CN113668504B

CN113668504B - Grooving emergency reinforcing construction method for diaphragm underground diaphragm wall

Info

Publication number: CN113668504B
Application number: CN202110960919.5A
Authority: CN
Inventors: 林海; 钱福健; 钮峰; 刘亚松; 全有维
Original assignee: Third Construction Co Ltd of China Construction Eighth Engineering Divison Co Ltd
Current assignee: Third Construction Co Ltd of China Construction Eighth Engineering Divison Co Ltd
Priority date: 2021-08-20
Filing date: 2021-08-20
Publication date: 2022-07-22
Anticipated expiration: 2041-08-20
Also published as: CN113668504A

Abstract

The invention provides a grooving emergency reinforcing construction method for an intermediate diaphragm underground diaphragm wall, which comprises the following steps: s1, protecting a collapse section guide wall and a groove section; s2, ultrasonic groove section detection; s3, forming holes at two sides of the groove section, and arranging partition steel bars; s4, filling collapse sections; and S5, performing double-liquid reinforcement treatment. The method is quick and efficient in treating the surface layer collapse of the groove wall of the middle partition underground continuous wall, and improves the construction quality of the middle partition underground continuous wall on the basis of guaranteeing the life safety of construction personnel.

Description

Grooving emergency reinforcing construction method for diaphragm underground diaphragm wall

Technical Field

The invention relates to the technical field of underground continuous walls, in particular to a grooving emergency reinforcing construction method for an intermediate underground continuous wall.

Background

The underground continuous wall is a foundation engineering, and adopts a trenching machine on the ground, a long and narrow deep groove is excavated under the condition of slurry wall protection along the peripheral axis of the deep excavation engineering, after the groove is cleaned, a steel reinforcement cage is hung in the groove, then underwater concrete is poured by a conduit method to form a unit groove section, and the steps are carried out section by section, so that a continuous reinforced concrete wall is built underground to be used as a structure for intercepting water, preventing seepage, bearing and retaining water. The method has the characteristics of small construction vibration, high wall rigidity, good integrity, high construction speed, capability of saving earth and stone, capability of constructing deep foundation pit support in dense building groups and performing reverse construction, capability of being used for construction in various geological conditions including sandy soil layers and gravel layers with the particle size of less than 50mm, and the like. The method is suitable for building basements, underground markets, parking lots, underground oil depots, retaining walls, deep foundations of high-rise buildings, reverse construction building envelopes, deep pools and pits of industrial buildings, vertical shafts and the like of buildings.

At present, in the construction process of the middle-partition underground continuous wall, the groove wall of the middle-partition underground continuous wall is not designed for reinforcement, and thick filling soil exists on the surface layer in a construction site, so that the surface layer of the groove wall of the middle-partition underground continuous wall is easy to collapse.

Disclosure of Invention

Aiming at the prior art, the invention provides a grooving emergency reinforcing construction method for an intermediate diaphragm underground continuous wall, so as to improve the construction quality of the intermediate diaphragm underground continuous wall.

The invention provides a grooving emergency reinforcing construction method for an intermediate diaphragm underground diaphragm wall, which comprises the following steps of:

s1, protecting the guide wall and the groove section of the collapse section;

s2, detecting the ultrasonic groove section; the method comprises the following specific steps: carrying out fine measurement on the collapse condition of the groove section by utilizing ultrasonic waves, and forming a plane position diagram and a depth shape diagram of the collapse hole condition;

s3, forming holes at two sides of the groove section, and arranging partition steel bars; the method comprises the following specific steps: a plurality of drill holes are formed in the landslide section guide wall along the length direction, phi 12 or phi 14 partition steel bars are vertically inserted into the drill holes, and the partition steel bars vertically penetrate through the lower layer of the landslide soil body and are fixed;

s4, filling collapse sections; the method specifically comprises the following steps: according to the hole collapse situation plane position graph and the depth shape graph, a plurality of backfill holes are formed in the collapsed section guide wall or the temporary sidewalk along the length direction, and backfill soil is filled in the backfill holes; in filling, stirring the backfill soil in the backfill holes by using low pressure by using high-pressure rotary spraying equipment until the backfill soil is backfilled to the lower opening of a concrete surface layer to form a backfill soil body;

s5, performing double-liquid reinforcement treatment; the method specifically comprises the following steps: and (4) pouring mixed slurry in the gaps on the backfilled soil body.

