹出钢筋位置线（包括基础梁钢筋位置线）。 3绑基础及基础梁钢筋 3.l按弹出的钢筋位置线，先铺底板下层钢筋。根据底板受力情况，决定下层钢筋哪个方向钢筋在下面，一般情况下先铺短向钢筋，再铺长向钢筋。 3.2钢筋绑扎时，靠近外围两行的相交点每点都绑扎，中间部分的相交点可相隔交错绑扎，双向受力的钢筋必须将钢筋交叉点全部绑扎。如采用一面顺扣应交错变换方向，也可采用八字扣，但必须保证钢筋不位移。 3.3摆放混凝土保护层用砂浆垫块，垫块厚度等于保护层厚度，按每1m左右距离梅花型摆放。如基础底板较厚或基础梁及底板用钢量较大，摆放距离可缩小，甚至砂浆垫块可改用铁块代替。 3.4底板如有基础梁，可分段绑扎成型，然后安装就位，或根据梁位置线就地绑扎成型。 3.5基础底板采用双层钢筋时，绑完下层钢筋后，摆放钢筋马凳或钢筋支架（间距以1m左右一个为宜），在马凳上摆放纵横两个方向定位钢筋，钢筋上下次序及绑扣方法同底板下层钢筋。 3.6钢筋如有绑扎接头时，钢筋搭接长度及搭接位置应符合施工规范要求，钢筋搭接处应用铁丝在中心及两端扎牢。如采用焊接接头，除应按焊接规程规定抽取试样外，接头位置也应符合施工规范的规定。 3.7由于基础底板及基础梁受力的特殊性，上下层钢筋断筋位置应符合设计
要求。 3.8根据弹好的柱位置线，将柱伸入基础的插筋绑扎牢固，插入基础深度要符合设计要求，甩出长度不宜过长，其上端应采取措施保证甩筋垂直，不歪斜、倾倒、变位。 二、构造柱、圈梁钢筋绑扎施工方法和施工措施 1构造柱钢筋绑扎： 1.1工艺流程：预制构造柱钢筋骨架→修整底层伸出的构造柱塔接筋→安装 构造柱钢筋骨架→绑扎搭接部位箍筋 1.2预制构造柱钢筋骨架： 1.2.1先将两根竖向受力钢筋平放在绑扎架上，并在钢筋上画出箍筋间距。 1.2.2根据画线位置，将箍筋套在受力筋上逐个绑扎，要预留出搭接部位的长度。为防止骨架变形，宜采用反十字扣或套扣绑扎。箍筋应与受力钢筋保持垂直；箍筋弯钩叠合处，应沿受力钢筋方向错开放置。 1.2.3穿另外二根受力钢筋，并与箍筋绑扎牢固，箍筋端头平直长度不小于10d（d为箍筋直径），弯钩角度不小于135°。 1.2.4在柱顶、柱脚与圈梁钢筋交接的部位，应按设计要求加密柱的箍筋，加密范围一般在圈梁上、下均不应小于六分之一层高或45cm，箍筋间距不宜大于10cm（柱脚加密区箍筋待柱骨架立起搭接后再绑扎）。 1.3修整底层伸出的构造柱搭接筋：根据已放好的构造柱位置线，检查搭接筋位置及搭接长度是否符合设计和规范的要求。底层构造柱竖筋与基础圈梁锚固；无基础圈梁时，埋设在柱根部混凝土座内， 1.4安装构造柱钢筋骨架：先在搭接处钢筋上套上箍筋，然后再将预制构造柱钢筋骨架立起来，对正伸出的搭接筋，搭接倍数不低于35d，对好标高线，在竖筋搭接部位各绑3个扣。骨架调整后，可绑根部加密区箍筋。 1.5绑扎搭接部位钢筋：
汽车英文演讲稿 篇一：汽车英语演讲稿 Good morning everyone ,today, the topic of my lecture（演讲） is “Do you love automobiles（'tmbilz）”. before I start my speech ,I want to ask a question,did there anybody present had seen the movie”the Fast and the Furious['fjrs]”.There are many cars of different styles in the movie,for example ,when you see the movie,you can find roadsters（跑车） just like Porsche（保时捷） GT3,sports utility (通用的）vehicles （车）SUV such as Volkswagen ['f:lks,va:gn]Touareg ['twɑ:reɡ](大众途锐）,even armored cars ,all of them are so powerful and beautiful. When I was a child,I dreamed I can have a car like FORD GT 40,this racing bike（跑车） is amazing and fantastic,but as time goes on ,my hobby is changing,now my favorite car is Jeep Rubicon,this is a car I really want ,it’s dynamic performance（性能） and off-road （越野） performance is top-ranking（一流的） ,which other ordinary SUV is unable to compare; the shape and color of this car is magnificent (华丽的） [mg'nfs()nt],and it’s gear-shift system（齿轮转
