Seawall mounting project grouting method

Abstract

The invention discloses a seawall diaphragm engineering grouting method, which comprises the following steps of: 1, drilling, 2, slurrying, 3, grouting and 4, sealing holes, in the step 1, drilling by adopting a rotary drilling machine and a diamond or hard alloy drill bit; in the step of pulping in the second step, pulping materials are weighed according to the proportion, and the weighing error should be smaller than 5%; in the third step of grouting, a bottom-to-top segmented grouting method is adopted for grouting, and pure pressure type grouting is adopted for grouting; when consolidation grouting is carried out, the grouting section of the contact part of the concrete and the bedrock is independently grouted and waits to be solidified; the length of the contact section in the rock is not greater than 2m; in the fourth step of hole sealing, after consolidation grouting is finished, a full-hole grouting hole sealing method is adopted for hole sealing; the method has the beneficial effects that the method is practical, the grouting mode is unique and scientific, the grouting efficiency is improved, and the engineering quality is also improved.

Description

Technical Field

[0001] The invention relates to a construction method for a seawall safety project, and in particular to a grouting method for a seawall safety project. Background Art

[0002] The Seawall Safety Project is a comprehensive marine engineering project that aims to protect coastal areas from seawater intrusion, maintain the stability of the coastline, and protect the ecological environment. Seawalls are usually sea retaining walls made of concrete and other materials. They are located at the junction of the coastline and the seawater. Their main function is to prevent the impact of waves and seawater erosion. "Anlan" means a state of stability, calmness, and stability. Therefore, the Seawall Safety Project maintains the stability of the coastline and protects the ecological environment by building seawalls.

[0003] The Seawall Safety Project is a response to the country's need for coastline protection. By building and reinforcing seawalls, it improves flood and tide prevention capabilities and ensures the safety of coastal areas. The project not only focuses on improving flood and tide prevention capabilities, but also pays attention to the protection and restoration of the ecological environment and promotes green development.

[0004] During the construction of seawall safety projects, grouting is particularly important, as it relates to the core quality of the project and the service life of later projects. Therefore, the patent application of this invention is specifically aimed at optimizing and improving the grouting process during the construction of seawall safety projects. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a grouting method for seawall safety engineering in view of the deficiencies in the prior art.

[0006] In order to achieve the above object, the measures taken by the present invention are:

[0007] A grouting method for seawall safety engineering comprises the following steps: first, drilling, second, grouting, third, grouting and fourth, hole sealing.

[0008] The first step of drilling is: drilling with a rotary drill and a diamond or carbide drill bit;

[0009] The second step of pulping is: the pulping materials are weighed according to the proportion, and the weighing error should be less than 5%;

[0010] The third step of grouting is as follows: in the grouting method of the seawall safety project, the grouting adopts the bottom-up segmented grouting method, and the grouting adopts the pure pressure grouting; when the consolidation grouting is performed, the grouting section at the contact part between the concrete and the bedrock is poured separately and waits for solidification; the length of the contact section in the rock is not more than 2 meters, and the length of the following grouting section can be 5 meters to 6 meters, which can be shortened or lengthened, but greater than 10 meters;

[0011] The fourth step of hole sealing is: after the consolidation grouting is completed, the hole is sealed by using the full hole grouting sealing method;

[0012] In the first step of drilling, the borehole should be measured for hole inclination, and the deviation of the bottom of the hole should not be greater than 1.25 meters; after the drilling is completed, the borehole is flushed, and the thickness of the sediment at the bottom of the hole should not exceed 20 centimeters;

[0013] In the third step of grouting, when consolidation grouting is performed, if the length of the rock grouting section in the borehole is not more than 6 meters, grouting can be performed at one time; if it is more than 6 meters, grouting is performed in sections;

[0014] Before the third step of grouting, a water pressure test is performed on the borehole, and after the water pressure test is completed, grouting is performed from bottom to top;

[0015] During the consolidation grouting process of the third step of grouting, when the boreholes are connected to each other, parallel grouting is adopted, but no more than 3 holes are grouted at the same time, and the grouting pressure is controlled to prevent the upper concrete or rock from lifting;

[0016] In the third step of grouting, the grouting pressure is 0.4 MPa, pure pressure grouting is adopted, the pressure gauge is installed on the grouting pipeline of the orifice, the pressure value is read as the median value of the pressure gauge pointer swing, and the pointer swing range is less than 20% of the grouting pressure;

[0017] In the third step of grouting, the grouting slurry should be changed step by step from dilute to concentrated, and the water-cement ratio of the consolidation grouting slurry is 2:1, 1:1, 0.8:1, 0.6:1 or 0.5:1;

[0018] Before the fourth step of sealing, the consolidation grouting termination condition is: under the maximum design pressure of the grouting section, when the injection rate is no more than 0.4L / min and the group hole grouting is no more than 0.8L / min, continue grouting for 30 minutes and end the grouting.

