CN110847220A

CN110847220A - Method for replacing column by stealing foot of concrete retaining wall

Info

Publication number: CN110847220A
Application number: CN201911050207.9A
Authority: CN
Inventors: 不公告发明人
Original assignee: Chongqing Fat Technology Development Co Ltd
Current assignee: Chongqing Fat Technology Development Co Ltd
Priority date: 2019-10-21
Filing date: 2019-10-21
Publication date: 2020-02-28

Abstract

A method for changing posts by stealing feet of a concrete retaining wall is a method for changing the posts and the retaining wall by stealing the original soil under the feet of the concrete retaining wall under the condition that the height of the concrete retaining wall under the feet is increased without dismantling the original retaining wall on the upper side; is a method of gradually exchanging for two or three times. A simple method which can save a large amount of raw materials and working hours; firstly, the polder soil outside the retaining wall is not dug, but a shaft which is dug 1/3 just below the original retaining wall is used as a pile shaft, a concrete pile is replaced to a position below the horizon to be lowered to prop against the upper retaining wall, then the polder soil which needs to be lowered is dug, then the soil below the foot of the remaining 2/3 retaining wall is replaced, and then the remaining 2/3 retaining wall is replaced. The method is simple, labor-saving, material-saving, time-saving and more money-saving.

Description

Method for replacing column by stealing foot of concrete retaining wall

The first, the field: in modern building engineering, the concrete fort bank with a very high upper part is often built firstly, and then the construction and the construction are carried out at the outer side due to the construction requirement, and because the places are quite tight, the very high retaining wall root has to be forced, for example: a Zhongnan oil filling station No. 248 of Chongqing city Feng jishi city is characterized in that the filling station is moved inwards due to road improvement, the original foot of a fort with the width of more than 5 meters has to be forced together, the outer filling station is just barely wide, but the foot of the fort at the inner side has the height of more than 8 meters, and the foot of the fort at the inner side has the height of more than 10 meters, and then the foot protecting soil is dug flat on the outer foundation and then dug down for two or three meters for oil drainage and irrigation, so that the height of 20 meters is nearly reached in total, however, the foot of the original fort is not a rock, but loose soil stone, and under the condition, the loose soil is partially changed into a concrete pile column, and partially changed into a concrete retaining wall. The original concrete retaining wall foot is firmly supported, the original fort is not sunk and expanded a little, and about 5 meters of loosening soil and stones are exposed under the foot of the original fort, so that the condition is that much more and more soil and stones are exposed. The foot stealing and pole changing method can be used.

Secondly, background of the prior art: the polder except the original fort is excavated in the society at present, and concrete piles are driven outside the original fort and close to the original fort above the original fort. According to the construction, 1.5 m square concrete piles are driven every 3-4 m beside the original fort, the piles are not driven under the fort, but are driven close to the fort, and loose soil between the piles is shielded by a concrete retaining wall with the thickness of about 30 cm. However, a foundation pit oil drainage tank is dug downwards immediately outside the pile foundation or other operations are carried out; because the concrete piles driven by the concrete piles do not directly and firmly support the foundation feet of the retaining wall fort above the original, in the construction process, cracks are inevitably expanded outwards due to the strong sinking pressure of the old fort above the original, the crack is already up to more than 6-8 cm, and the concrete piles may continue to sink or expand outwards. Because the original fort is provided with the drainage ditch, if heavy rain occurs in the sky, water can be poured into the seams, and the seams are possibly dangerous. Because the water in the ditch is irrigated to dilute and wet the loose soil under the original retaining wall foot, the ditch cannot bear huge pressure above the ditch, and the ditch must sink. The newly driven concrete pile is turned over. The invention not only can solve the danger that the old fort does not sink and stabilize the old fort, but also can reduce the occupation of the concrete foundation outside the old fort with the width of 1.5 meters, and is almost the same as the outer surface of the old fort, and only a little more than the old fort is arranged on an upward slope, so that the pile and the retaining wall have the potential of being leaned against by a chair and are tighter and tighter, and are not externally stretched. The invention relates to a method for replacing a column by a beam, which is a successor for replacing a displaced member in the industry of replacing the column by the beam and replacing the column by the beam in the whole life and is a successor for replacing the column by the foot and the foot, so that the method is good for developing a new column.

