1. A method for rapidly measuring a rammed soil compaction coefficient, which is characterized by comprising the following steps: establishing a relation between a method for detecting the water content of rammed soil in a field and a compaction coefficient, performing accuracy difference adjustment by using a traditional cutting ring method, and establishing a corresponding relation between an electronic numerical value of the water content detection and the compaction coefficient; directly calculating compaction coefficients of other soil layers with the same soil texture by using the water content, and simultaneously recording geographical position information of source soil; and forming a data curve and a database, and directly using the measured water content value to reversely calculate the compaction coefficient when the rammed soil compaction coefficient is detected.

2. The method for rapidly measuring the rammed earth compaction coefficient according to claim 1, wherein the method for rapidly measuring the rammed earth compaction coefficient specifically comprises:

detecting 2/3 positions in a homogeneous collapsible loess layer in a field by using a soil moisture detector, recording and averaging the data acquired by each measuring point, wherein the number of the data is not less than 8;

step two, taking part of the compacted homogeneous soil layer which is subjected to the moisture detection position to carry out measurement by a traditional cutting ring method, recording the soil taking position and measurement data, and calculating a compaction coefficient;

step three, comparing the water content detection and the compacted compaction coefficient, establishing a functional relation, and determining a functional relation formula with the comparison data measured by the cutting ring method;

collecting a large amount of data, carrying out numerical analysis and difference adjustment, and establishing a multi-curve table with different water contents and different soil properties;

and step five, comparing other measured moisture values with a previously established connection curve to estimate the compaction coefficient of the water quality control system, and taking points to verify.

3. The method for rapidly measuring the rammed earth compaction coefficient according to claim 2, wherein in the step one, the number of the measuring points is not less than 8, the more measuring points in the heterogeneous soil layer are, the better the measuring points are, and the serial numbers of the measuring points are arranged according to the corresponding marked positions of a site map.

4. The method for rapidly measuring the rammed earth compaction coefficient according to claim 2, wherein the functional relationship is calculated by the formula:

Ks*W＝K

in the formula: ks-a constant determined by soil characteristics such as water density and water content;

w-water content;

k-rammed soil compaction coefficient.

5. The method for rapidly measuring the compaction factor of rammed earth according to claim 2, wherein in the third step, under the condition of uneven water content, the detection data and the detection position are determined, the soil with different water content and uneven quality is classified, and the soil quality of one type is classified into a curve.

6. The method for rapidly measuring the compaction factor of rammed earth according to claim 2, wherein in step four, when the different soil texture data is sufficient, different curves are established.

Background

For thousands of years, China, as one of four civilized ancient countries, has been urging the past era to change over, and history cultural relics are more than ever. In recent years, along with the flourishing of the country and the inheritance of national characteristic culture, the engineering quality consciousness is stronger and stronger, the safety requirement is stricter and stricter, and along with the continuous deepening of scientific research footsteps, the backfill soil compaction measurement technology has great progress. Most of the Shaanxi regions are collapsible loess, the soil property is high in compressibility, and particularly in an environment with high underground water level, a foundation is prone to sinking, so that the foundation sinks, and finally uneven building settlement is caused. Therefore, it is necessary to use the compaction coefficient as the basic quality index of the engineering. Under the existing building environment, engineering requirements such as construction period compactness, rammed soil area large and the like become a normal state, and the existing methods for measuring the rammed soil compaction coefficient in the market at present are few, for example: the traditional circular knife method, the traditional sand filling method, the non-nuclear density method, the similar penetration method, the hammer falling frequency spectrum type roadbed compaction coefficient rapid measuring instrument and the like can not meet the requirement of rapid detection of the whole area after the backfill soil in the field is tamped.

Through the above analysis, the problems and defects of the prior art are as follows: the existing measuring method for the compaction coefficient of the rammed earth cannot meet the requirement of quickly detecting the whole area of the tamped backfilled earth in a field, so that the compaction coefficient of the rammed earth cannot be detected in a short construction period, and even the detection is abandoned; or after the compaction coefficient is ensured, the construction period node is greatly delayed, the phenomenon of human-machine nest work in engineering construction occurs, and great economic waste is generated.

The difficulty in solving the above problems and defects is:

the sources of the rammed soil are complex, the compacted coefficients after compaction are different, although the direct methods such as the traditional cutting ring method and the like are accurate, the time spent for directly detecting the compacted coefficients is long, the problems need to be solved by summarizing the same soil quality by utilizing one physical property, and meanwhile, the relationship is established by contrasting the compacted coefficients with the soil quality. However, it is difficult to count the electronic moisture data of different soil qualities and accurately conclude the relationship with the compaction coefficient.

