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1、In order to ensure normal teaching order, protecting students healthy growth, ensuring that national (property) is not lost, to prevent or minimize the occurrence of safety accidents, follow the prevent, rescue each other, ensure safety and reduce losses principle, according to the local conditions,
2、 make the management system. 1, the principal is the responsibility of school safety, school security under the leadership of President security work leading group. The head teacher to the leadership team is responsible for, implementation of the accountability system. 2, school monthly student know
3、ledge about safety education, education should be diversified in the form every safety education for students of classes per week should be targeted. To carry on emergency issues dealing with education in General, self-help and mutual rescue knowledge. Emergency calls (such as 110, 119, 122, 120, an
4、d so on) use common sense in education. 3, the establishment of major accident reporting system. School students report major accident within an hour of education; student run and disappearances to report; report of the accident to a written report in triplicate, a correctional centre, a police stat
5、ion, a township peoples Government shall not conceal the accident. 4 week, teachers are on duty system, establish and improve the leadership values; strengthen the education, management of teaching activities in schools to ensure normal teaching order; responsible for school safety leadership always
6、 maintained close contact and district police stations, canvassing support from the police station on school safety and help. 5, strengthening teachers moral education, establish a dedicated love, improving education quality, observe the students psychological changes at any time and take preventive
7、 measures, no corporal punishment and covert corporal punishment on students, student out of the classroom, schools may not be. 6, units or departments use student Street propaganda or participate in the celebrations, as well as participating in other social work, without approval of the Correctiona
8、l Centre, school principals consent, without organization. Without the approval of relevant departments, may organize students to participate in fire fighting, disaster relief and so on. 7, schools should educate students to obey the school rules and regulations, on time, on time home to prevent acc
9、idents. 8, school to school inspections on a regular basis, found hidden in time, and in severe cases, it is hard to eliminate immediately closed, and reported to the local peoples Government, education, and rule of law section. 9, the school should always check the internal walls, retaining walls,
10、ponds, railings, handrails, doors, Windows, staircases and a variety of sports, extracurricular activities, facilities such as fire safety, infrastructure security, unsafe facility to immediately repair and demolition to ensure that teachers and students work, learn, live venues and facilities are s