小学一年级介绍北京的英语作文 Beijing is an ancient city with a long history. Back in 3000 years ago in Zhou dynasty, Beijing, which was called Ji at the moment, had been named capital of Yan. Thereafter, Liao, Jin, Yuan, Ming and Qing dynasty all made Beijing their capital. Therefore, Beijing was famous for "Capital of a thousand years". The long history leaves Beijing precious cultural treasure. Winding for several kilometers in Beijing area, the Great Wall is the only man-made structure that could been seen in the space. The Summer Palace is a classic composition of ancient royal gardens, and the Forbidden City is the largest royal palaces in the world. Tiantan is where the emperor used to fete their ancestors, and also the soul of Chinese ancient constructions. The four sites above has been confirmed world cultural heritage by UNESCO. However, the best representatives for Beijing are the vanishing Hutongs and square courtyards. Through hundreds of years, they have become symbol of Beijing's life. Tian'anmen square being still brilliant today with cloverleaf junctions and skyscrapers everywhere, the old-timey scene and modern culture are combined to present a brand new visage of Beijing. As Beijing has been confirmed home city of Olympics 2008, the spirit of "green Olympics, scientific Olympics and humanized Olympic" will surely bring more and more changes to Beijing, promote the development of sports and Olympics in China as well as in the world, and strengthen the friendly communications between Chinese and foreign people. 北京是一个有着悠久历史的古城。 早在 3000 年前的周朝,北京,这叫霁,被命 名为首都燕。此后,辽、金、元、明、清都是北京首都。因此,北京著名的一千年 的“资本”。 悠久的历史使北京宝贵的文化瑰宝。绕组在北京地区几公里,长城是唯一的 人造结构,可以在空间。 颐和园是古代皇家园林的经典组合,和故宫是世界上最大 的皇家宫殿。 天坛是皇帝用来祭祀他们的祖先的地方,也是中国古代建筑的灵魂。 上面的四个网站已经确认被联合国教科文组织世界文化遗产。然而,北京最好的 代表是消失的胡同和广场庭院。数百年来,他们已经成为北京的生活的象征。天 安门广场到处都在今天依然灿烂的蝶式路口和摩天大楼的,古色古香的场景和现 代文化相结合,提出一个全新的北京的面貌。 随着北京 2008 年奥运会已被证实的家乡,精神的“绿色奥运、科技奥
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西蒋峪房地产开发项目一标段 9#楼钢筋施工方案 编制: 审核: 审批: 建筑单位: 济南城市建设投资集团有限公司 监理单位: 济南市建设监理有限公司 施工单位: 中国建筑第八工程局有限公司 二〇一五年五月四日
目录 一工程概况 (1) 二编制依据 (1) 三施工准备 (1) 3.1 技术准备 (1) 3.2 机具准备 (3) 3.3 材料准备 (3) 四主要施工方法 (3) 4.1 工艺流程 (4) 4.2 钢筋堆放 (5) 4.3 钢筋加工 (5) 4.4 钢筋连接 (6) 4.5 钢筋绑扎 (8) 五质量要求 (16) 6.1 钢筋绑扎及预埋件的允许偏差 (16) 6.2 钢筋加工的允许偏差 (17) 6.3 质量控制要点 (17) 六安全文明措施 (17) 七成品保护措施 (18)
一工程概况 西蒋峪B地块房地产开发项目9#楼，拟建场地位于济南市历下区龙鼎大道以西，原西蒋峪村内，东临孟家水库，南临济南西蒋峪公租房项目，北距奥体中心约2.7公里。9#楼位于市政道路北侧，与3#车库相连（与车库位置见下图），地下3层，地上20层，东西长59.19m，南北长18.5m，总高度约69.9m。 本工程为剪力墙结构，剪力墙抗震等级为三级，基础为条形+筏板基础，基础高度1000mm，基础底标高-10.920m。 二编制依据 西蒋峪房地产开发项目一标段建筑、结构设计图纸 《地基与基础工程质量验收规范》GB50202-2002 《混凝土结构工程施工质量验收规范》GB50204-2002 《钢筋机械连接通用技术规程》JGJ107-2010 《钢筋混凝土用热轧带肋钢筋验收标准》GB1499.1-2007 《钢筋混凝土用热轧带肋钢筋验收标准》GB1499.2-2008 《建筑机械使用安全技术规程》JGJ33-2001 《施工现场临时用电安全技术规范》JGJ46-2005 《混凝土结构施工图平面整体表示方法制图规则和构造详图》11G101-1 《混凝土结构施工图平面整体表示方法制图规则和构造详图》11G101-2 《混凝土结构施工图平面整体表示方法制图规则和构造详图》11G101-3 三施工准备 3.1 技术准备 1、由项目技术负责人组织有关人员学习施工规范和工艺标准，熟悉施工图纸，并结合实际讨