CN110130301B - Method for determining bearing capacity characteristic value of rammed/compacted fill layer - Google Patents
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- 238000000034 method Methods 0.000 title claims abstract description 23
- 239000002689 soil Substances 0.000 claims abstract description 92
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- 238000012360 testing method Methods 0.000 claims abstract description 44
- 239000002245 particle Substances 0.000 claims abstract description 22
- 238000011835 investigation Methods 0.000 claims abstract description 6
- 238000005070 sampling Methods 0.000 claims abstract description 6
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- 239000011435 rock Substances 0.000 claims description 13
- 230000005484 gravity Effects 0.000 claims description 12
- 238000012417 linear regression Methods 0.000 claims description 12
- 238000010008 shearing Methods 0.000 claims description 11
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- 238000011065 in-situ storage Methods 0.000 claims description 7
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- 238000004364 calculation method Methods 0.000 claims description 4
- 238000010276 construction Methods 0.000 claims description 4
- 239000011362 coarse particle Substances 0.000 claims description 3
- 239000000758 substrate Substances 0.000 claims description 3
- 230000005483 Hooke's law Effects 0.000 claims description 2
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- 229910000831 Steel Inorganic materials 0.000 description 3
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D1/00—Investigation of foundation soil in situ
- E02D1/02—Investigation of foundation soil in situ before construction work
- E02D1/022—Investigation of foundation soil in situ before construction work by investigating mechanical properties of the soil
Abstract
The invention provides a method for determining a characteristic value of the bearing capacity of a rammed/compacted fill layer. The method for determining the characteristic value of the bearing capacity of the rammed/compacted fill layer is based on the foundation treated by using the Keanshi stone backfill with different grain diameters and performing dynamic ramming (compaction) on the foundationDetermining characteristic value of bearing capacity, specifically applying the characteristic value of bearing capacity estimated by shear strength indexes (c, phi) of field direct shear test, analyzing sampling particles of drill hole and carrying out extra-heavy dynamic sounding (N) in drill hole120) The hammering numbers are corresponded, the corresponding relation between the bearing capacity characteristic value and the overweight dynamic exploration value is established, the bearing capacity characteristic value of the rammed/compacted foundation soil layer can be accurately and quickly determined through the established corresponding relation, and a relatively accurate bearing capacity characteristic value evaluation basis is provided for dereferencing and evaluating the rammed foundation and the compacted foundation in geotechnical engineering investigation work.
Description
Technical Field
The invention relates to the technical field of geotechnical engineering investigation, in particular to a method for determining the bearing capacity characteristic of a tamped fill layer by adopting an in-situ test method.
Technical Field
The domestic metallurgical steel plant material yard is mostly positioned at the river side or the sea side, the project construction material pile foundation is mostly subjected to dynamic compaction foundation treatment, and the grading pile loading compaction is carried out in the using process. Under the requirements of environmental protection upgrading and intelligent modification, some original A-type material strips need to be modified into closed C-type material strips, physical and physical indexes, particularly shear strength indexes, of a foundation dynamic compaction filling layer need to be accurately measured, according to the current geotechnical engineering survey specification (GB50021-2001), the survey of the filling layer mainly comprises in-situ tests including field load tests, field direct shear tests and dynamic sounding tests, however, the dynamic compaction filling materials of the dynamic compaction foundation are mostly mountain cutting rock residues, incoming materials cannot be sorted in the tamping construction process, some ramming materials are boulders, some ramming materials are cohesive soil, the difference of the ramming materials is large, in addition, because the ramming filling soil is compacted by the open-air graded loading and compaction of mineral materials, the specific value of the bearing capacity is relatively high, the surface layer of the ramming layer is hardened, when a large-area load test is adopted, because the loading load is limited, the influence depth is difficult to reach the bottom of the ramming layer and below the bottom of the ramming layer, and technical innovation is needed for accurately determining the bearing capacity characteristic value, the deformation modulus and the shear strength index of the ramming/compacting filling by adopting scientific means.
The ramming/compacting backfill material is a special rock-soil, has the characteristics of artificial filling and natural soil, is an artificial foundation, has a certain thickness, is not sorted, and has close relation between the bearing capacity characteristic value and the particle size, content, water content and the like, a load test is limited by loading and influenced depth and cannot accurately reflect the deformation modulus index of the bearing capacity characteristic value of each filling layer, and how to utilize the field shearing test result to establish the corresponding relation between the ramming/compacting filling superheavy type dynamic sounding with different particle sizes and the bearing capacity characteristic value and the deformation modulus is very important for geotechnical engineering investigation and foundation detection.