11、afe and reliable. Song Lin Xiang Liu Jia ping elementary school March 2016 song Lin Xiang Liu Jia ping primary school fire safety systems to enhance fire safety, protection of public property and the life and property safety of teachers and students, school fire safety into day-to-day management, is
12、 developing the following fire safety system. 1, strengthen fire safety education of the whole school. According to the requirements of the Fire Services Act, so that everyone has of keeping fire control safety, protecting fire control facilities, fire prevention, reports of fire混凝土拆模时间 规范专业讲解1.拆模时间
13、依据、梁、板模板的拆模时间依据：同条件混凝土试块试压强度、柱、墙模板的拆模时间为混凝土达到终凝后、拆模不影响混凝土质量为宜。2.底模拆除时的混凝土强度要求混凝土结构工程施工质量验收规范（GB502042002）4.3.1规定，拆除底模和支架时的混凝土强度要求：1、板A：构件跨度不大于2米，要求达到设计的混凝土立方体抗压强度标准值的百分率应不小于50%；B：构件跨度在区间（2m，8m的，要求上述值不小于75%；C：对于构件跨度大于8米的，要求达到100%2、梁、拱、壳A：跨度不大于8米的构件 要求达到75%以上的百分率；B：跨度大于8米的构件 ，要求强度达到100%3、悬臂构件，均要求设计强度达
14、到100%。侧模拆除的混凝土强度应保证其混凝土表面和棱角不受损伤3.拆模时间一般是多少天？（1）混凝土侧模拆模时间一般只要保证表面及棱角不因拆模而受到损伤就可以了，一般情况下混凝土浇筑完一天后就可以拆了，从实际情况来看也是尽早拆拆模效果比较好。（2）底模就根据GB50204-2002中的要求。一般来说在混凝土施工时现场留置同条件拆模试块，在估计时间差不多时进行试压，试压达到要求后经监理同意后进行拆除（因为需要填报拆模检验批，里面有拆模强度一项，要求填的就是拆模试块强度）。（3）拆模时间柱、墙、梁不做支撑的侧模：12小时单向版（净跨距里3-6M，活载重不大于静载重）：7D单向版（净跨距里3-6M
15、，活载重大于静载重）：4D单向版（净跨距里6M，活载重不大于静载重）：10D单向版（净跨距里6M，活载重大于静载重）：7D梁底模（净跨距里3-6M，活载重不大于静载重）：14D梁底模（净跨距里3-6M，活载重不大于静载重）：7D梁底模（净跨距里6M，活载重不大于静载重）：21D梁底模（净跨距里6M，活载重大于静载重）：14D混凝土拆模强度的时间控制 混凝土结构工程施工质量验收规范(GB50204-2002)第4.3.1条规定:底模及其支架拆除时的混凝土强度应符合设计要求;当设计无具体要求时,混凝土强度应符合下表规定: 构件类型 构件跨度(m) 达到设计的混凝土立方体抗压强度标准值 (f cu
16、, k ) 的百分率(%) 板 2 50 2,8 75 8 100 梁、拱、壳 8 75 8 100 悬臂构件 100 如何科学地确定达到上述拆模强度所需的时间, 是日常施工中经常遇到的难题, 长期以来一直未得到很好解决, 这使生产进度安排、质量控制造成极大盲目性; 尽管规范要求制作同条件养护试块强度作为拆模的依据, 但目前试块的养护很不规范, 虚假因素较多。同时, 具体操作上也还存在一定的难度, 即无法具体确定送检时间。另一方面, 施工单位为了追求利润, 降低成本, 减少投入, 模板与支架数量配置往往不足, 随意拆模的现象十分普遍, 对工程质量、施工安全造成隐患。 t= t= 3.1 影响混
17、凝土强度增长的主要因素 一是混凝土成熟度M。大家知道，混凝土强度的增长是随着时间的增加而增长的，温度越高增长越快，反之，温度越低增长也就越慢。混凝土成熟度就是时间与温度对于混凝土强度增长的综合影响值, 可按下式确定: Mt (T10) (1) 式中: M- 混凝土成熟度(.d); T- 混凝土平均养护温度() t- 混凝土养护时间(d)(从终凝开始起算 ) 二是混凝土强度增长特征值A。 大家知道，同样的养护温度条件，混凝土强度的增长也各有不同，这种特性，我们用强度增长特征值A表示，A值大，早期强度高；A值小, 早期强度低，其大小与水泥、外加剂品种以及水灰比大小有关。 3.2 混凝土强度增长与成
18、熟度的关系式f t / f28 = M / (A .M + B)(2)式中: f t -某一龄期混凝土强度值; f28 -混凝土28天强度值; B与A值大小有关的常数，B=840(1-A) 3.3 混凝土达到拆模强度所需的时间 1. 混凝土达到拆模强度所需成熟度M =C.B / (1- C.A) (3) 式中: C-规范规定的混凝土拆模强度与混凝土配制强度的比值, 例如：C30混凝土达到抗压强度标准值的75%时应为22.5N/mm2, 如果混凝土配制强度按设计强度标准值的1.15%考虑，则C=22.5/ (301.15)=0.65。 以8m跨度以内的梁为例(A=0.84), 混凝土达到拆模强度
19、所需的成熟度应为192, 而跨度等于、大于8m 时, 混凝土达到拆模强度所需的成熟度M应为430。 2. 混凝土达到拆模强度所需的养护时间 t 可按下式确定: t = M / (T+10) (5)现以混凝土配置强度f0 按1.15f,cu,k,为例, 给出混凝土分别达到抗压强度标准值的75 %、100 %所需的养护时间(见下图)。 M= t= 注:1. 实线为混凝土达到抗压强度标准值的75%所需时间,虚线为混凝土达到抗强度压标准值的100%所需时间。2. 图中: A=0.82, A=0.84, A=0.86, A=0.88。 从以上分析可以看出: 一是温度越高, 混凝土所需的养护时间越短, 冬
20、季施工所需的养护时间几乎是常温季节时的2倍甚至更多；二是达到100%强度所需的养护时间几乎是75%强度所需时间的2倍甚至更多。 3.4 几点建议 1. 采用本方法预估混凝土的时间，其关键一是准确掌握各种水泥、外加剂、水灰比的A值。为此, 需要进行必要的试验, 积累一定的试验数据，建议预拌混凝土厂对日常试验资料进行统计分析，为用户提供依据; 二是认真做好施工现场气温记录 (气象预报温度与实际有一定误差, 只能作为参考)。 2采用本方法预估拆模时间，拆模前尚需对试块进行试压, 并根据试压结果确定能否拆模。 3. 冬季施工时应适当提高混凝土配制强度, 以降低混凝土拆模强度与混凝土配制强度的比值 C。