The significance of solving the problems and the defects is as follows:

the method greatly saves the time required for detecting the backfill soil in the detection of large-area backfill soil, can also store geographical position information and detection data, and can directly skip a cutting ring sampling link to directly use the electronic moisture data to obtain the corresponding compaction coefficient when meeting the same soil quality in the future.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a method for quickly measuring the compaction coefficient of rammed soil.

The invention is realized in such a way that a method for rapidly measuring the rammed soil compaction coefficient comprises the following steps: establishing a relation between a method for detecting the water content of rammed soil in a field and a compaction coefficient, performing accuracy difference adjustment by using a traditional cutting ring method, and establishing a corresponding relation between an electronic numerical value of the water content detection and the compaction coefficient; directly calculating compaction coefficients of other soil layers with the same soil texture by using the water content, and simultaneously recording geographical position information of source soil; and forming a data curve and a database, and directly using the measured water content value to reversely calculate the compaction coefficient when the rammed soil compaction coefficient is detected.

Further, the method for rapidly measuring the rammed soil compaction coefficient specifically comprises the following steps:

step one, in order to obtain accurate data of soil moisture in rammed soil, 2/3 positions in a homogeneous collapsible loess layer in a field are selected for moisture detection by using a soil moisture detector in consideration of influences of factors such as no evaporation, a probe is ensured to be completely inserted into the soil when being inserted into the detection, a cutting ring sampling space is left for each measuring point, no less than 8 data are collected around the measuring point, a large difference value is removed, and an average value is taken for recording;

and step two, measuring the compacted homogeneous soil layer passing through the moisture detection center position in the step one by using a traditional cutting ring method, calculating a compaction coefficient, and simultaneously recording various information including soil physical parameters, such as a soil sampling geographic position, soil specific conditions, a compaction report and the like of each measuring point so as to prepare for building in the same soil quality or in the same position in the later period. When the soil quality in the rammed soil field is different, a measuring point range is set for each layer of 1000m2 range with different soil quality. The compaction coefficient of the data curve which can call the established relation is directly calculated by using an electronic moisture detection instrument, so that the effect of calibrating the soil property at the geographical position is achieved;

and step three, in order to ensure that the principle of the method is feasible, comparing each group of electronic moisture detection data of the same soil texture with the compaction coefficient obtained by cutting ring sampling, obtaining a mapping function relation, establishing a mathematical formula, and fitting a curve to obtain the correlation coefficient of the mathematical formula. The finally formed single data curve can establish a basic framework for achieving the rapid calculation of the compaction coefficient;

step four, in order to ensure the reliability of the detection data of the method, a large amount of data is collected to carry out formula verification, correlation coefficients are adjusted in difference, different formula curves with different soil qualities and different water contents are perfected, a multi-curve table with different water contents and different soil qualities is established, a calculation formula with different correlation coefficients under different soil qualities is finally formed, and a foundation is established for calculating the rammed soil compaction coefficients;

and step five, besides the measuring points in the step one and the step two, the compaction coefficient of the soil compaction site can be estimated by selecting other established connection curves before the measured moisture values are compared, the measuring points are subjected to compaction coefficient detection by using a cutting ring method and are compared with the estimated compaction coefficient, meanwhile, the data is adjusted to ensure the safety of the estimated compaction coefficient, and the obtained compaction coefficient by using electronic moisture detection and calculation can be used for guiding construction, so that the effect of quickly measuring the soil compaction coefficient is achieved.

Further, in the first step, the number of the measuring points is not less than 8, the more the measuring points on the heterogeneous soil layer are, the better the measuring points are, and the serial numbers are arranged in parallel according to the corresponding marked measuring point positions of the site map.

Further, the calculation formula of the functional relationship is as follows:

Ks*W＝K

in the formula: ks-a constant determined by water density, water and soil properties;

w-water content;

k-rammed soil compaction coefficient.

Further, in the third step, under the condition of uneven water content, determining detection data and detection positions, classifying the soil with different water content and uneven quality into one class, and classifying the soil with one class into one curve.

Further, in the fourth step, when the different soil property data are enough, different multiple curves are established.

By combining all the technical schemes, the invention has the advantages and positive effects that: the invention measures the compaction coefficient of collapsible loess by using a data acquisition and fitting method according to the existing tool, finally calculates to obtain the rammed soil compaction coefficient, realizes the purposes of completely measuring large-area rammed soil, ensuring rapidness and convenience, and little damage to the rammed soil survival surface, and finally summarizes, summarizes and promotes the method into a rapid measurement method.

