(人教新课标)一年级数学上册教案 8、7、6加几 2
8、7、6加几
教学目标：
1. 通过对问题情境的探索，使学生在已有的经验的基础上，自主探索计算8、7、6加几的各种方法。
2. 使学生进一步理解“凑十法”，并能正确熟练地口算8、7、6加几。
3. 培养学生初步的观察、比较、抽象及概括能力、动手操作能力和对知识的迁移、类推能力。
4. 培养学生合作、探索的意识及环保意识，对学生进行热爱大自然的思想教育。
5. 使学生感受到生活中处处有数学。
教学重点：
理解“凑十法”的思维过程。
教学难点：
自主探索计算8、7、6加几的各种方法。
教学过程：
一、复习旧知，新知铺垫
1. 口算。
2. 括号里能填几。
3. 分解数的组成。
（通过“数的组成”这部分复习，为下面的学习进行必要的铺垫）
二、新课
（一）创设情境，激发求知的欲望
课件出示风景片及情境图。
教师创设情境：这里山清水秀，绿树成荫，小桥流水，到处是盛开的鲜花，无论走到哪里都生机盎然，充满着绿色的气息，在这里还生活着一群可爱的小动物，你喜欢这儿吗？现在就让我们出发，去公园好吗？可是你们要注意在公园游览时，要爱护那里的一草一木，保护优美的环境，不要破坏它，要和那里的小动物做朋友，不要伤害他们好吗？同学们，前面就是公园了，我们要知道一共有多少小朋友才能买门票进公园，你知道一共来了多少个小朋友吗？
（二）自主探索
1. 探索一共有多少小朋友。
指名说，你是怎么知道的？
2. 小组合作讨论
师巡视，注意发现不同的方法。
3. 小组汇报交流
生可能出现的三种算法：
（1）数数法：1、2、3……12、13，一共有13个人。
（2）接数法：左边有5个人，然后接着数6、7、8……13，一共有13个人。
（3）凑十法：左边有8个人，把右面的2个人与这8个人合起来，凑成10人，再加上剩下的3个人，一共是13个人。
4. 教师小结：这几种方法都不错，那你最喜欢用哪一种方法？
（三）动手操作，自我感悟，探求新知
1. 探索用计算方法怎样求一共有多少个小朋友，应该怎样列算式呢？（生说，师板书8+5）
2. 小组合作交流，动手用小棒摆。
要求在摆好后，把你的摆法说给同桌听，在听人讲话时，要学会倾听，这是一种尊重他人的表现。
3. 指名演示过程（师板演过程）
由于学生有了9加几的基础，所以很容易用“凑十法”来解决这个问题，请用凑十法的小组，到前面演示。
4. 小结
你们说的几种方法都很好，这几种方法中你喜欢哪一种就用哪一种，但是凑十法是一种比较简便的方法。
5. 比较8加几和9加几的异同。
（四）尝试独立学习
1. 生独立完成P103页例2。
现在请同学把书翻到103页，用你喜欢的方法，完成例2，把得数写到书上。
2.汇报计算方法。
3.小结。
鼓励用多种方法来计算。
（五）总结算法，发散思维
1. 出示情境图（课件演示有八只蜜蜂，又飞来九只蜜蜂）
在公园的花丛中，盛开着五颜六色的鲜花，它们把蜜蜂都引来了，你们看，又来一群，你能根据这幅图列一个算式吗？
2. 列式
谁能列式解答？（生说，师板书）
3. 自学
这道题中的同学，想出了3种方法解答，可是他们没有完成，你能帮助他们完成吗？
4. 交流
把你喜欢的算法，说给你同桌听。
5. 指名汇报（师课件演示）
6. 小结。
我们在计算8加几时，可以把另一个加数分成2和几，和8凑成10再计算，也可以把8拆分与另一个加数组成10再计算，也可以用以前学过的知识，比如9+8=17,8+9=17等多种方法来计算，在以后的学习中，你认为哪种好，就用哪一种做题。
三、应用新知，解决问题
（一）创设数学迷宫情境
师：我们下一个观光地点是天赐湖，想到天赐湖要走过一座数学迷宫，想走出迷宫就必须解答这里的数学问题，同学们有信心走出迷宫吗？师讲解走迷宫的方法。
（课件出示题目）
1. P104做一做第2题
2. P104做一做第1题
3. P104做一做第3题
（二）创设游天赐湖情境
师：同学们，经过我们共同的努力，顺利走出了迷宫，来到了美丽的天赐湖，你看见了什么？这些小动物在欢迎我们呢，他们看见同学们来了，非常高兴，这一高兴不要紧，他们忘记了回家的路，你们愿意帮助他们找到回家的路吗？
连线题（课件演示）
四、课堂总结，画龙点睛
愉快的一节课很快过去了，你学会了什么？那么8、7、6加几是怎么样计算的呢？我们可以把其中一个加数拆开和8、7、6凑成10，然后再计算，可以用数数的方法，无论用哪一种方法都可以，看来这节课同学们收获可真不少啊！。
人教新课标一年级数学上册8.2《8、7、6加几》说课稿
人教新课标一年级数学上册8.2《8、7、6加几》说课稿一. 教材分析人教新课标一年级数学上册8.2《8、7、6加几》是本册教材中的一个重要内容，主要让学生通过学习，掌握加法的基本运算方法，培养学生的运算能力和逻辑思维能力。
本节课的内容紧密联系学生的生活实际，让学生在实际情境中感受加法的意义，体验学习的乐趣。
二. 学情分析一年级的学生刚刚开始接触数学运算，对于加法的基本概念和运算方法还比较陌生。
但是，这个年龄段的学生好奇心强，好动，善于模仿，对于直观形象的物体有较大的兴趣。
因此，在教学过程中，我将以情境导入，引导学生通过观察、操作、交流等方式，掌握加法的基本运算方法。
三. 说教学目标1.知识与技能：学生能够理解加法的意义，掌握8、7、6加几的运算方法，能够熟练地进行计算。
2.过程与方法：通过观察、操作、交流等活动，培养学生的问题解决能力和合作交流能力。
3.情感态度与价值观：激发学生学习数学的兴趣，培养学生的自信心，让学生感受数学与生活的紧密联系。
四. 说教学重难点1.教学重点：学生能够理解加法的意义，掌握8、7、6加几的运算方法。
2.教学难点：学生能够灵活运用加法运算方法，解决实际问题。
五. 说教学方法与手段1.教学方法：采用情境教学法、游戏教学法、分组合作教学法等，激发学生的学习兴趣，提高学生的学习积极性。
2.教学手段：利用多媒体课件、教具、学具等，为学生提供丰富的学习资源，帮助学生直观地理解加法运算。
六. 说教学过程1.情境导入：通过展示一个有趣的动画故事，引出本节课的主题，激发学生的学习兴趣。
2.观察操作：学生观察动画中的场景，发现其中的数学问题，并尝试用加法运算解决。
3.交流讨论：学生分组讨论，分享自己的解题方法，互相学习，互相启发。
4.总结规律：引导学生总结8、7、6加几的运算方法，形成规律。
5.练习巩固：设计一些有趣的练习题，让学生在游戏中巩固所学知识。
6.应用拓展：设计一些实际问题，让学生运用所学知识解决，感受数学与生活的联系。
一年级上册数学教案-8.28、7、6加几-人教新课标
一年级上册数学教案－8.2 8、7、6加几人教新课标教案内容：一、教学内容今天我们要学习的是人教新课标一年级上册数学的第八章第二节，主要内容是7、6加几的计算。
我们将通过例题和练习来掌握这个计算方法。
二、教学目标通过本节课的学习，学生能够理解7、6加几的计算方法，并能够熟练地进行计算。
三、教学难点与重点重点是让学生掌握7、6加几的计算方法，难点是让学生能够理解并运用这个计算方法。
四、教具与学具准备我已经准备好了黑板、粉笔、练习本等教具和学具，供我们在课堂上使用。
五、教学过程1. 实践情景引入：我会通过一个实际的情景，比如我们去买水果，让学生理解加法的意义。
2. 例题讲解：我会用具体的例题来讲解7、6加几的计算方法，让学生通过观察和思考，理解并掌握计算方法。
3. 随堂练习：我会给出一些实际的练习题，让学生运用所学的计算方法，进行实际的计算。
4. 作业布置：我会布置一些相关的作业，让学生回家后进行巩固练习。
六、板书设计我会根据讲解的内容，设计相应的板书，帮助学生理解和记忆。
七、作业设计（1）7 + 3 =（2）6 + 4 =2. 答案：（1）7 + 3 = 10（2）6 + 4 = 10八、课后反思及拓展延伸通过本节课的学习，我发现大部分学生已经能够理解和掌握7、6加几的计算方法，但在实际操作中，还有一些学生会出现计算错误。
在课后，我会针对这些学生进行个别辅导，帮助他们巩固所学知识。
对于拓展延伸，我会在下一节课中，通过更多的练习题，让学生进一步巩固7、6加几的计算方法，并逐步引入更复杂的计算题目。
重点和难点解析一、实践情景引入在实践情景引入环节，我选择了学生们日常生活中常见的情境——买水果。
这个情景能够让学生们直观地理解加法的意义，即把两种数量合并在一起的总数。
例如，如果一个苹果是1元，那么买2个苹果就需要支付2元。
通过这个情景，学生们能够更好地理解加法的基本概念。
二、例题讲解在讲解7、6加几的例题时，我会用具体的数字和图像来说明。
人教新课标一年级数学上册8.2《8、7、6加几》说课稿
人教新课标一年级数学上册8.2《8、7、6加几》说课稿一. 教材分析《8、7、6加几》是人教新课标一年级数学上册第八单元第二节的内容。
这一节主要让学生掌握6、7、8加一位数的计算方法，进一步培养学生的加法运算能力。
教材通过生动的图片和实际情境，引导学生理解加法的意义，并运用数数、拆分、合并等方法进行计算。
教材还注重培养学生的观察能力、思考能力和动手操作能力，为学生进一步学习加减法运算打下基础。
二. 学情分析一年级的学生已经具备了一定的数数能力，对加法运算有了初步的认识。
