Special security plan [special stake plan]

The Lower Reaches of the Old Yellow River in Huai 'an City (Hull to Lianshui Stone)

Lake section) treatment project construction Ⅰ bid section

wood

stake

carry out

worker

square

situation

Approve: approve: prepare:

Jiangsu Huaiyin water conservancy construction co., ltd

Huaian Yellow River Old Course Ganhe Lower Section Governance Bid 1 Projects Department

1 project overview

1. 1 Overview

(1) Nanchang Road-An Lan Section, Qinghe District

The revetment section is 5.34km long and located on the right bank of the old Yellow River, with the pile number of 16+289 ~ 2 1+629. After deducting the existing vertical retaining wall revetment, wharf, Yao Fei Road Bridge and S327 Provincial Highway Bridge on both sides of Ninglian Road Yellow River Bridge, the total length of newly built revetment is 5.0 18km.

The protection type of this road section is wood pile combined with plant slope protection. The elevation of pile revetment top is 8.8m；; The pile length is 4.0 ~11.0m. The diameter of the small head with a pile length of less than 9m shall not be less than 16cm, and the diameter of the small head with a pile length of more than 9m (inclusive) shall not be less than 22cm. C20 concrete foundation of 0.4×0.4m is set at the rear side of the pile, on which the wood-like railing with the height of 1.2m is set. In order to improve the overall stability of the pile, a flat iron is set at a distance of 15cm from the pile top, which is connected with the pile body by bolts, and an open bolt is welded every 30cm to connect with the concrete foundation.

Pile numbers of slope protection are 16+289 ~ 16+660,18+210 ~18+920. The width of the platform at the top of the pile is 5m, and the concrete frame is used for slope protection from the platform to the flood control level 10.60. The slope ratio of the slope protection is 1:4.0, the elevation of the top of the concrete frame is10.60m, the frame is a 2.0m× 2.0m grid, and the grid skeleton is staggered with 0.2m× 0.2m concrete ridges, and Bermuda grass is laid in the frame. The intercepting ditch has a clear width of 40 cm, a clear depth of 30 cm and a wall thickness of 12 cm. Set a intercepting ditch every 100 m and a intercepting ditch every 100 m. ..

The pile number is 20+050 ~ 2 1+629, and bermudagrass is used for slope protection. The platform at the top of the pile is 5m wide, bermudagrass is laid on the top of the dike, and the elevation of the dike top is 8.80-13.80m; Concrete intercepting ditches are set at the top and bottom of the slope protection. The intercepting ditch has a clear width of 40 cm, a clear depth of 30 cm and a wall thickness of 12 cm. Set a intercepting ditch every10m, and set a horizontal intercepting ditch every100m. ..

Piles are used for revetment, and the pile numbers are16+881~18+210 and 18+920 ~ 20+050. The platform at the top of the pile is 5m wide, and concrete intercepting ditch is set behind the platform. The intercepting ditch has a clear width of 40 cm, a clear depth of 30 cm and a wall thickness of 12 cm. Set a intercepting ditch every 100 m and a intercepting ditch every 100 m. ..

(2) East section of An Lan Road, Development Zone.

The revetment is 4.776km long and located on the right bank of the old Yellow River, with pile numbers of 2 1+629 ~ 25+500 and 26+703 ~ 27+608. After deducting the length of S237 provincial highway bridge and G2 expressway bridge, the newly-built revetment is 4.716km long. Among them, the section with pile number 25+500 ~ 26+703 is located in the golf course, and the current greening environment is good, and the bank protection treatment has been carried out, so this section is no longer included in the renovation scope.

The protection type of this road section is wood pile combined with plant slope protection. The elevation of pile revetment top is 8.8m；; The bottom elevation is determined according to the calculation of pile stability. The pile length is 4.0 ~10.0m. The diameter of the small head with a pile length of less than 9m is not less than 16cm, and the diameter of the small head with a pile length of more than 9m (inclusive) is not less than 22cm. C20 concrete foundation of 0.4×0.4m is set at the rear side of the pile, on which the wood-like railing with the height of 1.2m is set. In order to improve the overall stability of the pile, a flat iron is set at a distance of 15cm from the pile top, which is connected with the pile body by bolts, and an open bolt is welded every 30cm to connect with the concrete foundation.

