What is the height of the broken pile head when drilling the pile foundation? Are there any specifications?

What is the height of the broken pile head when drilling the pile foundation? Are there any specifications? The pile head of punching cast-in-place pile is 500mm higher than the drawing. The design, structure, construction, quality and acceptance of punched cast-in-place piles are all included in JGJ94-2008 Technical Specification for Building Pile Foundation. Bored cast-in-place pile needs to chisel the pile head.

What is the standard length of the broken head of bored pile? Not less than 50 cm, subject to the removal of loose concrete.

When pouring cast-in-place piles, the elevation of the pile top of cast-in-place piles should be 0.5~ 1.0m higher than the design elevation of the pile top to ensure the strength of the concrete at the pile head. However, the part of the pile head that is higher than the design elevation of the pile top must be chiseled away in the subsequent construction process, and the work of chiseling away the concrete of the pile head is called "breaking the pile head".

Broken pile leaders:

1, in the process of vibrating concrete, the cement slurry flows back upwards, and the strength of pile head is difficult to guarantee;

2. The main reinforcement in the driven pile is used as the reinforcement of the bearing platform;

3. In addition, in the process of concrete pouring, the pile head will inevitably fall into impurities such as soil. Therefore, it is stipulated in the specification that the elevation of the pile head is 500mm higher than the design elevation during concrete pile construction, and this part of the pile head shall be removed manually to ensure the strength of the pile body.

4. Prevent the influence of concrete necking caused by lateral force of soil on pile diameter.

After the pile head of bridge pile foundation is broken, the pile top should extend out of the bottom of tie beam. JGJ94-2008 "Technical Specification for Building Pile Foundation" stipulates that the pile top should be embedded in the cap with a diameter of 50 mm < 800 (pile with a diameter of 100 mm ≧ 800).

After the pile head of bridge pile foundation is broken, the pile top extends into the cap 10cm, but generally there is no cap with tie beam at the top of the pile, and the upper part of the pile foundation is directly a column; The top elevation of tie beam is the same as that of pile foundation, and it is connected with pile foundation.

After the pile head of bridge pile foundation is broken, the pile top should extend into the bottom of tie beam. The specification stipulates that it must be over-poured, because the aggregate of pile body concrete has gone down after vibrating, and the rest is laitance, which can not meet the load-bearing requirements and must be chiseled, so it must be chiseled after over-pouring. Generally 50-80cm.

Cast-in-place pile system refers to the pile formed by mechanical drilling, steel pipe extrusion or manual excavation in foundation soil, and placing steel cages and pouring concrete in it. According to the different hole-forming methods, cast-in-place piles can be divided into immersed cast-in-place piles, bored cast-in-place piles and dug cast-in-place piles. Bored cast-in-place pile is a kind of pile type defined by pile forming method.

Why does the bored pile of bridge break the pile head? Generally, the top of 0.5m~ 1m pile is dominated by scum and laitance, with little aggregate and insufficient strength. This is an inevitable problem when using cast-in-place pile construction technology, so the elevation of pile foundation is about 0.5m higher than the bottom of pile cap. After the pile head is broken, the reinforcement of the pile foundation extends into the pile cap.

The main reinforcement of civil pile head φ 12 bored pile head generally extends into the pile cap as designed. 10cm and 700 bar anchorage length.

Pile cap is the connecting part between pile and column or pier. Pile caps connect several or even a dozen piles together to form a pile foundation. Pile caps are divided into high pile caps and low pile caps: low pile caps are generally buried in the soil or partially buried in the soil, and high pile caps are generally exposed to the ground or water. Because the high pile cap has a free length, there is no supporting body around it to bear the horizontal external force. The stress of foundation pile is extremely unfavorable. Under the same horizontal external force, the internal force and displacement of the pile are larger than those of the low pile cap, so its stability is worse than that of the low pile cap. High pile caps are generally used in ports, docks, marine engineering and bridge engineering. Low pile caps are generally used in industrial and civil buildings. Generally, the pile head extends into the pile cap by 0. 1m, and the steel bar is anchored into the pile cap. Columns or piers are built on pile caps to form a complete force transmission system.