但在实际操作中，部分学生可能还存在对加法意义的理解不深、计算方法不熟练等问题。
此外，学生的观察能力、思考能力和动手操作能力各有差异，需要在教学过程中加以关注和引导。
三. 说教学目标1.知识与技能目标：学生会正确计算6、7、8加一位数的题目，能运用不同的方法进行计算。
2.过程与方法目标：学生通过观察、思考、动手操作等过程，掌握加法运算的方法，提高解决问题的能力。
3.情感态度与价值观目标：学生体验数学学习的乐趣，培养积极主动参与数学活动的意识，增强团队协作能力。
四. 说教学重难点1.教学重点：学生掌握6、7、8加一位数的计算方法，能正确进行计算。
2.教学难点：学生能灵活运用不同的方法进行计算，理解加法的意义。
五. 说教学方法与手段本节课采用情境教学法、启发式教学法、分组合作教学法等多种教学方法。
通过生动的情境导入，激发学生的学习兴趣；运用启发式教学，引导学生思考和探索；分组合作教学，培养学生的团队协作能力和沟通能力。
此外，还运用数数、拆分、合并等手段，帮助学生理解和掌握计算方法。
六. 说教学过程1.导入新课：通过图片展示，引导学生观察和描述图片中的情境，引出加法运算的需求。
2.探索计算方法：引导学生尝试计算6、7、8加一位数的题目，鼓励学生运用不同的方法进行计算，如数数、拆分、合并等。
3.交流分享：邀请学生分享自己的计算方法，引导学生相互学习、交流，总结出加法运算的规律。
一年级上册数学教案第八单元第5课时8、7、6加几(2)人教版
土木工程专业英语翻译土木工程专业外语翻译专业：铁道工程学号：20137084姓名：郭翔西南交通大学峨眉校区2016 年 6 月16 日Building construction concrete crack ofprevention and processingAbstractThe crack problem of concrete is a widespread existence but again difficult in solve of engineering actual problem, this text carried on a study analysis to a little bit familiar crack problem in the concrete engineering, and aim at concrete the circumstance put forward some prevention, processing measure. Keyword:Concrete crack prevention processingForewordConcrete's ising 1 kind is anticipate by the freestone bone, cement, water and other mixture but formation of the in addition material of quality brittleness not and all material.Because the concrete construction transform with oneself, control etc. a series problem, harden model of in the concrete existence numerous tiny hole, spirit cave and tiny crack, is exactly because these beginning start blemish of existence just make the concrete present one some not and all the characteristic of quality.The tiny crack is a kind of harmless crack and accept concrete heavy, defend Shen and a little bit other use function not a creation to endanger.But after the concrete be subjected to lotus carry, difference in temperature etc. function, tiny crack would continuously of expand with connect, end formation we can see without the aid of instruments of macro view the crack be also the crack that the concrete often say in the engineering.Concrete building and Gou piece usually all take sewer to make of, because of crack of existence and development usually make inner part of reinforcing bar etc. material creation decay, lower reinforced concrete material of loading ability, durable and anti- Shen ability, influence building of external appearance, service life, severity will threat arrive people's life and property safety.A lot of all ofcrash of engineerings is because of the unsteady development of the crack with the result that.Modern age science research with a great deal of of the concrete engineering practice certificate, in the concrete engineering crack problem is ineluctable, also acceptable in certainly of the scope just need to adopt valid of measure will it endanger degree control at certain of scope inside.The reinforced concrete norm is also explicit provision:Some structure at place of dissimilarity under the condition allow existence certain the crack of width.But at under construction should as far as possible adopt a valid measure control crack creation, make the structure don't appear crack possibly or as far as possible decrease crack of amount and width, particularly want to as far as possible avoid harmful crack of emergence, insure engineering quality thus.Concrete crack creation of the reason be a lot of and have already transformed to cause of crack:Such as temperature variety, constringency, inflation, the asymmetry sink to sink etc. reason cause of crack;Have outside carry the crack that the function cause;Protected environment not appropriate the crack etc. caused with chemical effect.Want differentiation to treat in the actual engineering, work°out a problem according to the actual circumstance.In the concrete engineering the familiar crack and the prevention1.Stem Suo crack and preventionStem the