The platform at the top of the pile is 3.0m wide, and a intercepting ditch is set behind the platform. The intercepting ditch has a clear width of 40 cm, a clear depth of 30 cm, and a wall thickness of 12 cm. A seam is set every 10 m, and a horizontal intercepting ditch is set every 100 m..

The main work during this construction period is the setting of wooden stakes.

1.2, main quantities

The number of wooden stakes in this building is about 48,762.

1.3, general situation of surrounding environment

The surrounding main structure is built close to the river bank, and the impact of piling on the surrounding environment can generally be ignored, but according to the actual situation on site, the construction safety and construction during piling are mainly considered.

When the work is inconvenient, the monitoring of the river bank should be strengthened during the construction process, and the construction should be stopped and handled in time if any abnormal situation is found.

1.4, composition and characteristics of foundation soil

According to the field logging data of borehole and indoor geotechnical test results, combined with the detailed exploration stage and the engineering geological data of nearby sites, according to the soil characteristics, burial distribution conditions and physical and mechanical properties of foundation soil, and according to the soil layer within the borehole depth, the foundation soil within the site investigation depth can be divided into five engineering geological layers, which are described in detail as follows:

Layer 1: prime fill (Q4ml). Mainly sandy loam or silty sand. Layer thickness is 0.6 ~ 8.3m Layer 2: sandy loam or silty sand (Q4al). Slightly to moderately dense. Layer thickness is 2.2 ~ 9.7m Layer 2- 1: loam (Q4al). Plastic. The layer thickness is 3.3m

The third layer: clay (Q4al). Plastic ~ hard plastic. Layer thickness1.7 ~ 3.4m. ..

Layer 4: sandy loam or silty sand, loam (Q4al) locally. Medium density ~ dense. Layer thickness 0.9 ~

4.9 meters.

5 layers: clay or loam. According to its lithology and strength, it is divided into two sub-layers:

Layer 5- 1: clay mixed with sandy loam (Q4al). Clay is fluid plastic ~ soft plastic. Sandy loam is slightly to moderately dense. The layer thickness is 5.0m

Layer 5-2: loam or clay (Q4al). Plastic ~ hard plastic.

2. Construction machinery

Vibrating hammer (commonly known as "manipulator") is selected for piling, which has the characteristics of reasonable structure, large impact capacity and high working efficiency. When the vibrating hammer is used to pile, the sand layer will be vibrated, and the mechanical properties will be obviously reduced, which can effectively reduce the pile driving resistance. Vibrating hammer piling is shown in the following figure:

Among them, the pile number is 24+385 ~ 24+74 1, and the piling length is10m. Considering the pile length and geological structure, the pile driver ship (diesel hammer) is adopted in this section.

3. Building technology

3. 1, timber procurement and storage

Timber piles are mainly purchased through the northeast timber market and transported to the construction site by car; Pay attention to the quality of wood when buying wooden stakes, and the pile length should be slightly longer than the design pile length. The material of the pile of wood used must be uniform, and there must be no excessive bending. When both ends of the stake are connected in a straight line, the deviation between the center of each section and the straight line shall not exceed the relevant provisions; In addition, there shall be no holes, cracks or other defects that may damage the strength.

During lifting, loading, unloading and stacking of wooden stakes, the pile body shall not be impacted or vibrated to avoid damage to the pile body. When using wooden stakes, they should be used in the order of arrival at the construction site, and at the same time, check whether the wooden stakes are complete. The storage foundation shall be solid and flat, and shall not sink to avoid pile deformation.

3.2, piling process

When piling, each process shall be carried out continuously, and the process flow is as shown in the following figure:

Pile driving flow chart

3.3, piling construction method

Baseline measurement 3.4. 1

Before piling construction, recheck the survey control baseline and baseline points on site, measure the construction plane coordinate control points and elevation reference points according to the site conditions, and release the piling construction baseline.

3.4.2, site leveling

Level and compact the riverbank site. According to the actual situation, the subgrade is soft, so gravel cushion should be laid and compacted to ensure the safety of the pile unloading crane and construction machinery. According to the situation, the road floor should be laid on it. The vertical height between the river bank and the water surface should not exceed 1m, the pile position should be about 2-5m away from the river bank, and the width of the temporary road on the river bank site should not be less than 3m, which is convenient for machinery and workers to construct.

