In the construction of highway projects, soft soil foundation problems are often encountered, which requires good soft foundation treatment work. Subgrade replacement and filling construction is an important method of soft foundation construction. The following is the roadbed replacement and filling construction log that I compiled. Let’s take a look at this kind of work. Roadbed replacement and filling construction log 1
With the rapid development of our country's economy, the number of means of transportation has increased, and the roads have become more and more crowded, which has brought great inconvenience to people's lives and work. In order to relieve traffic pressure, Attention must be paid to the quality of road construction. During the roadbed replacement and filling construction, safe construction must be carried out and the principle of "safety first" must be adhered to. First of all, the general layout of the construction site should be done before construction. Obvious safety signs should be set up at the construction site and no unauthorized removal is allowed. Furthermore, a certain safe space should be left to keep the roads open and fences should be set up around the site to isolate it from the outside world. protect. During construction, the safety awareness of workers should be improved to reduce the occurrence of traffic accidents so that the roadbed replacement and filling work can be carried out safely and smoothly.
Because the road engineering route is long, and the project volume and work intensity are large, mechanized construction is applied to highway subgrade filling and replacement construction. It can effectively improve work efficiency and obtain good economic benefits. Mechanized construction refers to the use of mechanical equipment to replace people in engineering construction operations to complete construction operations in arduous, heavy, and harsh environments. In road replacement and filling construction, it is very important to make scientific choices and rationally configure mechanical equipment for construction based on relevant conditions such as project content and geographical location. Without scientific organizational management and reasonable allocation and combination, even with a high degree of mechanization, construction speed and maximum economic benefits cannot be guaranteed. During the construction process, some narrow roads will be encountered and large equipment cannot operate. At this time, some small equipment should be used to complete the work, which can achieve the purpose of saving time, effort, and cost.
Technical clarification work should be carried out before construction, and the design intentions and requirements need to be clarified. At the same time, check the silt depth in detail in the early stage of construction to provide timely guidance for on-site construction. After construction materials arrive at the site, quality inspection must be carried out to ensure that all performance indicators are in compliance with construction regulations. If the materials are unqualified, they shall not be used. According to construction regulations, filling and rolling must be carried out in layers, and the thickness of each layer of loose paving must be controlled within a reasonable range. When using side station supervision to conduct full-process quality supervision, it is necessary to strictly control the silt excavation depth, compaction degree, etc., and make relevant records. For example, everything that occurs during construction must be reflected in the original records. Construction procedures that do not meet the requirements must be noted, and relevant measures and remedial methods must be taken. This requires that construction regulations must be strictly followed and construction techniques standardized. Roadbed replacement and filling construction log 2
There is a fish pond in the filling section K085~K155 of the north section of Anhe West Road, and a large amount of sewage flows into the fish pond from the residential area on the right side of the road. After the construction unit , the design unit, supervision unit, and construction unit conducted on-site surveys. The silt layer in this section was 5-6 meters thick. The soft foundation of this section was treated by removing the silt and replacing it with blocks (chips).
The roadbed construction of this section will be completed in October 20XX. Before construction, the fish ponds must be drained. Drainage shall be carried out by means of drainage ditches. The water in the fish ponds shall be discharged outside the roadbed construction scope. For sewage in residential areas, a pit shall be dug on the right side of the K155 road. Then a 4KW sewage pump is used to pump the sewage to the open space outside the line. After the dredging and filling are completed, a Φ400 pipe and three Φ700 brick inspection wells are added to the right side of the road to introduce the sewage into the sewage pipe of Zhongxiu Long Street.
(1) Dredging
After the fish pond is drained, measure the original ground elevation and process the area.
Before dredging, use an excavator to mix the silt in the fish pond with the soil in the excavation section K155-160, then excavate it and transport it to the designated location. After the dredging is completed, measure the base elevation after dredging to determine the dredging volume.
(2) Replacement and filling
1. Construction preparation
The scope and depth of replacement and filling should be verified before construction. When mechanical excavation and replacement are used, , a protective layer of 30 to 50cm should be reserved for manual cleaning.
Prepare a foundation replacement and filling construction plan, and provide technical explanations to the operators after approval.
Collect site engineering geological data and hydrogeological data.
Before construction, parameters such as the control range of filler moisture content, paving thickness, and number of rolling passes should be reasonably determined.
2. Measurement and setting out
According to the actual situation on site, set out the characteristic points of the soft foundation treatment area (starting point, end point number, width on both sides), and review the treatment area and the original ground surface elevation. Excavation can only begin after the floor plan has been drawn and approved by the supervising engineer.
3. Base cleaning
(1) Floating soil, accumulated water and mud in the pit should be removed before construction. The slope of the foundation pit must be stable to prevent landslides.
(2) When excavating the soft soil layer within a certain depth under the foundation, the original soil layer at the bottom of the pit should be avoided from being disturbed. For this reason, a 300-500mm thick soil layer can be left unexcavated for the time being. Before laying and replacing the fill, dig to the replacement elevation. Collapse of soil on the slope of the foundation pit should be prevented from mixing into the filling layer.
4. Foundation pit inspection
Check whether the foundation pit excavation meets the requirements, whether the foundation bearing capacity meets the design requirements, and whether the foundation pit excavation size meets the construction requirements.
5. Inspection of replacement materials
The treatment method for the soft foundation roadbed in this contract section is to replace the blocks (flakes) with stones. The blocks (flakes) are purchased from outside, and the maximum particle size is not If the stone is larger than 50cm, the strength of the stone (piece) must meet the design or specification requirements.
6. Layer-by-layer paving and replacement of filler
(1) The base surface of the backfill material should be laid at the same elevation. If the depth is different, the base soil surface should be dug into steps or When overlapping slopes, the overlapping joints should be compacted, and construction should be carried out in the order of deep first and then shallow.
(2) When filling in sections, the joints of each layer should be made into a slope shape, and the joints should not be in important parts such as foundations and corners.
7. Layered compaction
(1) In order to ensure the uniformity and compactness of the replacement material, smaller stones should be used before rolling with the heavy-duty rolling machine. Fill the leveled surface.
(2) Control the speed of the rolling machine. After 2 times of static pressure, use strong vibration 6 to 8 times.
(3) When the replacement material is too dry, water should be sprinkled to ensure that the upper and lower materials are well combined.
(4) Compaction should be done first around the four sides and then in the middle.
8. Leveling acceptance
(1) After the last layer of rolling is completed, the elevation and flatness should be checked.
(2) Filling should be replenished in low-lying areas in time.