Suo crack much appear after the concrete protect be over of a period of time or concrete sprinkle to build to complete behind of around a week.In the cement syrup humidity of evaporate would creation stem Suo, and this kind of constringency is can't negative.Stem Suo crack of the creation be main is because of concrete inside outside humidity evaporate degree dissimilarity but cause to transform dissimilarity of result:The concrete is subjected to exterior condition of influence, surface humidity loss lead quick, transform bigger, inner part degree of humidity variety smaller transform smaller, bigger surface stem the Suo transform to be subjected to concrete inner part control, creation more big pull should dint but creation crack.The relative humidity is more low, cement syrup body stem Suo more big, stem the Suo crack be more easy creation.Stemthe Suo crack is much surface parallel lines form or the net shallow thin crack, width many between 0.05-0.2 mm, the flat surface part much see in the big physical volume concrete and follow it more in thinner beam plank short to distribute.Stem Suo crack usually the anti- Shen of influence concrete, cause the durable of the rust eclipse influence concrete of reinforcing bar, under the function of the water pressure dint would creation the water power split crack influence concrete of loading dint etc..Concrete stem the Suo be main with water ash of the concrete ratio, the dosage of the composition, cement of cement, gather to anticipate of the dosage of the property and dosage, in addition etc. relevant. Main prevention measure:While being to choose to use the constringency quantity smaller cement, general low hot water mire and powder ash from stove cement in the adoption, lower the dosage of cement.Two is a concrete of stem the Suo be subjected to water ash ratio of influence more big, water ash ratio more big, stem Suo more big, so in the concrete match the ratio the design should as far as possible control good water ash ratio of choose to use, the Chan add in the meantime accommodation of reduce water.Three is strict control concrete mix blend with under construction of match ratio, use of concrete water quantity absolute can't big in match ratio design give settle of use water quantity.Four is the earlier period which strengthen concrete to protect, and appropriate extension protect of concrete time.Winter construction want to be appropriate extension concrete heat preservation to overlay time, and Tu2 Shua protect to protect.Five is a constitution the accommodation is in the concrete structure of the constringency sew.2.The Su constringency crack and preventionSu constringency is the concrete is before condense, surface because of lose water quicker but creation of constringency.The Su constringency crack is general at dry heat or strong wind the weather appear, crack's much presenting in the center breadth, both ends be in the centerthin and the length be different, with each other not coherent appearance.Shorter crack general long 20-30 cm, the longer crack can reach to a 2-3 m, breadth 1-5 mm.It creation of main reasonis:The concrete is eventually almost having no strength or strength before the Ning very small, perhaps concrete just eventually Ning but strength very hour, be subjected to heat or compare strong wind dint of influence, the concrete surface lose water to lead quick, result in in the capillary creation bigger negative press but make a concrete physical volume sharply constringency, but at this time the strength of concrete again can't resist its constringency, therefore creation cracked.The influence concrete Su constringency open the main factor of crack to have water ash ratio, concrete of condense time, environment temperature, wind velocity, relative humidity...etc..Main prevention measure:One is choose to use stem the Suo value smaller higher Huo sour salt