How to control the height of the bored pile head only needs to measure it into the hole with measuring rope or steel bar.

What should I pay attention to when the pile head is broken? 1, pile top elevation control, can't break more, the pile generally extends into the cap 10cm, and it is very troublesome to break more piles;

2. Don't bend the pile reinforcement excessively, otherwise it will be easy to break when straightening, and the reinforcement will be troublesome.

For many days, the human body in Fujian and Guangdong is relatively thin, so we pay special attention to the stability and flexibility of footwork, and there are many twisting movements (such as riding a dragon step, turning a step, covering a step, etc.). ) so that the body can rotate flexibly. Nanquan's upper limb movements are intensive, rapid and varied. Sometimes the lower limbs are still, and the fist palm can hit several times continuously to win quickly and intensively. When exerting strength, Nanquan mostly needs to shout, exhale and urge the force to increase the explosive force. Southerners have short limbs, pay attention to close combat, and have many short fists, giving full play to the advantage of "one inch short and one inch dangerous". There are many pictographic boxing in Nanquan, including common pictographic boxing such as dragon, tiger, leopard, elephant, crane, snake, horse, monkey and chicken, as well as rare boxing such as lion, tiger, fish and dog. Its number of pictographic boxing ranks first in all major boxing departments in China. The overall style of Nanquan is steady pace, firm fist strength, strong momentum, less jumping, short fist, good at waving, and enhancing strength with sound and qi. Strong and quick, dexterous and dense, combining rigidity with softness, the upper limbs and hand shapes are particularly rich. It is not as vigorous and simple as Shaolin boxing, but it is strong and powerful, but it is unique. The formation time of Nanquan boxing system is probably from the early Qing Dynasty to the middle Qing Dynasty, that is, from the end of 17 to the end of 18. It includes hundreds of kinds of boxing, widely spread in Fujian, Guangdong, Hubei, Hunan, Taiwan Province and other provinces and Hong Kong and Macao, and spread overseas very early, taking root in Southeast Asia, America and Oceania. When it comes to the contribution of spreading Chinese Wushu, Nanquan is second to none. There are many kinds of Nanquan, such as Wing Chun and Cai Lifo in Guangdong, Shaolin Qiaoshou, Wuzu Boxing, He Quan and Luohan Boxing in Fujian, Zhou Jia Boxing, Dragon Slayer Boxing and Xiaoce Boxing in Guangxi and Hongjia Boxing in Zhejiang. Black tiger fist, diamond fist. Hong Men Boxing, Yumen Boxing, Confucius Boxing in Hubei, Wu Jia Boxing, Hongjia Boxing and Xue Jia Boxing in Hunan. The representative of Nanquan, a famous school, is Guangdong Nanquan, and the representative of Guangdong Nanquan is the "Five Famous Masters". They are: 1. Hongquan. Hongquan originated from Shaolin Temple and is said to have been created by Hong Xiguan. Hong Xiguan was originally a tea merchant in Zhangzhou, Fujian, and was introduced to the five ancestors of South Shaolin Hong Men. Hongquan was later introduced to Guangdong, including five elements boxing (Golden Boxing, Wooden Boxing, Water Wave Boxing, Rocket Boxing and Land Boxing) and Ten Fists (Dragon Boxing, Snake Boxing, Tiger Boxing, Leopard Boxing, Crane Boxing, Lion Boxing, Elephant Boxing and Horse Boxing). Tieqiaosan, Lin Fucheng, Huang Tai, Huang Feihong, Lin Shirong, etc. It is the largest school in Nanquan. Second, Liu Quan. It is said that it was created by Liu Sanyan, and it was also said that it was created by Liu Sheng or Liu Qingshan in the last four schools and spread in Leizhou Peninsula. Third, all wealth. It was created by Cai Boda and Cai Jiuyi, monks of Fu Shaolin Temple in Fujian, and later spread to Zhongshan and other places in Guangdong, including Cross Boxing, Tian, Xiaoyuntian, Yan, Liu Suimei, Two Instruments and Four Elephants Boxing and so on. Fourth, Li Quan. According to legend, it was created by Li Sekai, a monk