数字式红外测速仪_课程设计

数字式红外测速仪_课程设计 数字式红外测速仪 一、设计技术指标与要求 1、用红外发光二极管、光敏三极管作为速度转换装置。 2、测速范围:10 – 990转/分。 3、三位数字显示，显示不允许闪烁。 二、设计目的和要求 1、设计目的 本课程设计是在前导性验证性认知实验基础上，进行更高层次的命题设计实验，要求学生在教师指导下独立查阅资料、设计、安装和调试特定功能的电子电路。培养学生利用模拟、数字电路知识，解决电子线路中常见实际问题的能力，使学生积累实际电子制作经验，目的在于巩固基础、注重设计、培养技能、追求创新、走向实用。 2、设计要求 1.以电子技术基础的基本理论为指导，将设计实验分为基础型和系统型两个层次，基础型指基本 单元 初级会计实务单元训练题天津单元检测卷六年级下册数学单元教学设计框架单元教学设计的基本步骤主题单元教学设计 电路设计与调试，系统型指若干个模拟、数字基本单元电路组成并完成特定功能的电子电路的设计、调试; 2.熟悉常用电子仪器操作使用和测试方法; 3.学习计算机软件辅助电路设计方法，能熟练应用电子线路CAD进行电路设计和印刷电路板的设计制作; summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete construction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 4.学习电子系统电路的安装调试技术; 5.拓展电子电路的应用领域，能设计、制作出满足一定性能指标或特定功能的电子电路设计任务。 三、实验原理构思 1、转速概念 转速是旋转物体的转数与时间之比的物理量,是描述各种旋转机械运转技术性能的一个重要参量。转速和频率有共同的量纲,都是单位时间内某一量值(脉冲个数、转数) 出现的次数,从理论上讲,转速值可以直接和频率值进行比对。测时计数是转速计量的基本方法。 测定一定单位时间内旋转物体转过的圈数即频率，可等价为所测旋转物体此时的转速。 2、光电式红外测速仪 经查阅资料知道目前在光电式转速表方面使用的 检测 工程第三方检测合同工程防雷检测合同植筋拉拔检测方案传感器技术课后答案检测机构通用要求培训 装置有两种: a. 采用转速 标准 excel标准偏差excel标准偏差函数exl标准差函数国标检验抽样标准表免费下载红头文件格式标准下载 装置,将定向反射纸贴于装置的测速盘上,由转速标准装置通过测速盘输出标准转速,进行检测。 采用脉冲光源测 b. 速装置来检测光电式转速表。这类检测设备通常由频率信号发生器、 频率计数计及一个发光二极管组成。 两种检测装置的工作原理有质的差别。脉冲光源测速装置能否做为标准,在转速界争议较大。 本课程设计即可采用红外发光二极管和光敏三极管作为速度转换summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete construction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 装置来测取旋转物体转速。可将红外发光二极管固定于旋转物体(假设为汽车车轮)定轴上，在转轴上安装一遮光板，在遮光板上可打一个小孔，在转轮旋转时，当发光二极管、小孔、光敏三极管在一条轴线上时小洞才有红外光通过，其他时间则由于挡板作用，没有光通过。光敏电阻接收红外光后转化为一个脉冲，产生一个脉冲则说明转一圈。这样只需要测量一分钟内光敏三极管输出脉冲个数，就可以知道车轮的转速了。 四、设计 方案 气瓶 现场处置方案 .pdf气瓶 现场处置方案 .doc见习基地管理方案.doc关于群访事件的化解方案建筑工地扬尘治理专项方案下载 构思 1、方案一 被测旋转物体 光电转换装置 计数器 译码转换 LED显示 图-1 方案一 流程 快递问题件怎么处理流程河南自建厂房流程下载关于规范招聘需求审批流程制作流程表下载邮件下载流程设计 图 2方案二 光电转换装置 计数器 被测旋转物体 体 60s时钟电路 译码转换 LED显示 图-2 方案二流程图 通过比较可知因为方案二加入了60s时钟电路，同时具备了时钟计 数功能，每60s自动清零，停止计数，三位数码显示管示数即为所测旋转物体转速。所以本课程设计采用方案二进行设计。 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete const3 ruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 五、设计原理及步骤 1、数字式红外测速仪原理框图 被测旋转物体 光电转换装置 计数器 60s时钟电路 译码转换 LED显示 图-3 数字式红外测速仪原理框图 2、光电转换模拟电路 图-4 光电转换电路模拟图 当合上开关时，红外发光二极管导通并发射红外线，当遮光板上小洞正好与发光二极管和光敏三极管在一条线上时，光敏三极管接收红外线，并产生一高电平脉冲信号，输出给计数器。 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete construction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 3、三极管产生的高电平信号波形图，如下图 图-5 三极管产生的高电平信号波形图 实际使用时需用施密特触发器对三极管产生的高电平信号整形，同时输出一高低电平信号。 图-6 施密特触发器 4、输出脉冲模拟计数 可用控制开关来手动模拟小洞转过一圈时输出一脉冲并计数情景，如下图 上面显示管示数为2，下面显示管示数为3。 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete const5 ruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 图-7 输出脉冲模拟计数 工作原理简述:原先显示译码器示数为2，合上开关A时输出一脉冲 信号给计数器，断开时则显示译码器示数为3，即为一次脉冲一次计 数。 