of the earlier period strength or common the Huo sour brine mire.Two is strict the control water ash ratio, the Chan add to efficiently reduce water to increment the collapse of concrete fall a degree and with easy, decrease cement and water of dosage.Three is to sprinkle before building concrete, water basic level and template even to soak through.Four is in time to overlay the perhaps damp grass mat of the plastics thin film, hemp slice etc., keep concrete eventually before the Ning surface is moist, perhaps spray to protect etc. to carry on protect in the concrete surface.Five is in the heat and strong wind the weather to want to establish to hide sun and block breeze facilities, protect in time.3.Sink to sink crack and preventionThe creation which sink to sink crack is because of the structure foundation soil quality not and evenly, loose soft or return to fill soil dishonest or soak in water but result in the asymmetry sink to decline with the result that;Perhaps because of template just degree shortage, the template propped up to once be apart from big or prop up bottom loose move etc. to cause, especially at winter, the template prop up at jelly soil up, jelly the soil turn jelly empress creation asymmetry to sink to decline and cause concrete structure creation crack.This kind crack many is deep enter or pierce through sex crack, it alignment have something to do with sinking to sink a circumstance, general follow with groundperpendicular or present 30 °s-45 ° Cape direction development, bigger sink to sink crack, usually have certain of wrong, crack width usually with sink to decline quantity direct proportion relation.Crack width under the influence of temperature variety smaller.The foundation after transform stability sink to sink crack also basic tend in stability.Main prevention measure:One is rightness loose soft soil, return to fill soil foundation a construction at the upper part structure front should carry on necessity of Hang solid with reinforce.Two is the strength that assurance template is enough and just degree, and prop up firm, and make the foundation be subjected to dint even.Three is keep concrete from sprinkle infusing the foundation in the process is soak by water.Four is time that template tore down to can't be too early, and want to notice to dismantle a mold order of sequence.Five is at jelly soil top take to establish template to notice to adopt certain of prevention measure.4.Temperature crack and preventionTemperature crack much the occurrence is in big surface or difference in temperature variety of the physical volume concrete compare the earth area of the concrete structure.Concrete after sprinkling to build, in the hardening the process, cement water turn a creation a great deal of of water turn hot, .(be the cement dosage is in the 350-550 kg/m 3, each sign square the rice concrete will release a calories of 17500-27500 kJ and make concrete internal thus the temperature rise to reach to 70 ℃or so even higher)Because the physical volume of concrete be more big, a great deal of of water turn hot accumulate at the concrete inner part but not easy send forth, cause inner part the temperature hoick, but the concrete surface spread hot more quick, so formation inside outside of bigger difference in temperature, the bigger difference in temperature result in inner part and exterior hot the degree of the bulge cold Suo dissimilarity, make concrete surface creation certain of pull should dint.When pull should dint exceed the anti- of concrete pull strength extreme limit, concrete surface meeting creation crack, this kind of crack much occurrence after theconcrete under construction period.In the concrete of under construction be difference in temperature variety more big, perhaps is a concrete to be subjected to assault of cold wave etc., will cause concrete surface the temperature sharply