Thirdly, the invention is characterized in that: for the retaining wall which is high in the concrete old fort and cannot be removed, or time, labor and materials are wasted due to insanitation; the polder soil below the outer side foot needs to be continuously excavated by the concrete fort with the footing loose soil less firmly, and when the height below the foot of the original retaining wall is increased, the following method is utilized: firstly, the foot protection soil outside the original footing, namely polder soil, is not completely removed, but a groove is dug at intervals of 3-4.5 meters until the position under the old fort, namely 1/3-1/6 soil under the fort is dug into a square pile well foundation pit as shown in the attached figure 1, and how large the pile is dug is, such as: the pile is arranged 1.5 meters square, and then 1.5 meters deep square is dug. The stake is established 1.2 meters square and is just dug 1.2 meters square foundation ditch, it waits that 2/3 wait first, two batches of stake (1/6 is 2 times dig the pile foundation) after casting, dig again after removing the polder and dig out about 30 centimetres thick soil under the former retaining wall foot need water how thick just dig how thick, can not dig more, dig and need fill up with the concrete, tie up the steel reinforcement cage and with the post reserve the concrete retaining wall after the reinforcing bar welding well, analogize with this, confirm the size of design post according to the needs of last old fort bank, all in a word: the whole pile is arranged under the fort foot, the outer side of the pile is aligned or can slightly extend out by about 5 cm, and the size of the pile can bear the weight of the fort. Then, a pile foundation well is dug downwards, the pile foundation can enable the inner side to be vertical, the outer side is expanded outwards again below the ground to be lowered, an expansion slope of 3% -10% of the height of the pile can be formed, the attached figure 2 is the slope of the retaining wall, but the slope restraining of the pile foundation below is slightly larger than the slope of the old fort above, and the pile foundation is enabled to lean against the inner chair; if only about 3-4.5 meters of pile foundation is used, the pile foundation can be expanded by the outer side and the two side surfaces when the hard rock stratum cannot be excavated, namely, both sides can be expanded, one side of the inner surface does not need to be expanded, the foundation is expanded outwards when the hard rock stratum reaches the ground to be excavated, the stress area is increased, the unit area stress is reduced, and the original rock stratum can be excavated without being expanded too much but deeper than the ground; the other side must be enlarged more and the ground surface lowered can be enlarged. After the pile foundation well is dug, a concrete pile is cast, and the size of a steel bar of the concrete pile is not smaller than the size specified conventionally; after the maintenance period is over, if a gap exists between a new pile and the upper retaining wall, stainless metal sheets or other hard wedges are used for wedging, the gap is plugged by concrete slurry, then a second part beside the original non-replaced concrete pile is dug to be replaced by the retaining wall, or the foot can be replaced for three times in total, but only one sixth can be replaced for the first time, one fifth in the middle of five sixth can be replaced for the second time (the pile is still used and is the same as the first time), so the remaining two thirds of every pile support can be replaced for the last time; the method can be only changed into a retaining wall with the thickness of 30 cm, if the retaining wall is not too high, one third of the retaining wall is changed into a pile for the first time, and the concrete retaining wall with the thickness of 30 cm can be completely changed into the concrete retaining wall with the thickness of 30 cm for the second time, and the middle retaining wall is cast when the outer side polder is dug to the required height, and the outer side below the ground of the retaining wall with the thickness of 30 cm is also required to be enlarged to form a footing; however: reserving a part of transverse reinforcing steel bar heads on the first and second columns to be welded with the retaining wall; no gap can be left on the side close to the inner surface of the retaining wall or the column, so that the foundation can not be dug more and can only be filled with concrete when the foundation is dug more, the concrete is preferably used for filling the concrete only on the surface of the template and on the inner surface of the template, and only on the surface of the template and on the inner surface of the template, the concrete is used for filling the concrete when the retaining wall is cast; if the retaining wall above originally is high, the pile can be replaced.

Description of the drawings: FIG. 1 is a schematic front view of a first-time piling foundation pit of the application, 2 is a pile foundation, and 3 is a soil retaining wall; FIG. 2 is a schematic view of a pile face of a pile, wherein FIG. 1 is an original retaining wall; 2 is a pile column, i.e. a pile; 3 is a retaining wall between the piles; 4, enlarging feet under the pile; 5 is the reduced horizon; 6 is a horizon which has not yet decreased; 7 earth retaining space in the earth retaining wall.

Claims

1. A method for replacing a column by stealing feet of a concrete retaining wall is characterized by comprising the following steps: firstly, taking 1/3 or 1/6 place original retaining wall foot to dig a pile column base vertical shaft without removing the polder soil outside the retaining wall, wherein the pile column base is directly inserted below the ground needing to be lowered outside the retaining wall and then outward expands a base foot; the upward slope outside the cast pile is slightly larger than the upward slope of the original retaining wall on the upper side, and the cast pile is leaned against the inner chair and is not expanded outwards; when the pile is cast, only three parts, namely the outer part and two sides, can be used for the template, and the inner part is used for filling concrete; the pile top and the original retaining wall at the upper side are tightly connected without a small gap, and the two sides are required to be reserved with the steel bar heads when the pile is cast and are connected into a whole by welding steel bars when the retaining wall 2/3 between the columns is cast next time.

2. The method for replacing the column by stealing feet of the concrete retaining wall as recited in claim 1: after 1/3 pile casting is completed, the polder to be removed is removed, then the soil with the thickness required by the retaining wall to be cast is dug under the retaining wall, the concrete retaining wall is cast again, the lower side still needs to be under the required terrace and the retaining wall foot is outwards expanded, the inner surface needs to be filled with concrete, the two sides are firmly connected with the steel bar left on the pile, and the top is tightly connected with the retaining wall.

3. The concrete retaining wall of claim 1 or 2, wherein the pile, retaining wall and the joint of the original retaining wall are tightly combined, no gaps exist, especially the pile, and if the gaps exist, the periphery of the pile is sealed by concrete slurry after the pile and retaining wall are wedged by metal sheets which are not easy to generate embroidery.

4. The concrete pile size and the retaining wall thickness of claim 1 are designed as appropriate in consideration of the height of the original retaining wall.

5. The 1/6 of claim 1 being a double foundation and cast pile.