21、 4. 如拆模时混凝土强度不能满足规范要求时, 也可根据混凝土实际强度通过结构验算确定。砼浇注完毕后模板拆模时间砼浇注完毕后模板拆模时间的规范要求是什么？夏季与冬季柱、梁、板的拆模时间分别是怎样的提问补充：强度是C30或者C35的砼，它们的拆模时间是几天？提问补充：具体要几天强度达到100%才能拆模？满意答案：要看是什么混凝土构件，规范规定的一般混凝土构建的拆模时间是：每天的平均气温不低于20，15天可以拆模；但是，按照多年的施工经验，按照规范规定的时间拆模是不可能按期完工的，在正常的施工中：圈梁、构造柱的模板一般3天就拆除；现浇板、梁模板一般3天拆除侧面模板，15天拆除底面模板，但是每隔2米
22、左右打一颗点柱。框架柱一般是7天拆除模板，钢筋混凝土底模板拆除时间参考表现浇砼底模拆模所需砼强度（摘自混凝土结构工程施工质量验收规范）结构 跨度 达到设计强度标准值的百分率梁 L8m 75%L8m 100%板 L2m 50%2mL8m 75%L8m 100%悬 臂梁、板 L2m 75%L2m 100%达到拆除砼底模板所需强度的参考时间（摘自施工手册）使用425#普通水泥所需天数砼达到设计强度标准值的百分率 硬化时昼夜平均温度(摄氏度) 5度 10度 15度 20度 25度 30度50% 10 7 6 5 4 375% 22 15 12 9 8 7100% 5040 30 28 20 18使用4
23、25#矿渣水泥所需天数砼达到设计强度标准值的百分率 硬化时昼夜平均温度(摄氏度) 5度 10度 15度 20度 25度 30度50% 16 11 9 8 7 675% 32 22 16 14 13 11100% 6050 40 28 24 20模板拆除时间表拆除承重模板的估计期限表 硬化时昼夜平均温度水泥品种 水泥标号 达到设计强度 1 5 10 15 20 2530 拆 模 拆 除 期普通水泥 32.5 50% 18 12 8 6 4 3 3普通水泥 42.5 15 10 7 6 5 4 3矿渣水泥 32.5 28 22 14 10 8 7 6矿渣水泥 42.5 28 16 11 9 8 7
24、 6普通水泥 32.5 70% 28 20 14 10 8 7普通水泥 42.5 20 14 11 8 7 6矿渣水泥 32.5 32 25 17 14 12 10矿渣水泥 42.5 30 20 15 13 12 10普通水泥 32.5 100% 55 45 35 28 21 18普通水泥 42.5 50 40 30 28 20 18矿渣水泥 32.5 60 50 40 28 24 20矿渣水泥 42.5 60 50 40 28 24 20规范有规定，留置同条件养护试块。悬臂结构达到100%，跨度8米以上达到100%，2米-8米达到75%。小于2米的达到50%.拆模有几点要注意!一,对于多层现
25、浇框架,拆模要考虑上层的模板及施工荷截,底层拆模后,结构能不能承受.二,对于墙板模板,拆模应对称同时进行,不能只拆一边不拆另一边,不然,就会出现拆除后的一侧因另一边未拆除的模板支撑的水平力而导致开裂.三,拆模后的模板要及时运走不能集中堆放于楼板上.四,拆模前一定要先有现场同条件养护的砼试验报告,只有当满足了砼的拆模强度要求才能拆模,否则,不能进行混凝土结构工程施工质量验收规范（GB502042002）4.3.1规定，拆除底模和支架时的混凝土强度要求：1、板A：构件跨度不大于2米，要求达到设计的混凝土立方体抗压强度标准值的百分率应不小于50%；B：构件跨度在区间（2m，8m的，要求上述值不小于7
26、5%；C：对于构件跨度大于8米的，要求达到100%2、梁、拱、壳A：跨度不大于8米的构件 要求达到75%以上的百分率；B：跨度大于8米的构件 ，要求强度达到100%3、悬臂构件，均要求设计强拆模时间度达到100%。以上是规范，在施工中看是用什么水泥：普通硅酸盐早强型水泥在度左右的气温大概天强度基本能达到，的强度要等到天；纯硅早强水泥在以上的气温大概天可以达到；天左右强度能够增长到。混凝土侧模拆模时间一般只要保证表面及棱角不因拆模而受到损伤就可以了，一般情况下混凝土浇筑完一天后就可以拆了，从实际情况来看也是尽早拆拆模效果比较好。底模就根据GB50204-2002中的要求。一般来说在混凝土施工时现
27、场留置同条件拆模试块，在估计时间差不多时进行试压，试压达到要求后经监理同意后进行拆除（因为需要填报拆模检验批，里面有拆模强度一项，要求填的就是拆模试块强度）。按混凝土强度来确定拆模时间实际上是很难测量与控制的。现在有一种算法是跟温度相关的，就是先测量早中晚的温度，其平均值为当天的温度，当温度乘时间(按小时计)达到600度小时即为拆模的时间，可以参考一下。初凝一般两个小时左右，要看气温一般混凝土构建的拆模时间是：每天的平均气温不低于20，15天可以拆模；但是，按照多年的施工经验，按照规范规定的时间拆模是不可能按期完工的，在正常的施工中：圈梁、构造柱的模板一般3天就拆除；现浇板、梁模板一般3天拆除
28、侧面模板，15天拆除底面模板，但是每隔2米左右打一颗点柱。框架柱一般是7天拆除模板GB50204-2002：4.3 模板拆除主 控 项 目4.3.1 底模及其支架拆除时的混凝土强度应符合设计要求；当设计无具体要求时，混凝土强度应符合表4.3.1的规定。检查数量:全数检查。检验方法:检查同条件养护试件强度试验报告。表4.3.1 底模拆除时的混凝土强度要求构件类型构件跨度(m) 达到设计的混凝土立方体抗压强度标准值的百分率(%) 2 50板 2,8 75 8 100梁、拱、壳 8 75 8 100悬臂构件 1004.3.2 对后张法预应力混凝土结构构件，侧模宜在预应力张拉前拆除；底模支架的拆除应按
29、施工技术方案执行，当无具体要求时，不应在结构构件建立预应力前拆除。检查数量:全数检查。检验方法:观察。4.3.3 后浇带模板的拆除和支顶应按施工技术方案执行。检查数量:全数检查。检验方法:观察。一 般 项 目4.3.4 侧模拆除时的混凝土强度应能保证其表面及棱角不受损伤。检查数量:全数检查。检验方法:观察。4.3.5 模板拆除时，不应对楼层形成冲击荷载。拆除的模板和支架宜分散堆放并及时清运。检查数量:全数检查。检验方法:观察。Electricity lines, equipment inspections, found hidden in time for rectification, mai
30、ntenance, and security. 9, do not use an open flame in the classroom, prohibit burning stove, lit candles, mosquito repellent, no smoking, and banning messy wiring. Without using any household appliances is not allowed. 10, live on campus faculty members, must lead by example, and educate families a
31、nd children ready to fire. 11, household use of gas in schools, to master proper usage, pay attention to the leak-proof, explosion-proof, fireproof, closing valve after use to ensure security. 12, dining room must be qualified, and annual testing of pressure vessels, to regularly check, the canteen