descend, but creation constringency, surface constringency of the concrete be subjected to inner part concrete of control, creation very big of pull should dint but creation crack, this kind of crack usually just in more shallow scope of the concrete surface creation.The alignment of the temperature crack usually none settle regulation, big area structure the crack often maneuver interleave;The size bigger structure of the beam plank length, the crack run parallel with short side more;Thorough with pierce through sex of temperature crack general and short side direction parallelism or close parallelism, crack along long side cent the segment appear, in the center more airtight.Crack width the size be different, be subjected to temperature variety influence more obvious, winter compare breadth, summer more narrow.The concrete temperature crack that the heat inflation cause is usually in the center the thick both ends be thin, but cold Suo crack of thick thin variety not too obvious.The emergence of the this kind crack will cause the rust eclipse of reinforcing bar, the carbonization of concrete, the anti- jelly which lower concrete melt, anti- tired and anti- Shen ability etc..Main prevention measure:One is as far as possible choose to use low hot or medium hot water mire, like mineral residue cement, powder ash from stove cement...etc..Two is a decrease cement dosage, cement dosage as far as possible the control is in the 450 kg/m 3 following.Three is to lower water ash ratio, water ash of the general concrete ratio control below 0.6.Four is improvement the bone anticipate class to go together with, the Chan add powder ash from stove or efficiently reduce water etc. to come to reduce cement dosage and lower water to turn hot.Five is an improvement concrete of mix blend to process a craft, lower sprinkle of concrete to build temperature.Six is the in addition that the Chan add a have of fixed amount to reduce water and increase Su, slow Ning etc. function in the concrete, improvement the concrete mix to match a thing of mobility,protect water, lower water to turn hot, postpone hot Feng of emergence time.Seven is the heat season sprinkle to build can the adoption take to establish to hide sun plank etc. assistance measure control concrete of Wen Sheng, lower to sprinkle temperature of build the concrete.Eight is the temperature of big physical volume concrete should the dint relate to structure size, concrete structure size more big, temperature should dint more big, so want reasonable arrangement construction work preface, layering, cent the piece sprinkle to build, for the convenience of in spread hot, let up control.Nine is at great inner part constitution of the physical volume concrete cool off piping, cold water perhaps cold air cool off, let up concrete of inside outside difference in temperature.Ten is the supervision which strengthen concrete temperature, adopt to cool off in time, protection measure.11 is to reserve temperature constringency to sew.12 is to let up to control, sprinkle proper before building concrete in the Ji rock and old concrete top build a 5 mm or so sand mat a layer or usage asphalt etc. material Tu2 Shua.13 is to strengthen concrete to protect, the concrete after sprinkle build use moist grass Lian in time, hemp slice's etc. overlay, and attention sprinkle water to protect, appropriate extension protect time, assurance the concrete surface be slow-moving cool off.At the cold season, concrete surface should constitution heat preservation measure, in order to prevent cold wave assault.14 is the allocation be a little amount in the concrete of reinforcing bar perhaps add fiber material concrete of temperature crack control at certain of scope inside.5.Crack and prevention that the chemical reaction causeAlkali bone's anticipating the crack that reaction crack and reinforcing bar rust eclipse cause is the