Disclosure of Invention
The invention aims to overcome the defects of the technical background and provides a method for measuring the bearing capacity characteristic of rammed/compacted filling, which applies the bearing capacity characteristic value of the rammed filling determined by the field shear test result to establish a relation table of the bearing capacity characteristic value and the extra-heavy dynamic sounding and also establishes an empirical formula for determining the bearing capacity characteristic value and the deformation modulus by using the extra-heavy dynamic sounding, thereby solving the problem of limited influence depth of a large-area load test and having strong engineering practicability.
In order to solve the problems, the invention provides a method for determining a characteristic value of bearing capacity of a rammed/compacted fill, which is characterized by comprising the following specific steps of:
(1) drilling and sampling the filling soil of the rammed/compacted layer on a construction site, classifying filling soil layers of the rammed/compacted layer according to different contents of filling particle sizes by combining the source characteristics of the rock-breaking material obtained by ramming/compacting and a foundation treatment process, and layering drill holes according to thickness;
(2) to stepRespectively carrying out on-site direct shear tests on different ramming/compacting filling layers in the step (1), obtaining the cohesive force c and the internal friction angle phi of the shear strength index soil of various filling layers by using measured values, and calculating the bearing capacity characteristic value f of various filling layers by using the shear strength indexak(kPa), the calculation formula is as follows:
fak＝Mbγb+Mdγmd+McC
in the formula: f. ofak-characteristic value of foundation bearing capacity (kpa) determined by shear strength index of the soil;
Mb、Md、Mc-a load factor;
gamma-the gravity of the soil below the basal floor (kN/m)3) Taking the floating gravity below the underground water level;
γmweighted average gravity (kN/m) of the soil above the base3) Taking the effective gravity of a soil layer below the underground water level;
d-base embedment depth (m);
b, the width (m) of the bottom surface of the foundation is taken as 6m when the width is larger than 6m, and is taken as 3m when the width is smaller than 3 m;
c-standard value of cohesive force (kpa) of soil in the depth range of one time of the width of the short side under the substrate.
The width b of the bottom surface of the foundation takes a value of 6, when the bearing capacity of the foundation of the ramming/compacting filling layer is calculated, the embedding depth of the foundation is considered according to 0, namely d takes a value of 0;
(3) in the step (2), within the range of the direct shearing test point distance of 1.0m, adopting extra-heavy cone dynamic sounding (N)120) Performing in-situ test with continuous test depth, penetrating the rammed/compacted filling layer, recording the hammering number of each filling layer, and performing ultra-heavy dynamic sounding (N) in each drill hole120) The measured hammering number corresponds to the rammed/compacted filling layers with different classified particle sizes, and a corresponding relation table of the bearing capacity characteristic values of different types of filling layers and the extra-heavy dynamic sounding hammering number is established;
(4) analyzing by a scatter diagram, and then obtaining bearing characteristic values (f) of different types of fill layers by linear regressionak) Andultra-heavy dynamic sounding hammering number N120(hit) relation equation:
fak＝a+bN120
wherein a and b are constants which can be directly obtained by linear regression according to the relation table established in the step (3); when geotechnical engineering investigation work is carried out in the later stage, the bearing capacity characteristic value of the similar filling layer is directly calculated according to the equation according to the actually measured ultra-heavy dynamic sounding hammering number.
The further technical scheme of the invention is as follows: the classification of the ramming/compacting layer filling in the step (1) is as follows:
a. filling a soil layer with rock blocks: wherein the total content of the lump stones with d being not less than 200mm and the crushed stones with d being less than 60mm and less than 200mm is 15-50%, the content of the lump stones is greater than the content of the crushed stones, and coarse grained soil, fine grained soil and cohesive soil are mixed;
b. and (3) gravel filling layer: wherein d is not less than 200mm lump stones and 60mm is not less than 60mm and less than 200mm broken stones, the total content of the broken stones is 15% -50%, the content of the broken stones is greater than the content of the lump stones, and coarse grained soil, fine grained soil, silt and clay are mixed;
c. gravel filling layer: wherein the content of gravel with the size of 2mm < d < 60mm is 15% -50%, and is mixed with lump stone, sand soil and clay soil;
d. clay-particle soil mixed gravel filling layer: wherein the content of sticky particles in the soil with the size of 0.005mm < d < 0.0075mm is more than 50%, and the content of coarse particles with the size of d > 2mm is 25% -50%.