And storing the local soil property and characteristics aiming at the tested soil property and the detected engineering address, and serving the subsequent engineering foundation construction with similar soil property in the same region.

The method realizes detection data covering soil quality of all regions, and provides efficient, rapid and quality-guaranteed detection service for building foundation construction in the construction process.

Along with the continuous change of natural conditions, the climate is abnormal, regional water level mutation and geological cavities are all potential factors threatening the foundation of the building, and in order to be synchronous with the national rapid construction, the detection system mainly ensures the quality and high efficiency of the detection of the compaction coefficient of the large-area and large-volume backfill soil, and saves time and labor for each large construction.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained from the drawings without creative efforts.

FIG. 1 is a flow chart of a method for rapidly measuring a compaction coefficient of rammed earth provided by an embodiment of the invention.

Fig. 2 is a schematic diagram of a ring cutting method and a moisture detection point arrangement of a field ramming ground provided by an embodiment of the invention.

FIG. 3 is a scatter plot set up by contrast provided by an embodiment of the present invention.

Fig. 4 is a linear graph plotted from a scatter plot according to an embodiment of the present invention.

FIG. 5 is a graph of a reverse calculation of compaction factor using moisture values according to a relationship line as provided by an embodiment of the present invention.

Fig. 6 is a photograph of a collapsible loess experimental field provided in an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Aiming at the problems in the prior art, the invention provides a method for quickly measuring the compaction coefficient of rammed earth, and the invention is described in detail below by combining the attached drawings.

As shown in FIG. 1, the method for rapidly measuring the compaction coefficient of the rammed earth provided by the embodiment of the invention comprises the following steps:

s101, establishing a relation between a method for detecting the moisture content of rammed soil in a field and a compaction coefficient, performing accuracy difference adjustment by using a traditional cutting ring method, and establishing a corresponding relation between an electronic numerical value for detecting the moisture content and the compaction coefficient;

s102, directly calculating compaction coefficients of other soil layers with the same soil texture by using the water content, and simultaneously recording geographical position information of source soil;

and S103, forming a data curve and a database, and directly using the measured water content value to reversely calculate the compaction coefficient when the rammed soil compaction coefficient is detected.

The invention is further described with reference to specific examples.

The soil sample selected in real time according to the ramming soil pressure is preferably homogeneous. The specific operation is as follows:

the features of the present invention will be described in further detail below with reference to the following examples and drawings.

As shown in FIG. 2, all triangle symbol positions (including circle plus triangle symbol) in the field are measured by TDR moisture rapid measuring instrument) Moisture measurements were taken at 2/3 points in the homogenized rammed earth layer prior to the cutting ring sampling while measuring 8 times around the cutting ring.

And vertically smashing the ring cutter at a ramming layer 2/3 with more uniform soil on site for sampling and sealing.

And (3) taking out the sample from the cutting ring coated with vaseline on the inner wall, detecting the compaction coefficient and the water content of the sample, recording the soil taking position and the measured data before compaction, and drawing a scatter diagram as shown in figure 3.

And 4, comparing the data before and after compaction and the compaction coefficient after compaction by referring to fig. 4 to establish a functional relation. The calculation formula is as follows:

Ks*W＝K

in the formula: ks-a constant determined by soil characteristics such as water density and water content;

w-water content;

k-rammed soil compaction coefficient.

For the constant Ks calculated in the formula, Ks of different rammed soils are different, and Ks of the same soil with different water content can also be different. Therefore, the Ks value of each soil is determined by performing soil property tests on the soil.

And collecting a large amount of data, performing numerical analysis and difference adjustment, and establishing a curve table under the water content. And comparing the accuracy, efficiency and the like of the compaction coefficient quick test.

The compaction factor was estimated by comparing other measured moisture values to the previously established relationship curve with reference to FIG. 5 and verified by taking points.

Compared with the traditional method, the method has the advantages that the time consumption is increased by 700 percent, and the capital is saved by 200 percent. The percent of pass reaches one hundred percent, and the target is reached. If sampling points can be increased, the relation curve is more accurate, and the precision is increased accordingly. The instrument is used, except that 8 points of local damage (small holes shown as 2) is caused by starting sampling by using a cutting ring, the tamping field is not damaged by using a pin type moisture detector.

(2) The specific method comprises the following steps:

2/3 positions in homogeneous collapsible loess layers in the field are detected by a soil moisture detector, the data collected by each measuring point is not less than 8, the data are recorded and averaged, and the positions are correspondingly marked according to a field map and the serial numbers are arranged. The number of the measuring points is not less than 5, and the more the measuring points of the heterogeneous soil layer are, the better.