most familiar in the reinforced concrete structure of because of chemical reaction but cause of crack.The concrete blend a future reunion creation some alkalescence ion, these ion with some activity the bone anticipate creation chemical reaction and absorb surroundings environment in of water but the physical volume enlarge, make concrete crisp loose, inflation open crack.In this kind of crack general emergenceconcrete structure usage period, once appear very difficult remediable, so should at under construction adopt valid the measure carry on prevention.Main of prevention measure:While being to choose to anticipate with the alkali activity small freestone bone.Two is the in addition which choose to use low lye mire with low alkali or have no alkali.Three is the Chan which choose to use accommodation with anticipate to repress an alkali bone to anticipate reaction. Because the concrete sprinkle to build, flap Dao bad perhaps is a reinforcing bar protection layer thinner, the harmful material get into concrete to make reinforcing bar creation rust eclipse, the reinforcing bar physical volume of the rust eclipse inflation, cause concrete bulge crack, the crack of this kind type much is a crack lengthways, follow the position of reinforcing bar ually of prevent measure from have:One is assurance reinforcing bar protection the thickness of the layer.Two is a concrete class to go together with to want good.Three is a concrete to sprinkle to note and flap Dao airtight solid.Four is a reinforcing bar surface layer Tu2 Shua antisepsis coating.Crack processingThe emergence of the crack not only would influence structure of whole with just degree, return will cause the rust eclipse of reinforcing bar, acceleration concrete of carbonization, lower durable and anti- of concrete tired, anti- Shen ability.Therefore according to the property of crack and concrete circumstance we want differentiation to treat, in time processing, with assurance building of safety usage.The repair measure of the concrete crack is main to have the following some method:Surface repair method, infuse syrup, the Qian sew method, the structure reinforce a method, concrete displacement method, electricity chemistry protection method and imitate to living from heal method.Surface repair the method be a kind of simple, familiar of repair method, it main be applicable to stability and to structure loading the ability don't have the surface crack of influence and deep enter crack of processing.The processingmeasure that is usually is a surface in crack daubery cement syrup, the wreath oxygen gum mire or at concrete surface Tu2 Shua paint, asphalt etc. antisepsis material, at protection of in the meantime for keeping concrete from continue under the influence of various function to open crack, usually can adoption the surface in crack glue to stick glass fiber cloth etc. measure.1, infuse syrup, the Qian sew methodInfuse a syrup method main the concrete crack been applicable to have influence or have already defend Shen request to the structure whole of repair, it is make use of pressure equipments gum knot the material press into the crack of concrete, gum knot the material harden behind and concrete formation one be whole, thus reinforce of purpose.The in common use gum knot material has the cement the syrup, epoxy, A Ji C Xi sour ester and gather ammonia ester to equalize to learn material.The Qian sew a method is that the crack be a kind of most in common use method in, it usually is follow the crack dig slot, the Qian fill Su in the slot or rigid water material with attain closing crack of purpose.The in common use Su material has PVC gum mire, plastics ointment, the D Ji rubber etc.;In common use rigid water material is the polymer cement sand syrup.2, the structure reinforce a methodWhen the crack influence arrive concrete structure of function, will consideration