如果用手动来合上断开开关并计时，而且需要计数一分钟在操作中很 难实现，因此出现问题。 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete construction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 5、脉冲计数问题解决 可用555定时器产生1HZ即1s脉冲信号接入计数器进行计数，计数器采用2个十进制计数器74LS160D实现2位计数,当计数到60，停止计数，实现一分钟定时功能。 6、1s脉冲发生器电路-555定时器 该555定时器产生1s时钟脉冲，用于下面计数器计数。 图-8 1s脉冲发生器电路-555定时器 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete const7 ruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 7、六十进制计数器 定时计数电路 图-9 60s定时计数电路 用555定时器输出1HZ(1s)脉冲信号接入计数器进行计数，计数 器采用2个十进制计数器74LS160D组成60进制计数器实现2位计 数,当计数到60，即停止计数。 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete construction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 8、译码显示电路 图-10 三位译码显示电路图 采用了3片十进制计数器74LS160D，可对输入脉冲信号进行计数，输出结果即为所测转速。 而且计数至990时自动清零，即实现了测速范围 (10~990转/分)。当计数为990时，给出低电平将三片74LS160D全部清零，以等待下一个脉冲信号重新计数。 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete const9 ruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 六、数字式红外测速仪总电路图 图-11 数字式红外测速仪总电路图 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete construction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 总电路图在实际仿真中对原先电路图进行了一些改进，可自动实现一分钟计数功能，而原先总电路还需手动给脉冲信号，人工计时，故减少了工作量。 七、所用器件 红外发光二极管、光敏三极管各一片， 1K电阻、开关、与非、非门、与非门若干， 555定时器一片， 74LS160D计数器五片， 施密特触发器一片， DCD -HEX型数码显示管五片， 电源若干。 八、设计总结 1、该电路最大的优点是运用74LS160，相比其他计数器速度快一些，而且也提高计数准确度;红外管的灵敏度高，从而减少了测试结果的误差;它是一种非接触型的测试器，使用安全，方便。整个电路主要以数字电路为主，因此相对模拟电路来说误差还是小很多。 2、仿真实验遇到过一些问题，因本次设计的电路图，有些部分无法仿真，因为红外线照射光敏三级管在软件里并未看到明显的效果，但是可以模拟一下，就是用一个开关不断的断合来模拟下降沿脉冲信号，或者通过一个下降沿的函数信号发生器来模拟使计数器工作。 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete const11 ruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 4、一些元器件不知道怎么连接，对于计数器的清零等问题都是通过翻阅资料、上网、与同学讨论后并解决，才有最终的总电路图。 5、总之，该电路结构简单，只能用于要求很低的场合，而对于要求比较高的电路是不实用的。因此还有许多细节的地方需要改进。 九、设计心得体会 通过这次课程设计，我对红外二极管和光敏三极管组合测转速这种方法有了一定的实验操作经验，虽然实验是用Mulitisim 12 虚拟实验室模拟得出的，在实际实验室中应该也会有出现这种效果。 这次课程设计使我更熟练的使用Mulitisim 类型虚拟实验室软件，也掌握了电子线路设计的基本思想和方法。根据设计目的和用途先进行原理的转换，再确定电路方案，根据原理图选择所需要的器件，最终连线仿真测试，测试中再不断完善电路和方案。有些在课本中学到的元器件这次也算真正的用上了，也使我对一些元器件有了新的认识，加深了对它们各自功能的理解，理论与实践相结合，这是一次很好的锻炼机会，即巩固了模拟电子技术里一部分知识，也加强了最近学过的数字电子技术部分内容的理解。 这次试验能成功首先要感谢老师平时的教导和这几天的指导，也是这次课程设计加强了自己的动手能力，也对后续课程学习有很大帮助。这次课程设计我学到了很多。 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete construction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 参考文献 1、《数字电子技术基础》第五版， 高等教育出版社，阎石 2、《模拟电子技术基础》第四版， 高等教育出版社，童诗白、华成英 3、《虚拟电子实验室》-Mulitisim 7 ， 人民邮电出版社，路而红 4、《模电数电基础实验及Multisim 7仿真》，浙江大学出版社，黄培根、朱维婷等 @yhb hncj summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete const13 ruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete construction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into