Preferably, in S1, specifically: and (3) preliminarily determining the collapse range by utilizing ultrasonic wave, then closing the site, and forbidding various heavy-duty vehicles to pass in the collapse range influence area and the peripheral 5m range.

Preferably, in S2, the precise measurement includes: the length of each underground continuous wall is 6m, the detection is carried out every 1m along the length direction, and a plane position diagram and a depth shape diagram of the hole collapse condition are formed by utilizing 5 groups of ultrasonic grooving result diagrams.

Preferably, in S3, the distance between the drill holes is 200-250mm, and the hole diameter of the drill holes is 15-20 mm.

Preferably, in S4, the pore diameter of the backfill hole is 400-500 mm; the backfill soil is composed of adjusting slurry and broken stones with the particle size of less than or equal to 20mm, and the parameters of the adjusting slurry are as follows: the mud specific gravity is not less than 1.15, and the consistency is not less than 28 seconds.

Preferably, in S5, the diffusion radius of the mixed slurry is controlled to be 2m, and the initial setting time of the mixed slurry is controlled to be within 2 min.

Preferably, in S5, the depth of the perfusion is controlled to be 1-10m below a natural floor, the pressure of the perfusion is controlled to be 0.7-3.5MPa, and the perfusion concentration of the mixed slurry is gradually changed from thin to thick.

Preferably, in S5, the mixed slurry is a cement slurry-water glass double liquid.

Preferably, the cement slurry is a silicate cement slurry; the water glass is a water glass stock solution with the concentration of Be =30-40 and the modulus M = 2.8-3.1.

Preferably, the volume ratio of the cement paste to the water glass is 1: 1.

Compared with the prior art, the invention has the beneficial effects that

1. The invention adopts measures of adjusting slurry, cutting off reinforcing steel bars and the like, can effectively prevent the continuous collapse of the soil body of the groove section, and provides favorable conditions for the filling and the double-liquid reinforcement treatment of the subsequent collapse section. The partition reinforcing steel bars can also prevent backfill or common soil from entering the groove section in a large quantity, and waste is avoided. And the gap is filled by adopting double-liquid grouting, and loose low-pressure rotary-jetting backfill glue is integrated, so that the stability of the groove wall is improved.

2. The method has the advantages that the surface layer collapse treatment of the groove wall of the intermediate underground diaphragm wall is rapid and efficient, and the construction quality of the intermediate underground diaphragm wall is improved on the basis of guaranteeing the life safety of construction personnel.

3. The invention has the advantages of common machinery, simple process and method, quick disposal, meeting the requirement of emergency disposal, ensuring the construction safety and simultaneously ensuring the construction progress.

Drawings

Fig. 1 is a schematic flow chart of an emergency reinforcement construction method for grooving of a diaphragm underground diaphragm wall according to an embodiment of the invention.

Fig. 2-4 are schematic construction structures of the embodiment of the invention.

In the figure, 1, a groove section; 2. an underground diaphragm wall; 3. a landslide section guide wall; 4. drilling; 5. separating the reinforcing steel bars; 6. backfilling the hole; 7. original reinforcing steel bars.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below by combining the specific drawings.

Examples

As shown in fig. 1-4, a construction method for grooving and emergency reinforcing of an intermediate underground diaphragm wall comprises the following steps:

s1, protecting the guide wall and the groove section of the collapse section: preliminarily measuring by using an ultrasonic detector, preliminarily determining a collapse range, and then closing the site, wherein various heavy-duty vehicles are forbidden to pass through in an affected area of the collapse range and a peripheral 5m range;

s2, ultrasonic wave groove section detection: in order to determine the position and the quantity of subsequent drilling holes, an ultrasonic detector is utilized to carry out fine measurement on the collapse condition of the groove section 1, each length of the underground continuous wall 2 is 6m, the detection is carried out once every 1m along the length direction, and 5 groups of ultrasonic grooving result graphs are utilized to form a hole collapse condition plane position graph and a depth shape graph;