[0019] The invention has the following beneficial effects: it is practical, the grouting method is unique and scientific, the grouting efficiency is improved, and the engineering quality is improved. DETAILED DESCRIPTION

[0020] A grouting method for seawall safety engineering comprises the following steps: first, drilling, second, grouting, third, grouting and fourth, hole sealing.

[0021] The first step of drilling is: drilling with a rotary drill and a diamond or carbide drill bit;

[0022] The second step of slurrying is as follows: the slurrying materials are weighed according to the proportion, and the weighing error should be less than 5%; the slurry must be stirred evenly and the slurry density is measured. The stirring time of pure cement slurry should be no less than 3 minutes when using an ordinary mixer; when using a high-speed mixer, it should be no less than 30 seconds. The slurry should be sieved before use, and the time from preparation to use should be less than 4 hours. The centralized slurrying station should prepare pure cement slurry with a water-cement ratio of 0.5:1. The flow rate of the conveying slurry should be 1.4~2.0m / s. The density of the incoming slurry should be measured at each grouting location and adjusted for use. In cold seasons, the machine room and grouting pipelines should be well protected from cold and heat. In hot seasons, heat and sun protection measures should be taken. The slurry temperature should be kept between 5 and 40°C. If hot water is used for slurrying, the water temperature should not exceed 40°C. The speed and mixing capacity of the mixer should be adapted to the type of slurry being stirred and the displacement of the grouting pump, respectively, and should be able to ensure uniform and continuous mixing of the slurry. The performance of the grouting pump should be adapted to the type and concentration of the slurry. The allowable working pressure should be greater than 1.5 times the maximum grouting pressure, and there should be sufficient grouting volume and stable working performance. A multi-cylinder plunger grouting pump should be used to grout pure cement slurry. The grouting pipeline should ensure smooth flow of slurry and should be able to withstand 1.5 times the maximum grouting pressure. Pressure gauges should be installed at the grouting pump and grouting orifice. The operating pressure should be between 1 / 4 and 3 / 4 of the maximum value of the pressure gauge. The pressure gauge should be calibrated regularly, and unqualified and damaged pressure gauges are strictly prohibited from use. A grouting device should be installed between the pressure gauge and the pipeline. The grouting plug should be adapted to the grouting method, grouting pressure and geological conditions adopted. The rubber plug (ball) should have good expansion and pressure resistance, can reliably seal the grouting hole section under the maximum grouting pressure, and be easy to install and remove. The grouting capacity of the centralized grouting station should meet the grouting needs of all units during the peak grouting period. The pulping station should be equipped with dust removal equipment. When admixtures or additives need to be added to the slurry, corresponding equipment should be added.

[0023] The third step of grouting is: in the grouting method of this seawall safety project, the grouting adopts the bottom-up segmented grouting method, and the grouting adopts pure pressure grouting; when performing consolidation grouting, the grouting section at the contact point between the concrete and the bedrock is grouted separately and waits for solidification; the length of the contact section in the rock is not more than 2 meters, and the length of the following grouting section can be 5 meters to 6 meters, which can be shortened or lengthened, but greater than 10m.

[0024] The fourth step of hole sealing is: after the consolidation grouting is completed, the hole is sealed by the full hole grouting method. The consolidation grouting end condition is: under the maximum design pressure of the grouting section, when the injection rate is not more than 0.4L / min, and the group hole grouting is not more than 0.8L / min, continue grouting for 30 minutes, and the grouting can be ended.

[0025] In the first step of drilling, the borehole should be measured for hole inclination, and the deviation of the bottom of the hole shall not be greater than 1.25 meters; after the drilling is completed, the borehole should be flushed, and the thickness of the sediment at the bottom of the hole shall not exceed 20 centimeters. Among them, the deviation value between the grouting hole position and the designed hole position shall not be greater than 10 centimeters, and the hole depth shall comply with the design requirements. When the drilling encounters caves, collapsed holes or falling blocks that make it difficult to drill, grouting can be carried out first before drilling. If concentrated water leakage or gushing is found, the situation should be investigated, the cause should be analyzed, and drilling should be carried out after treatment. When the drilling operation is temporarily suspended, the hole mouth should be properly protected to prevent sewage from flowing in and foreign objects from falling in.

[0026] In the third step of grouting, when consolidation grouting is performed, if the length of the rock grouting section in the borehole is not more than 6 meters, grouting can be performed at one time; if it is more than 6 meters, grouting is performed in sections. After the grouting of each grouting section is completed, it is generally not necessary to wait for setting, but if there is water gushing before grouting, grouting after grouting, or other complex geological conditions, it is advisable to wait for setting. The waiting time should be determined according to the design requirements and the specific conditions of the project.