Secondly, measuring a part of the compacted homogeneous soil layer passing through the moisture detection position by using a traditional cutting ring method, recording the soil sampling position and measurement data, and calculating a compaction coefficient.

Thirdly, comparing the water content detection and the compacted coefficient to establish a functional relation. The function accuracy can be ensured by comparing the ring cutting method with the measuring points as many as possible. And simultaneously determining a functional relation by using the comparison data of the two. Meanwhile, under the condition of uneven water content, detection data and detection positions are determined, soil with different water content and uneven quality can be classified into one type, and one type of soil quality can be classified into one type of curve, so that the result is more accurate.

Fourthly, collecting a large amount of data to perform numerical analysis and adjustment, and establishing a multi-curve table with different water contents and different soil qualities.

When the different soil texture data is enough, different multiple curves can be established.

Fifthly, estimating the compaction coefficient of the other measured moisture values according to the established connection curve before comparison, and taking points for verification.

And comparing the accuracy, efficiency and the like of the compaction coefficient quick test. By comparing the error of the compaction coefficient of the scheme and adjusting the difference, the relation function can be more closely attached to the data measured by the traditional cutting ring method. But the security of the detection can be improved by adjusting the coefficients for security reasons.

Aiming at the technical scheme and the operation, the method can be used in engineering examples such as ancient building rammed earth bases (such as Dian clock buildings), airport backfilling, building foundation plain soil backfilling and the like, and a compaction coefficient feedback test is carried out on collapsible loess in northwest regions according to existing theoretical knowledge.

Firstly, setting test fields with different compaction coefficients under the same water content according to the properties of collapsible loess, wherein the test fields are usedAnd (3) blending the moisture of the screened collapsible loess into homogeneous soil with the same moisture content, tamping layer by layer, embedding into an electronic moisture detector, and detecting. Aiming at the test that the same collapsible loess is adopted, the maximum dry density is 1.82g/cm³。

For example, a dry density of 1.4g/cm³In the test field with the water content of 13%, 57 data measuring points are carried out by using an electronic water content detector, and the average value is 17.836. Ks is 0.044 according to the formula.

The dry density was 1.7g/cm³The test field with 13% water content has 49 data points measured by an electronic moisture detector, and the average value is 22.273. Ks is 0.045 obtained according to the formula.

Then the two electronic moisture measurements 15.2 measured at the same location can be used to calculate the compaction coefficients 0.6688 and 0.684 respectively according to the Ks values, with an error of only 0.0152. In practical application, the Ks value can be reduced to be used as a safety redundant value to reach the safety of the compaction coefficient.

In another example, the dry density of the sample is 1.55g/cm³And the homogeneous soil test field with the water content of 8% uses an electronic moisture detector to carry out data measuring points for 39 in total, and the average value is 15.585. Ks was found to be 0.0546 according to the above formula.

Combined with the above dry density of 1.7g/cm³And 1.4g/cm³The average measured data of the electronic moisture meter of the homogeneous soil of (2) was 20.055, and Ks was found to be 0.0425.

According to the test field data with the water content of 13% and 8%, Ks of 0.445 and 0.0546 can be obtained, the larger the water content of the soil body is, the smaller the Ks value is, but the larger the measurement data of the electronic water content detector is.

The functional relation between the water detection value and the compaction coefficient after compaction can be completely deduced according to the compaction coefficient feedback test of the collapsible loess.

According to the test, the method can be directly buried in engineering examples such as ancient building foundations in a layered mode, and whether the holes exist or not can be inferred according to the calculated compaction coefficients. The method can also be used for detecting the compaction coefficient of high-fill airport and building foundation backfill.

The electronic moisture detector can be directly transformed and directly connected with conductors such as reinforcing steel bars, the effect that the conductors such as the reinforcing steel bars can also completely derive moisture data is achieved, and the compaction coefficient is directly inversely calculated through moisture. The method is used for actual test detection, steel bars are buried in each layer of rammed soil, a detection instrument is directly communicated with the steel bars, monitoring can be carried out by using one or more moisture detectors, and the steel bars are pulled out or left in the rammed soil layer after the compaction coefficients are measured and calculated.

The electronic moisture detector used in the present invention may be an electronic device that can measure and display the moisture content of soil, such as a soil moisture detector that displays the moisture content of soil, and may be an electronic device that uses the moisture content of resistivity reaction.

The above description is only for the purpose of illustrating the present invention and the appended claims are not to be construed as limiting the scope of the invention, which is intended to cover all modifications, equivalents and improvements that are within the spirit and scope of the invention as defined by the appended claims.