3.4.3, pile positioning

In order to control the axial position of the pile wall, reduce the plane deformation of the pile and improve the piling efficiency. Machining guide frame with sufficient strength and rigidity.

pile

In order to make the pile connection close, piling is the most critical process. Therefore, vibration hammer and walking are adopted.

In order to make the pile compact, the pile driver works in one direction in sequence.

Pile driving is driven by single pile, and guide frame is set according to the direction before pile sinking. The guide frame is made of I-beam as the guide device for piling. Piling is mainly based on elevation control.

Strengthen the observation of piling construction process, record the abnormal phenomena in construction, find out the causes of abnormal phenomena and take corresponding effective measures. After piling is completed, the pile should be clamped in time to make the pile foundation form a whole, and the piling deviation should be measured. The piling process shall be carried out in strict accordance with the specification requirements, and the piling construction quality shall be well controlled. Choosing sequential operation and relatively convenient operation conditions is beneficial to control the degree of combination between piles.

3.5, piling quality control

In the process of construction, we use theodolite to strictly control the verticality and plane position of the pile, and sink the positioning pile to the design elevation as required to ensure the stability of the positioning pile. After driving the positioning piles, we will drive the next pile one by one to the design elevation. The alignment of each pile has a great influence on the normal piling of subsequent piles. During piling, careful control should be taken to ensure piling quality. Specific quality control measures are as follows:

3.5. 1. Before piling, ensure that the external dimensions, soaking time and soaking length of the pile meet the design and specification requirements;

Axis control

Before piling, the axis of the system should be compounded, and the axis deviation of the pile should be controlled within 10cm. Check and adjust the pile clamping device to ensure that the pile axis meets the requirements.

3.5.3, verticality control

Correcting and monitoring pile verticality with theodolite. The allowable deviation of pile verticality is controlled within 65438 0%. During the period from the start of piling to 2m above the ground, if any deviation is found, it shall be stopped and adjusted in time. If possible, it shall be

Pull out the pile, remove obstacles and backfill before piling. When the pile body is seriously inclined, the pile should be pulled out, positioned with steel piles, and then sank again.

3.5.4 Elevation control

When the pile tip is located in soft soil, the pile tip is required to reach the design elevation, and the allowable deviation of the pile top elevation should be controlled within 50 mm When piling approaches the specified elevation, the parameters of vibration hammer should be adjusted, and the frequency and intensity of vibration should be controlled to ensure that the elevation of pile top meets the design requirements.

3.5.5, piling allowable deviation

The allowable deviation of piling is as follows:

Axis allowable deviation is10mm; ;

The allowable deviation of pile tip elevation is 50mm；;

The allowable deviation of the clearance between piles is 50 mm.

The allowable deviation of verticality is 65438 0%.

4, construction guarantee measures

4. 1, safety assurance measures

The construction of peace is a major event related to personal health, family happiness, social stability and national prosperity. Strengthening the publicity and education of safety knowledge, improving the safety technical quality of construction personnel, strengthening on-site safety management and strengthening safety precautions are several important components of building safety work.

1, security target

The safety goal of this project is to be safe and accident-free during the whole project construction.

2, safety organization measures

2. 1, the full-time safety officer is fully responsible for the safety work during construction, specifically responsible for inspection and supervision, and establishes the on-site safety production guarantee system.

2.2, adhere to the safety technical disclosure meeting system before construction and safety education system before construction.

Degree, clear the safety objectives of this project, and implement the safety responsibilities of each post.

2.3. Hold regular safety work meetings to summarize and arrange safety work.

2.4. Carry out safety activities, arrange safety slogans and banners at the construction site, and actively carry out safety knowledge publicity and education.

2.5, seriously implement the safety regulations and operating requirements, construction personnel must wear safety helmets, it is forbidden to illegal operation, put an end to all kinds of accidents.

2.6, resolutely deal with all kinds of safety violations, rectification within a time limit.

2.7, completes the daily production safety records, and fill in the safety diary.

3. Traffic measures

3. 1. When the on-site material transport vehicles enter and leave the construction site, the entrances and exits should be commanded by special personnel to avoid traffic accidents.

3.2, the construction site, especially around the material entrance, should leave a relatively large space, in order to facilitate the material transport vehicles turn, turn around, in and out.

3.3. After the transport vehicles enter the site, they must first observe the route, remove items that will affect the traffic, and at the same time lay subgrade steel plates on the soft subgrade pavement to ensure smooth flow.