s3, holes are formed in two sides of the groove section, and partition steel bars are arranged: referring to FIGS. 2-4, a plurality of drill holes 4 are formed in the position, 300mm away from the inner side edge of the guide wall 3 of the collapse section along the length direction by adopting an electric hammer, phi 12 partition steel bars 5 are vertically inserted into the drill holes 4 according to the staggered arrangement of the original steel bars 7 in the guide wall 3 of the collapse section, and the partition steel bars 5 vertically penetrate into the lower layer of the collapse soil body and are fixed by matching with manual work of a digging machine; wherein the distance between adjacent drill holes 4 is 230mm, and the aperture of each drill hole 4 is 18 mm;

s4, filling collapse section: referring to fig. 4, according to the plan position diagram and the depth shape diagram of the hole collapse situation, a backfill hole 6 is arranged on the collapse section guide wall 3 along the length direction by adopting a water drilling machine and a pickaxe at each 1.5m, the backfill hole 6 is formed from the outer side edge of the collapse section guide wall 3 to 1/3 of the groove section 1, and backfill soil is filled in the backfill hole 6 by adopting a PC60 excavator;

in filling, the filling speed is controlled, the deformation condition of the partition steel bars 5 is observed, whether the partition steel bars 5 are completely deformed or dislocated is judged, and if the dislocated partition steel bars are completely deformed or dislocated, the partition steel bars are immediately supplemented;

during filling, the backfill cannot be tamped tightly, gaps are still quite dispersed, the backfill in the backfill holes 6 is stirred by a high-pressure rotary spraying machine through low pressure for continuous construction for 15min, equipment is removed after rotary spraying and uniform stirring, whether the soil body is settled or not is observed, and if the settlement is obvious, the backfill is manually filled again to the lower opening of the concrete surface layer to form the backfill soil body; wherein, the high-pressure jet grouting machine is adopted to reduce the cement slurry pressure of the jet grouting pile, the pressure is controlled to be about 1MP a, and the cement slurry and the backfill soil are uniformly mixed and solidified into a solidified body so as to achieve the effect of stabilizing the wall of the tank;

in the process, an ultrasonic detector is adopted for continuous ultrasonic detection;

wherein the aperture of the backfilling hole 6 is 450 mm; the backfill consists of adjusting slurry and crushed stones with the particle size less than or equal to 20mm, and the parameters of the adjusting slurry are as follows: the mud has the specific gravity of 1.15 and the consistency of 28 seconds, so as to prevent the soil body of the groove section 1 from continuously collapsing;

s5, double-liquid reinforcement treatment: filling mixed slurry in gaps existing in the backfilled soil body by adopting a double-liquid grouting machine; aiming at the analysis that the backfill soil body influences the stability of the wall of the underground continuous wall, and combining the construction condition of the prior low-pressure jet grouting pile reinforcement, the slurry proportion is reasonably selected to ensure the effective diffusion radius of the mixed slurry;

the diffusion radius of the mixed slurry is controlled to be 2m, the initial setting time of the mixed slurry is controlled to be 2min, the filling depth is controlled to be 5m below a natural terrace, the filling pressure is controlled to be 2.5MPa, and the filling concentration of the mixed slurry is gradually changed from dilute to concentrated.

The mixed slurry is a cement slurry-water glass double liquid, and the cement slurry is silicate cement slurry; the water glass is selected from water glass stock solution with the concentration Be =35 and the modulus M =3.0, the volume ratio of the cement paste to the water glass is 1:1, and the cement mixing amount in the cement paste is not too large in consideration of excavation difficulty in the future and is controlled to be 10%.

Along with the requirement of the country and the industry on green environmental protection is higher and higher, this embodiment has promoted mesophragma underground continuous wall construction quality through ways such as adjustment dado parameter, add the wall reinforcing bar, low pressure jet grouting and biliquid slip casting of mud, has avoided the condition that midboard "belly" and later stage excavation were abolished, has practiced thrift concrete and material, and economic benefits and environmental benefit are showing, and to similar engineering, this embodiment has fabulous popularization and application and worth.