32、workers must be certified, strictly by operation operation, gas tank and stove safety distance of 1.5 meters, to prevent accidents. 13, the adverse consequences caused by ignoring fire safety regulations, will be punished, until investigated for legal responsibility. Song Lin Xiang Liu Jia ping elem
33、entary school March 2016 Xiang Liu Jia ping elementary school, pine slopes surrounding safety management system 1 teachers and students, the surrounding area of the school governance covers personal and food hygiene, cultural events and other aspects, integrated governance shall obtain wide support
34、and full cooperation of the community. On the surrounding environment in schools should be closely monitored. 2, school work at the same time, should pay attention to the safety management of school environment, should take the initiative to contact the district police station, the village Committee
35、, Correctional Centre, Township government, business management and other departments to do a good job management. 3, teacher on duty with the exception of inspections in schools, should also pay attention to environmental inspections near the campus, found that the jobless migrants from rural areas
36、, for example, harassment of students and a variety of accidents, according to different situations reported school officials or the police station in a timely manner, to protect the safety of students. 4, every day before school, teachers remind students, pay attention to traffic safety. 5, should
37、educate students to respect social ethics, and various regulations, maintaining public order, and fight the bad guys, and grasp the correct ways and means of maintaining and improving students self-care ability. 6, the establishment of emergency rescue teams of teachers in schools, on high alert and
38、 deployed. Song Lin Xiang Liu Jia ping elementary school March 2016 song Lin Xiang Liu Jia ping primary school teachers and students organizations out of safety management system organization activities between teachers and students, to draw up a precise plan and security measures must be signed by
39、the school officials to review the programme of activities agreed upon Correctional Center agreed to implement. Organization to the field relatively far or activities require approval by the Deputy Director of the Education Bureau in charge of security. 2, each activity should have a specific respon
40、sibility, pay attention to the persons age, physical match. Route 3, activities, location, field surveys should be carried out in advance. 4, activities for the means of transport should explain the situation to the school to comply with vehicle, safety requirements, before the line for repairs. 5,
41、each activity must have security, emergency response plan for accidents. 6, picnics, hiking, picnic to pay attention to fire prevention, food poisoning, prevention of fall accidents 7, the activities near the rivers, reservoirs, no measures or do not meet the security requirements of the Organization and not let students into the water9