The invention has the following excellent technical scheme: the direct shearing test in the step (2) adopts a flat pushing method, the shearing load is parallel to the shearing surface, and the shearing area is 1.0m2And the height is 0.5m, 3 groups of tests are carried out on each type of the shown rock block filling, the broken stone filling, the gravel filling and the clay-soil mixed gravel filling, and the normal stresses of the rock block filling, the broken stone filling, the gravel filling and the clay-soil mixed gravel filling are respectively 150T, 300T, 450T and 600T.
The further technical scheme of the invention is as follows: bearing characteristic values (f) of four different fill layers in the step (4)ak) Number of hammering of super-heavy dynamic sounding120The equation of the relationship is as follows:
filling a soil layer with rock blocks: f. ofak＝20+31N120
And (3) gravel filling layer: f. ofak＝25+25N120
Gravel filling layer: f. ofak＝30+23N120
Filling the cohesive soil mixed with gravel: f. ofak＝35+19N120。
The further technical scheme of the invention is as follows: calculating the bearing capacity characteristic value f of various fill layers in the step (2)akThen, the deformation modulus E of the block stone filling, the broken stone filling, the gravel filling and the clay-soil mixed gravel filling is respectively calculated0Modulus of deformation E0Establishing extra-heavy dynamic sounding N according to Hooke's law experience of solid materials and corresponding acquisition of the same type of materials according to known bearing capacity characteristic values and comparison with standard parameter tables such as engineering geological handbook (fifth edition)120And modulus of deformation E0Analyzing the data in the corresponding relation table through a scatter diagram, and obtaining the deformation modulus E of different types of filling soil through linear regression0Number of hammering of super-heavy dynamic sounding120The relation equation is as follows:
filling a soil layer with rock blocks: e0＝3.5+1.9N120
And (3) gravel filling layer: e0＝4.0+1.5N120
Gravel filling layer: e0＝4.5+1.3N120
Filling the cohesive soil mixed with gravel: e0＝5.0+1.0N120。
The invention has the beneficial effects that:
1. the invention classifies the filling layers according to the content of different filling particles, obtains the cohesive force c and the internal friction angle phi of the shear strength index soil of different filling layers through a shear test, then calculates the bearing capacity characteristic value of different filling layers, and drills holes around the shear test point to carry out the penetration test by adopting the extra-heavy cone power (N)120) Carrying out in-situ test, classifying the tested hammering number and the category of the filling layer to establish a corresponding relational table of the ultra-heavy dynamic sounding hammering number and the bearing capacity characteristic value of different types of rammed/compacted filling, and carrying out in-situ test on the ultra-heavy dynamic sounding hammering number and the bearing capacity characteristic value of the filling layerThe numerical value adopts a linear regression mode to obtain an empirical equation of the ultra-heavy dynamic sounding and the bearing capacity characteristic value of different types of rammed (pressed) filling, fills the blank that the ultra-heavy dynamic sounding is adopted to determine the bearing capacity characteristic value of the rammed (pressed) filling in the engineering geological handbook and relevant specifications, can directly calculate the bearing capacity characteristic value of different filling layers through the empirical equation in the later period of real time, and has simple and convenient calculation mode;
2. according to the method, the deformation modulus of different filling layers can be calculated while the corresponding table of the bearing capacity characteristic value and the overweight dynamic sounding hammering number is obtained, the corresponding table between the overweight dynamic sounding hammering number and the deformation modulus of different filling layers is established, the empirical equation of the overweight dynamic sounding hammering number and the deformation modulus is obtained, and the deformation modulus values of different filling layers can be obtained while the bearing capacity characteristic value is determined;
the invention provides a method for determining the characteristic value of the bearing capacity of rammed (compacted) filling soil, which is more convenient and economic besides a load test method, and simultaneously overcomes the problem of limited influence depth of a large-area load test, and has strong engineering practicability.