[0027] Before the third step of grouting, a water pressure test is performed on the borehole. After the water pressure test is completed, grouting is carried out from bottom to top. Before grouting, each grouting hole is subjected to a fissure flushing with pressurized water until the return water is clean. The flushing pressure can be 80% of the grouting pressure and is not greater than 1MPa. For areas with complex geological conditions such as karst, faults, large fractured zones, weak interlayers, and areas with special design requirements, fissure flushing is carried out according to design requirements. Control the pressure during flushing to prevent the rock formation from lifting and deforming. If any signs of abnormal rock formation are found, immediately stop pressurizing or reducing the pressure. Before grouting, each grouting hole should be subjected to fissure flushing and water pressure test. The purpose of water pressure test is to understand the geological conditions; the distribution of rock layers and the amount of grouting absorbed by the rock layers under the grouting pressure; to check the law that the permeability values ​​of the grouting holes in each order gradually decrease as the grouting order increases; to understand the grouting changes in each section, whether there are any abnormal changes, and to take corresponding measures if there are any abnormalities; different grouting methods and grouting section lengths can also be selected through water pressure test; to understand the permeability of each grouting section before grouting, so as to prepare materials and the initial mix ratio of slurry. The water pressure test is carried out in sections within 24 hours before grouting after crack flushing. The water pressure uses 80% of the grouting pressure. If the water pressure is greater than 1MPa, the test is carried out with 1MPa water pressure. The water pressure test hole can be used in combination with the pilot hole, and 10% of the number of drilled holes is used as the water pressure test hole. Simple water pressure can be combined with crack flushing. The pressure is 80% of the grouting pressure and not greater than 1MPa. The water pressure time is 20min, and the pressure flow rate is measured every 5min. The final flow value is taken as the calculated flow, and the result is expressed as permeability q, with the unit being (Lu).

[0028] During the consolidation grouting process of the third step grouting, when the boreholes are connected to each other, parallel grouting is adopted, but no more than 3 holes are grouted at the same time, and the grouting pressure is controlled to prevent the upper concrete or rock from lifting.

[0029] In the third step of grouting, the grouting pressure is 0.4MPa, and the principle is not to lift the poured concrete block (observation points should be arranged around during grouting). Pure pressure grouting is adopted, and the pressure gauge is installed on the grouting pipeline of the orifice. The pressure value is read as the median value of the pressure gauge pointer swing, and the pointer swing range is less than 20% of the grouting pressure. The grouting should reach the design pressure as soon as possible, but the pressure should be increased in stages for parts with a large injection rate or easy to lift.

[0030] In the third step of grouting, the grouting slurry should be changed step by step from dilute to concentrated, and the water-cement ratio of the consolidation grouting slurry should be 2:1, 1:1, 0.8:1, 0.6:1 or 0.5:1. When grouting stable slurry, mixed slurry and paste slurry, the ratio should be less.

[0031] Before the fourth step of sealing, the consolidation grouting termination condition is: under the maximum design pressure of the grouting section, when the injection rate is no more than 0.4L / min and the group hole grouting is no more than 0.8L / min, continue grouting for 30 minutes and end the grouting.

[0032] The principles of slurry transformation are as follows:

[0033] (1) When the grouting pressure remains unchanged and the injection rate continues to decrease, or when the injection rate remains unchanged and the pressure continues to increase, the water-cement ratio must not be changed.

[0034] (2) When the injection volume of a certain grade of slurry has reached more than 300L, or the grouting time has reached 30 minutes, and the grouting pressure and injection rate have not changed or have not changed significantly, the water-cement ratio of the first grade should be changed.

[0035] (3) When the injection rate is greater than 30L / min, the concentration can be increased according to the specific situation.

[0036] Special situation handling

[0037] (1) When the water permeability or unit mortar injection volume of the final section of the grouting hole is greater than the design specified value, the drilling hole should be further deepened.

[0038] (2) When grouting or leakage is found during the grouting process, it should be handled according to the specific situation by using methods such as caulking, surface sealing, low pressure, thick slurry, flow limiting, quantity limiting, intermittent, and waiting for setting.

[0039] (3) When grouting occurs, if the grouting hole is ready for grouting, grouting should be carried out one pump at a time. Otherwise, the grouting hole should be plugged, and after the grouting of the grouting hole is completed, the grouting hole should be swept and flushed, and then drilling or grouting can continue.