from Southern Shaolin Temple in Fujian, and taught by Li Youshan, a native of Xinhui, Guangdong. First of all, it was created by Li in Huizhou, Guangdong. James Li is popular in Zhongshan, Heyuan, Gaozhou, Longchuan and Guangzhou. Fifth, don't punch. According to legend, it was created by Zen master Shan Zhi of South Shaolin, Fujian; It is said that it was created by Mo Moshi and later spread to Mo Qingjiao. Spread in the Pearl River Delta. Most of the five famous fists come from South Shaolin, Fujian. There are some connections with the Hong Men Heaven and Earth Society. The Hong Men Heaven and Earth Society is not only a martial arts school, but also an extremely active Jianghu school. In addition to the five famous fists, Guangdong Nanquan also includes Cai Lifo Boxing (founded by Sean, a Xinhui, who studied under Chen Yuanhu, Li Youshan and Cai Fu, a monk of Shaolin Temple, and gathered the essence of Cai Jiaquan, Li Jiaquan and Buddhism Boxing, hence the name Cai Lifo Boxing), Tiger and Crane Fists (created by Lin Shirong, a Nanhai native, who combined Hong Boxing and Buddhism Boxing into one creation, also known as "Hong Tou Fowei") and Wing Chun Boxing. Nanquan has formed a unique southern feature in the coastal areas of Guangdong and Fujian. Especially since the Qing Dynasty, it has played an important role in martial arts legendary novels and movies. For example, South Shaolin in Fujian Province is said to be an anti-Qing stronghold, where Hong Men's children and chivalrous men gathered in three mountains and five mountains. Qing soldiers burned South Shaolin, and Hong Xiguan came to Guangzhou, lived in seclusion in the Big Buddha Temple, and opened a martial arts school with a monk. Another example is Fang Shiyu (the first person is Hong Xiguan), the No.2 figure in Guangdong's "Ten Tigers of Shaolin", whose mother Miao Cuihua is the daughter of Miao Xian in the "Five Old Shaolin" and is known as "a generation of women". Fang Shiyu became the hero of many chivalrous cultural works, such as Shaolin Little Hero, Evergreen Tree, Fang Shiyu's Three Visits to Wudang Mountain and Qianlong's Xiajiangnan. In the late Qing Dynasty, there appeared "Ten Tigers in Guangdong" in Nanquan, among which Su of Tieqiao III and V was also the hero of many chivalrous cultural works. Basic skills, basic skills, Nanquan, there are many kinds and schools, each with its own characteristics. Their general techniques are as follows. (1) stable horse and hard bridge: Nanquan pays attention to tying horses. Zama is a "pile step"; "Horse stance just look" pile is the foundation of Nanquan. There are big horses, ponies and half horses. No matter what form of extreme step, you need five toes to take root, emphasizing "as steady as an iron tower _ sitting like a mountain" and "hands are copper hammers, feet are horses". Once you train a horse, your legs will be heavy, your gait will be stable, and your exercise will be disciplined. The bridge is the carrier of the arm and is called the "bridge hand". For example, the arm droops and does internal rotation, which is called "rolling bridge"; Elbow sinking is called "sinking bridge". For the bridge hand, it is required that the elbow arm is rigid and the strength is stored in it. "Only by practicing hard bridge and hard horse can we play steadily and steadily." Nanquan attaches great importance to the stability of pile step and the hardness of elbow bridge hand. (2) Over-the-shoulder scapula: Nanquan posture pays attention to over-the-shoulder scapula. Taking off the shoulders means that the shoulders sink consciously, as if degassing downward. The mass scapula is to make the scapula move forward slightly to form a lump. Off-shoulder sinking can strengthen the elbow. The front of the scapula can tighten the back and contribute to the deficiency of the chest. (3) Straight and round chest: Nanquan posture also pays attention to straight and round chest. Straight neck means that the chin retracts to make the neck straight, but not stiff. Round chest, chest slightly culvert, slightly round. A straight neck helps to combine the strength of the