Drawings
FIG. 1 shows the force-bearing characteristic values (f) of four types of fill in the examplesak) Number of hammering of super-heavy dynamic sounding120Linear regression plots of (hits);
FIG. 2 shows the deformation modulus (E0) and the number N of ultra-heavy dynamic penetration hammers of the four types of soil in the example120Linear regression plot of (hits).
Detailed description of the invention
The invention is further illustrated with reference to the following figures and examples.
The method for determining the bearing capacity characteristic value of the rammed (compacted) filling soil layer provided by the embodiment specifically comprises the following steps:
(1) the drilling sample classifies the fill by particle size (d) content. Drilling and sampling the filled soil of the rammed (compacted) layer, sending the soil to a laboratory for particle size analysis, and measuring the mass content percentages of the rock blocks, the broken stones, the pebbles, the stone chips, the cobbles, the round cobbles, the gravel sand, the coarse gravel, the medium sand and the cohesive soil. Combining with ramming (compacting) to obtain the source characteristics of the rock-breaking material and foundation treatment process, the filling particles are made up from coarse to fine and their contents, and divided into four types of filling strata, and the drilled holes are stratified according to their thicknesses.
Filling a soil layer with stone blocks: the contents of the lump stones (d ≧ 200mm) and the crushed stones (60mm < d ≦ 200mm) are 15% -50%, and the content of the lump stones is greater than the content of the crushed stones. Mixing coarse and fine soil and clay.
Filling a soil layer with crushed stones: the contents of the lump stones (d ≧ 200mm) and the crushed stones (60mm < d ≦ 200mm) are 15% -50%, and the content of the crushed stones is greater than that of the lump stones. Mixing coarse and fine grains, powder and clay.
Thirdly, gravel filling: the content of gravel (2mm < d < 60mm) is 15-50%, and a small amount of stone, sand and clay are mixed.
Clay soil mixed gravel filling layer: soil with content of sticky particles (0.005mm < d < 0.0075mm) more than 50% and content of coarse particles (d ≧ 2mm) 25% -50%.
(2) Extra-heavy cone dynamic sounding (N)120) And (6) testing. In the range of sampling and wave speed testing hole edge spacing within 1.0m, adopting superheavy cone dynamic sounding (N)120) And (4) carrying out in-situ test, wherein the test depth is continuous test and penetrates through the compacted filling layer, and the hammering number carries out bidirectional correction on the drill rod and the hammering number.
(3) The shear strength index (c, phi) is determined by the field shear test. Adopting a flat pushing method, the shearing load is parallel to the shearing surface, and the shearing area is 1.0m2Height of 0.5m, and normal stresses of 150T, 300T, 450T and 600T are adopted according to 3 groups of tests of four rammed earth types. After the test is finished, the shear strength indexes ((c, phi) of each rammed filling soil layer are calculated, the shear strength indexes are used for determining the bearing capacity characteristic value of each filling soil layer, and the bearing capacity characteristic value is calculated by using a formula 5.2.5 in the national standard building foundation design Specification (GB 50007-2011).
fak＝Mbγb+Mdγmd+McC
In the formula: f. ofak-characteristic value of foundation bearing capacity (kpa) determined by shear strength index of the soil;
Mb、Md、Mc-a load factor;
gamma-the gravity of the soil below the basal floor (kN/m)3) Taking the floating gravity below the underground water level;
γmweighted average gravity (kN/m) of the soil above the base3) Taking the effective gravity of a soil layer below the underground water level;
d-base embedment depth (m);
b, the width (m) of the bottom surface of the foundation is taken as 6m when the width is larger than 6m, and is taken as 3m when the width is smaller than 3 m;
c-standard value of cohesive force (kpa) of soil in the depth range of one time of the width of the short side under the substrate.
The width b of the bottom surface of the foundation takes a value of 6, and when the bearing capacity of the foundation of the tamping (compacting) filling soil layer is calculated, the foundation embedding depth is considered according to 0, namely d takes a value of 0.
(4) Based on a large amount of data of the ultra-heavy dynamic sounding and on-site shearing test, the bearing capacity characteristic values and the deformation moduli of the four fill layers are determined according to the specifications of engineering geological handbook (fifth edition) and the like and engineering experience, and are detailed in table 1.
Table 1 shows the relationship between the characteristic values of the bearing capacity and the deformation modulus of four fill layers
(5) The table 1 can establish the ultra-heavy dynamic sounding (N120) and the bearing characteristic value (f) of four different filling soilsak) The corresponding relationship is shown in Table 2.