In the implementation process of the embodiment, the use of concrete and materials is reduced, the construction period is shortened, the emission of construction waste is reduced, the environment is protected, the method is economical and applicable, and the national environment-friendly policy for improving the resource utilization rate is met.

The above description is only an embodiment of the present invention, and is not intended to limit the scope of the present invention, and all equivalent structures made by using the contents of the present specification and the drawings can be directly or indirectly applied to other related technical fields, and are also within the scope of the present invention.

Claims

1. The emergency reinforcing construction method for the groove forming of the diaphragm underground diaphragm wall is characterized by comprising the following steps of:

s1, protecting a collapse section guide wall and a groove section;

s2, ultrasonic groove section detection; the method specifically comprises the following steps: carrying out fine measurement on the collapse condition of the groove section by utilizing ultrasonic waves, and forming a plane position diagram and a depth shape diagram of the collapse hole condition;

s3, forming holes at two sides of the groove section, and arranging partition steel bars; the method comprises the following specific steps: a plurality of drill holes are formed in the landslide section guide wall along the length direction, partition reinforcing steel bars are vertically inserted into the drill holes, and the partition reinforcing steel bars vertically penetrate through the lower layer of the landslide soil body and are fixed;

s4, filling collapse sections; the method comprises the following specific steps: according to the hole collapse situation plane position graph and the depth shape graph, a plurality of backfill holes are formed in the collapsed section guide wall or the temporary sidewalk along the length direction, and backfill soil is filled in the backfill holes; in filling, stirring the backfill soil in the backfill hole by using low pressure by adopting high-pressure rotary spraying equipment until the backfill soil is backfilled to the lower opening of the concrete surface layer to form a backfill soil body;

2. The grooving emergency reinforcing construction method for the diaphragm underground diaphragm wall according to claim 1, wherein in the step S1, the concrete steps are as follows: and (3) preliminarily determining the collapse range by utilizing ultrasonic wave, then closing the site, and forbidding various heavy-duty vehicles to pass in the collapse range influence area and the peripheral 5m range.

3. The grooving emergency reinforcing construction method for the diaphragm underground diaphragm wall according to claim 1, wherein in S2, the precise measurement specifically comprises: the length of each underground continuous wall is 6m, detection is carried out every 1m along the length direction, and a plane position diagram and a depth shape diagram of hole collapse conditions are formed by utilizing 5 groups of ultrasonic grooving result diagrams.

4. The emergency reinforcement construction method for the partitioning underground continuous wall as claimed in claim 1, wherein in S3, the distance between the drill holes is 200-250mm, and the aperture of the drill holes is 15-20 mm.

5. The emergency reinforcement construction method for the middle and underground diaphragm wall as claimed in claim 1, wherein in S4, the diameter of the backfill hole is 400-500 mm; the backfill consists of adjusting slurry and crushed stones with the particle size less than or equal to 20mm, and the parameters of the adjusting slurry are as follows: the mud weight is not less than 1.15, and the consistency is not less than 28 seconds.

6. The trenching emergency reinforcement construction method for the diaphragm underground continuous wall as claimed in claim 1, wherein in S5, the spreading radius of the mixed slurry is controlled to be 2m, and the initial setting time of the mixed slurry is controlled to be within 2 min.

7. The trenching emergency reinforcement construction method for the diaphragm underground diaphragm wall as claimed in claim 1, wherein in S5, the depth of the pouring is controlled to be 1-10m below the natural terrace, the pressure of the pouring is controlled to be 0.7-3.5MPa, and the pouring concentration of the mixed slurry is gradually changed from thin to thick.

8. The grooving emergency reinforcing construction method for the diaphragm underground diaphragm wall according to claim 1, wherein in the step S5, the mixed slurry is a cement slurry-water glass double liquid.

9. The grooving emergency reinforcing construction method for the diaphragm underground continuous wall according to claim 8, wherein the cement paste is silicate cement paste; the water glass is a water glass stock solution with the concentration of Be =30-40 and the modulus M = 2.8-3.1.

10. The grooving emergency reinforcing construction method for the diaphragm underground continuous wall according to claim 8 or 9, wherein a volume ratio of the cement paste to the water glass is 1: 1.