chest, back, shoulders and elbows, while a round chest helps to sink the qi and strengthen the abdomen. (4) Kidney-qi strengthening abdomen: Nanquan also attaches great importance to kidney-qi strengthening abdomen, emphasizing kidney-qi strengthening abdomen and tightening abdominal muscles. Sinking air and strengthening the abdomen will make the buttocks converge. It's related to the scapula. Straight neck, round chest and five-toed grip are a whole, and the upper and lower parts can be integrated, and the strength of the whole body will be condensed into one place. (5) Five in One and Three Promotions: Five in One means hand and eyes closed, eyes closed at will, shoulders closed with waist, body closed with step, up and down closed. The three reminders are: hand reminder, step reminder and body reminder. Generally speaking, when you start to punch, your body should turn around, punch at your waist, tuck in your abdomen, and then send it. The technique must be flexible, the footwork must take root, "if the technique is fast, the horse will be born, and if the horse is not chaotic, there will be rules", and the technique and footwork must also be coordinated. When doing Nanquan, you should "stretch your hands, eyes, body and feet", move your eyes at will, convey your mind with your eyes, and signal with your hands. It needs the coordination of hand, eye, body, posture and heart strength, so that Nanquan can be integrated and achieved in one go. (6) the force comes from the waist; "Hands come from the chest and strength comes from the waist." Nanquan regards the waist as an important hub of strength, and strength is driven by the waist. At the same time, Nanquan also emphasizes that waist skills must be combined with rigidity and softness, such as "fish swim in water and snakes swim on land". If the waist is stiff and lacks flexibility, it will also lead to poor strength. Nanquan is measured by strength (short strength), long strength, drifting strength, persistence and explosive power. These strengths must be "in the legs, slaughtered in the waist, and shaped in the hands." (7) Vocal yelling: Nanquan pays attention to vocal yelling. Generally, there are six sounds, such as Xi, Drink, Wow, Ew and Ho. Use different cheers with the change of boxing potential. "When you shout, the clouds will change color. When you make a fist, the mountain will collapse." You shout to cheer, to help your strength, and to help your image. Don't shout. (8) Strong body and thick body: Nanquan also emphasizes luck, muscle uplift, tension and relaxation, and the whole body is strong and sturdy, which makes the whole fist posture show a strong image. Wing Chun Boxing, the representative of Nanquan, is one of the boxing styles in southern China, which was popular in Guangdong and Fujian in its early years. This fist was first introduced to Yongchun County, Fujian Province, and was created by Yan Sanniang of the county. It was named after the place name, so some people named it "Wing Chun Boxing" after Yan. The main hand types of this boxing are Yan Feng Boxing and Liu Ye Palm, and there are three sets of boxing routines, namely, mindfulness, bridge-seeking and fingering. The basic skills are mainly three hands, as well as falling hands, lifting hands, breaking hands, sinking bridges and blocking positions. The main steps are Siping Horse, Sanzi Horse, Chasing Horse, Kneeling Horse and Independent Step. It is a combination of internal boxing and melee boxing. Based on actual combat, it is characterized by changeable moves, flexible use, flexible punching, short bridge and narrow horse, and being good at exerting strength. It uses techniques such as big flashing edge, small throwing, ploughing and hugging arms, touching, remembering feelings and bending hands in the middle to build, cut, sink, mark, arm, wrist, finger, stick, touch, iron, steal and steal. With the help of the sensitive feeling of the hand bridge skin, play an inch-strong internal boxing. Kirin step Kirin step: the front legs are arched, the rear legs are knee-deep, the calves are bent, the rear toes are exerted, and the heels are suspended.