[0040] (4) Grouting must be carried out continuously. If it is interrupted for some reason, it should be handled according to the following principles:

[0041] a. Grouting should be resumed as soon as possible, otherwise the borehole should be flushed immediately and then grouting should be resumed. If flushing is not possible or ineffective, the hole should be swept and then grouting should be resumed;

[0042] b. When resuming grouting, cement slurry with the opening grouting ratio should be used for grouting. If the injection rate is similar to that before the interruption, the cement slurry ratio before the interruption can be used to continue grouting; if the injection rate is much lower than that before the interruption, the slurry should be concentrated step by step and grouting should be continued; if the injection rate is much lower than that before the interruption and the grouting is stopped within a short time, remedial measures should be taken.

[0043] (5) For grouting holes with water gushing out from the hole mouth, the water gushing pressure and water gushing amount should be measured and recorded before grouting. According to the water gushing situation, the following comprehensive treatment measures can be selected:

[0044] a. Grouting in sections from top to bottom; b. Shorten the section length; c. Increase the grouting pressure; d. Carry out pure pressure grouting; e. Pour concentrated slurry; f. Pour quick-setting slurry; g. Screen slurry; h. Close the slurry; i. Wait for setting; j. Seal the hole by section grouting or full-hole grouting.

[0045] (6) When the injection volume of the grouting section is large and difficult to complete, the following measures can be used:

[0046] a. Low pressure, thick slurry, limited flow, limited quantity, intermittent grouting;

[0047] b. Infuse quick-setting slurry;

[0048] c. Pour mixed slurry or paste slurry.

[0049] (7) If the grout becomes thicker during the grouting process, you can use new grout with the same water-cement ratio. If the effect is not obvious, continue grouting for 30 minutes and then end the grouting without re-grouting.

[0050] (8) When a grouting hole section encounters special circumstances, no matter what measures are adopted, the hole should be cleaned before re-grouting, and the specified termination conditions should be met after re-grouting.

Claims

1. A grouting method for seawall safety engineering, comprising a first step of drilling, a second step of slurry preparation, a third step of grouting and a fourth step of sealing the hole, characterized in that: The first step of drilling is: drilling with a rotary drill and a diamond or carbide drill bit; The second step of pulping is: the pulping materials are weighed according to the proportion, and the weighing error should be less than 5%; The third step of grouting is as follows: in the grouting method of the seawall safety project, the grouting adopts the bottom-up segmented grouting method, and the grouting adopts the pure pressure grouting; when the consolidation grouting is performed, the grouting section at the contact part between the concrete and the bedrock is poured separately and waits for solidification; the length of the contact section in the rock is not more than 2 meters, and the length of the following grouting section can be 5 meters to 6 meters, which can be shortened or lengthened, but greater than 10 meters; The fourth step of hole sealing is: after the consolidation grouting is completed, the hole is sealed by a full hole grouting sealing method.

2. A grouting method for seawall safety engineering according to claim 1, characterized in that: In the first step of drilling, the borehole should be measured for hole inclination, and the deviation of the bottom of the hole should not be greater than 1.25 meters; after the drilling is completed, the borehole is flushed, and the thickness of the sediment at the bottom of the hole should not exceed 20 centimeters.

3. A grouting method for seawall safety engineering according to claim 1 or 2, characterized in that: In the grouting of the third step, when consolidation grouting is performed, if the length of the rock grouting section in the borehole is not more than 6 meters, grouting can be performed at one time; if it is more than 6 meters, grouting is performed in sections.

4. A grouting method for seawall safety engineering according to claim 3, characterized in that: Before the third step of grouting, a water pressure test is performed on the borehole. After the water pressure test is completed, grouting is performed from bottom to top.

5. A grouting method for seawall safety engineering according to claim 4, characterized in that: During the consolidation grouting process of the third step grouting, when the boreholes are connected to each other, parallel grouting is adopted, but no more than 3 holes are grouted at the same time, and the grouting pressure is controlled to prevent the upper concrete or rock from lifting.

6. A grouting method for seawall safety engineering according to claim 5, characterized in that: In the third step of grouting, the grouting pressure is 0.4MPa, pure pressure grouting is adopted, the pressure gauge is installed on the orifice grouting pipeline, the pressure value is read as the median value of the pressure gauge pointer swing, and the pointer swing range is less than 20% of the grouting pressure.

7. A grouting method for seawall safety engineering according to claim 6, characterized in that: In the third step of grouting, the grouting slurry should be changed step by step from dilute to concentrated, and the water-cement ratio of the consolidation grouting slurry adopts five ratios of 2:1, 1:1, 0.8:1, 0.6:1 or 0.5:

1.

8. A grouting method for seawall safety engineering according to claim 7, characterized in that: Before the fourth step of sealing, the consolidation grouting termination condition is: under the maximum design pressure of the grouting section, when the injection rate is no more than 0.4L / min and the group hole grouting is no more than 0.8L / min, continue grouting for 30 minutes and end the grouting.