adopt to reinforce a method to carry on processing to the concrete structure.The structure reinforce medium in common use main have the following a few method:The piece of enlargement concrete structure in every aspect accumulate, outside the Cape department of the Gou piece pack type steel, adoption prepare should the dint method reinforce, glue to stick steel plate to reinforce, increase to establish fulcrum to reinforce and jet the concrete compensation reinforce.3, concrete displacement methodConcrete displacement method is processing severity damage concrete of a kind of valid method, this method be first will damage of the concrete pick and get ridof, then again displacement go into new of concrete or other material.The in common use displacement material have:Common concrete or the cement sand syrup, polymer or change sex polymer concrete or sand syrup.4, the electricity chemistry protection methodThe electricity chemistry antisepsis is to make use of infliction electric field in lie the quality of electricity chemical effect, change concrete or reinforced concrete the environment appearance of the place, the bluntness turn reinforcing bar to attain the purpose of antisepsis.Cathode protection method, chlorine salt's withdrawing a method, alkalescence to recover a method is a chemistry protection method in three kinds of in common use but valid method.The advantage of this kind of method is a protection method under the influence of environment factor smaller, apply reinforcing bar, concrete of long-term antisepsis, since can used for crack structure already can also used for new set up structure.5, imitate to living from legal moreImitate to living from heal the method be a kind of new crack treatment, its mimicry living creature organization secrete a certain material towards suffering wound part auto, but make the wound part heal of function, join some and special composition(such as contain to glue knot of the liquid Xin fiber or capsule) in the concrete of the tradition the composition, at concrete inner part formation the intelligence type imitate to living from heal nerve network system, be the concrete appear crack secrete a parts of liquid Xin fiber can make the crack re- heal.ConclusionThe crack is widespread in the concrete structure existence of a kind of phenomenon, it of emergence not only will lower the anti- Shen of building ability, influence building of usage function, and will cause the rust eclipse of reinforcing bar, the carbonization of concrete, lower the durable of material, influence building of loading ability, so want to carry on to the concrete crackearnest research, differentiation treat, adoption reasonable of the method carry on processing, and at under construction adopt various valid of prevention measure to prevention crack of emergence and development, assurance building and Gou piece safety, stability work.From《CANADIAN JOURNAL OF CIVIL ENGINEERING》建筑施工混凝土裂缝的预防与处理混凝土的裂缝问题是一个普遍存在而又难于解决的工程实际问题，本文对混凝土工程中常见的一些裂缝问题进行了探讨分析，并针对具体情况提出了一些预防、处理措施。
人教新课标一年级数学上册8.2《8、7、6加几》教案2
人教新课标一年级数学上册8.2《8、7、6加几》教案2
一、教学目标
1.能够准确读出数字8、7、6，并能够正确书写。
2.能够通过连加的方式计算8、7、6相加的结果。
3.培养学生的动手能力和思维逻辑能力。
二、教学重难点
1.重点：数字8、7、6的认识和加法计算方法。
2.难点：能够正确连加数字并得到正确结果。
三、教学准备
1.教师准备：数字卡片8、7、6、加号、等号，小板书，教具等。
2.学生准备：铅笔、橡皮、练习本等。
四、教学过程
1. 导入新知识
教师出示数字卡片8、7、6，让学生认识这几个数字，并请几名学生上台念出来。
2. 引入问题
教师出示算式“8＋7＋6＝？”，让学生猜一猜这几个数字相加的结果是多少。
3. 计算过程演示
教师用小板书或黑板上示范如何用连加的方法计算8、7、6相加的结果，并让学生跟着一起操作。
4. 练习环节
1.让学生自己用纸和铅笔计算如下算式：8＋7＋6＝？
2.让学生两人一组相互出题，进行相加练习。
5. 拓展应用
让学生设计自己的加法算式，用“8、7、6”进行计算，并在班级展示。
五、课堂小结
通过本节课的学习，我们学会了用连加的方式计算“8、7、6”的加法。
同时也培养了我们的动手能力和思维逻辑能力。
六、课后作业
1.完成练习本上相关练习。
2.设计并计算自己的加法算式。
以上就是本节课的教学内容，希望同学们能够认真学习，掌握好加法的计算方法，成为小小算术高手！。
人教版一年级数学上册《第八单元 8、7、6加几 第2课时》教案教学设计优秀公开课
8、7、6加几教学内容8、7、6加几教材第92页的内容及练习二十一的第4~10题及思考题。
教学目标1.继续学习8、7、6加几的题,学会用交换加数位置的方法计算。
2.培养学生思维的灵活性。
重点难点掌握用交换加数的方法口算8、7、6加几。
教具学具算式卡片,口算转盘等。
教学过程一学前准备1.计算,同桌说方法。
9+6=8+4=7+5=6+5=2.口算。
9+7=7+6=8+6=9+8=8+5=6+6=9+4=8+7=二探究新知出示例3:8+9=1.学生独立想办法计算。
2.学生汇报,老师板书。
想:8+9=?3.看板书提问。
哪种方法能很快算出得数?为什么?(第三种方法能很快算出得数,因为9+8=17是我们已经学过的,交换9和8的位置,得数不变)4.有哪些题目能用这种方法做?请同桌议论,把你想到的写下来。
5.汇报。
7+9=7+8=6+7=5+6=4+9=6+8=5+7=2+9=4+8=5+9=4+7=3+9=3+8=6+9=5+8=同桌看算式说得数。
三课堂作业新设计1.教材第92页“做一做”的第1~3题。
2.练习二十一的第4题。
3.练习二十一的第7题。
4.练习二十一的第9题。
四思维训练1.2+2+2+7=+72.□和○分别代表什么数?▲=2□+▲=11□=()○+▲=12○=()3.任选1~19各数填进中,使每条直线上的数相加得18。
参考答案课堂作业新设计1.教材第92页“做一做”的第1题:1515教材第92页“做一做”的第2题:131416131416教材第92页“做一做”的第3题:8+3=117+8=152.<<>=>=3.1512185304.494937思维训练1.62.9103.(答案不唯一)可以是教材习题练习二十一5.1631411148161015014131411106.78.略10.略思考题答案不唯一,如:板书设计8、7、6加几8+9=?想:9+8=178+9=17课后反思1.首先引导学生在具体的情境中提出问题,寻找解决问题的方法,初步感知“凑十法”。
人教新课标一年级数学上册8.2《8、7、6加几》教案
人教新课标一年级数学上册8.2《8、7、6加几》教案
一、教学目标
1.能正确说出8、7、6的顺序，并能根据提示将它们加在一起。
2.能够用实物或图形的形式展现8、7、6相加的过程。
3.能够运用加法口诀表背诵8、7、6相加的结果。
4.能够在实际生活中灵活运用8、7、6相加的计算方法。
二、教学重点
1.8、7、6的顺序和相加的结果。
2.用实物或图形展示加法运算过程。
3.加法口诀表的运用。
三、教学准备
1.黑板、彩色粉笔
2.实物或图形的8个小球、7个小球、6个小球
3.加法口诀表
四、教学过程
1. 导入
教师手持8、7、6个小球，让学生观察并说出数量，引导学生完成任务：“8、7、6加几？”
2. 学习教材
教师在黑板上列出8、7、6的数目，让学生根据提示相加，并将结果写在黑板上，引导学生规范书写。
3. 实物展示
教师提供实物小球，让学生亲自操作，将8、7、6个小球相加的过程呈现出来，让学生形象记忆。
4. 口算练习
教师带领学生背诵加法口诀表，深入理解8、7、6的相加结果。
5. 拓展应用
教师给出实际案例，要求学生将8、7、6相加的结果运用到解决问题中，培养学生的综合运用能力。
五、课堂小结
通过本节课程的学习，学生能够掌握8、7、6的相加规律，能够通过实物展示和口算练习更好地理解和运用加法计算。
六、作业布置
完成课后练习册上相关练习并复习加法口诀表。
本教案对一年级学生学习《8、7、6加几》这一数学知识做了详细的教学设计，通过实物展示、口算练习等多种形式，帮助学生深入理解并掌握加法运算的基本原理和方法。
新人教版一年级数学上册5.3《8、7、6加几(2)》教案
【复习旧知，导入新课】1.完成教科书P93“练习二十一”第1题。
师：同学们，你能快速写出每一道算式和得数吗？每人选择一组完成。
学生任意选择一组写算式并计算。
选一些题说一说是怎样用“凑十法”进行计算的，并适时总结“见8想2，见7想3，见6想4”的方法。
课件出示儿歌。
2.课件出示图片，学生独立列出两道算式。
生算式：8+2=10，2+8=10。
师：比较两道算式，你有什么发现？(引导学生说出两道算式中加数的位置交换了，和不变。
)我们也可以运用这种规律来计算。
这节课我们继续来学习8、7、6加几的计算。
［板书课题：8、7、6加几(2)］【经历过程，探究新知】1.计算8+9。
师：(板书8+9)请同学们独立完成计算，并与同桌交流计算方法。
学生独立完成，与同桌交流，教师巡视指导，完成后集体汇报。
生1：可以想8加几得10,10加几得十几？先把8凑成10，把9分成2和7。
生2：可以想9加几得10,10加几得十几？先把9凑成10，把8分成7和1。
教师根据学生的回答板书。
师：除了凑十法，还有其他方法吗？我们学过的哪道题的加数和这道题相同？生：因为9+8=17，所以8+9=17。
(板书)师：我们一起观察这三种计算方法，它们有哪些相同之处？生：前两种方法都是用“凑十法”计算的，第三种方法则是运用交换加数的位置来计算的。
(板书：凑十法交换加数的位置)2.体会应用“交换加数的位置，和不变”的规律计算的优越性。
师：你喜欢第三种方法吗？我们来试一试吧！完成教科书P92“做一做”第2题。
师：怎样能很快说出正确的得数？生：因为7+6=13，所以6+7也等于13；因为8+6=14，所以6+8也等于14；因为9+7=16，所以7+9也等于16。
【巩固练习、拓展提升】1.完成教科书P92“做一做”第1题。
2.完成教科书P92“做一做”第2题。
3.完成教科书P92“做一做”第3题。
课堂小结通过这节课，你有什么收获？作业设计完成本课时的习题。
一年级上册数学教案-第八单元第4课时 8、7、6加几(2)人教版
一年级上册数学教案第八单元第4课时8、7、6加几(2) 人教版教案：一年级上册数学教案第八单元第4课时8、7、6加几(2) 人教版一、教学内容今天我们要学习的是第八单元的第4课时，主题是"8、7、6加几(2)"。
我们将通过例题和练习来巩固加法的基本概念和计算方法。
二、教学目标1. 能够正确计算8、7、6加几的简单算式。
2. 能够理解加法的意义，并能运用到实际情景中。
3. 培养学生的观察能力和解决问题的能力。
三、教学难点与重点本节课的重点是让学生能够熟练计算8、7、6加几的算式，并能够理解其意义。
难点是让学生能够将加法运用到实际情景中，解决实际问题。
四、教具与学具准备为了帮助学生更好地理解和练习，我准备了一些教具和学具，包括数字卡片、小木棍、计算器等。
五、教学过程1. 导入：我先用一个实际情景引入，比如说："如果有6个苹果，再给你2个苹果，你一共有几个苹果？"让学生思考并回答。
2. 讲解：然后我会拿出数字卡片，展示8、7、6加几的算式，并解释其意义。
我会用小木棍来表示加法的过程，让学生直观地理解。
4. 巩固：我会选取一些学生的作业，进行讲解和巩固，确保学生能够掌握加法的基本概念和计算方法。
六、板书设计我会在黑板上写出本节课的重点内容，包括8、7、6加几的算式和其意义。
这样学生可以随时回顾和复习。
七、作业设计课后，我会布置一些练习题，让学生回家后进行巩固和复习。
题目包括：1. 计算8、7、6加几的算式。
2. 用加法解决实际问题，比如说："如果有7个橘子，再给你3个橘子，你一共有几个橘子？"八、课后反思及拓展延伸通过本节课的教学，我觉得学生对于8、7、6加几的算式有了更深入的理解和掌握。
他们在练习中能够正确计算，并能够将加法运用到实际情景中。
但是，我也发现有些学生在解决实际问题时，还是有些困难，需要进一步的练习和引导。
对于拓展延伸，我可以在下一节课中引入一些更复杂的情景，让学生进行思考和解答，提高他们的解决问题的能力。
20以内的进位加法第2课时8、7、6加几(教学设计)-2023-2024学年数学一年级上册人教版
动画片内容：数学小精灵教大家学习进位加法，通过生动的动画演示和有趣的故事情节，让学生轻松掌握进位加法的运算方法。
2.拓展建议
（1）让学生在家里和爸爸妈妈一起玩一些进位加法的游戏，提高自己的运算能力。
（2）鼓励学生利用课余时间阅读一些与数学相关的书籍，如《数学岛历险记》等，培养学生的数学兴趣。
5.采用分组合作学习，让学生在小组内互相交流、讨论和分享进位加法的运算方法，培养学生的团队合作意识和交流能力。
教学过程
1.导入新课
同学们，大家好！上一节课我们学习了20以内的不退位加法，大家掌握得怎么样呢？今天我们要学习一个新的内容——20以内的进位加法。通过本节课的学习，我们要掌握数字8、7、6加几的进位加法运算方法。希望大家能够认真学习，积极参与。
答案：10 - 3 = 7（不退位减法，十位数10减去个位数3等于7，没有退位）
妈妈还剩下7元钱。
题型5：进位加法的混合运算
题目：请计算以下混合运算：
23 + 56 - 89 + 47 =
答案：23 + 56 = 79（进位加法，个位数3加上6等于9，有1个进位）
79 - 89 = -10（退位减法，十位数7减去个位数9等于-2，需要退位，变成-10）
20以内的进位加法第2课时8、7、6加几（教学设计）-2023-2024学年数学一年级上册人教版
授课内容
授课时数
授课班级
授课人数Biblioteka 授课地点授课时间教学内容
本节课的教学内容来自2023-2024学年数学一年级上册人教版教材，第2课时，主要涉及“20以内的进位加法”这一章节。具体内容包括数字8、7、6加几的计算方法。教学目标是让学生掌握20以内数字8、7、6加几的进位加法运算方法，提高学生的数学运算能力。