TABLE 2 Extra-heavy dynamic sounding (N120) and bearing characteristic values (f) of four different fillak) Corresponding relationship of
Analyzing the data by a scatter diagram, and obtaining a rammed (compacted) filling load-bearing characteristic value (f) by linear regression (as shown in figure 1)ak) Number of hammering of super-heavy dynamic sounding120(attack) relation equation (R)2Representing the reliability of the linear regression, the closer the value is to 1, the more reliable the regression formula):
filling a soil layer with rock blocks: f. ofak＝20+31N120
And (3) gravel filling layer: f. ofak＝25+25N120
Gravel filling layer: f. ofak＝30+23N120
Filling the cohesive soil mixed with gravel: f. ofak＝35+19N120。
(6) Meanwhile, the ultra-heavy dynamic sounding (N) of four different types of filling soil can be established120) The relationship with the modulus of deformation (E0) is detailed in Table 3.
TABLE 3 corresponding relationship between the super heavy dynamic sounding (N120) and the deformation modulus (E0) of four different filling soils
And the data are analyzed by a scatter diagram, and the deformation modulus (E) of the tamped (compacted) filling soil can be obtained by linear regression (as shown in figure 2)0) Number of hammering of super-heavy dynamic sounding120(attack) relation equation (R)2Representing the reliability of the linear regression, the closer the value is to 1, the more reliable the regression formula):
filling a soil layer with rock blocks: e0＝3.5+1.9N120
And (3) gravel filling layer: e0＝4.0+1.5N120
Gravel filling layer: e0＝4.5+1.3N120
Filling the cohesive soil mixed with gravel: e0＝5.0+1.0N120。
The invention is further explained by the following embodiment, the embodiment is a material strip site A-E of a steel stock harbor service raw material site, a filling layer on the upper part of the site is treated by a dynamic compaction foundation and is subjected to stacking loading during the use period of the material strips for many years, C-shaped material strips are planned to be built on the raw material strips due to the requirements of environmental protection upgrading and intelligent transformation, the C-shaped material strips are particularly sensitive to sedimentation and deformation, and the bearing characteristic value and the deformation modulus of a rammed (pressed) solid filling layer with the thickness of about 4m need to be provided for the design of the C-shaped material strip foundation. Because the construction period is short, a large amount of time and financial resources are consumed by utilizing the traditional load test and the field direct shear test, so that the method for determining the bearing capacity characteristic value and the deformation modulus of the tamped filling soil layer in geotechnical engineering investigation is utilized, drilling sampling is utilized to carry out particle test on the filling soil, the filling soil layer is divided into three categories of a rock filling soil layer, a gravel filling soil layer and a cohesive soil mixed gravel filling soil layer according to the particle component content and the particle size, an ultra-heavy dynamic sounding test is synchronously carried out, and the bearing capacity characteristic values and the deformation modulus of the three filling soil layers are calculated according to the actual measurement hammering number of the ultra-heavy dynamic sounding and a linear equation of the bearing capacity characteristic value and the deformation modulus of each filling soil layer, wherein the calculation results are as follows:
by using the method, the time is greatly saved, accurate and reliable data are timely provided for the design of the C-shaped material strips, and the favorable comment of an owner unit is obtained. In order to verify the reliability of data, a load test is carried out at the dynamic sounding point position at the later stage, and the load test adopts the area of 4m2The square steel pressing plate is loaded according to 1/8 grades with 2.4 times of estimated characteristic bearing capacity, the first-level load is applied according to 2 times of the graded load, the load test result is consistent with the table, and the reliability of the method is fully verified.
The above description is only one embodiment of the present invention, and the above described embodiment only expresses the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.
Claims (2)
1. A method for determining the bearing capacity characteristic value of a rammed/compacted fill is characterized by comprising the following specific steps:
(1) drilling and sampling the rammed/compacted fill layer on a construction site, combining the source characteristics of the rock-opening material formed by ramming/compacting and a foundation treatment process, and classifying the rammed/compacted fill layer according to different contents of the grain size of fill particles, wherein the classification is as follows:
a. filling a soil layer with rock blocks: wherein the total content of the lump stones with d being not less than 200mm and the crushed stones with d being less than 60mm and less than 200mm is 15-50%, the content of the lump stones is greater than the content of the crushed stones, and coarse grained soil, fine grained soil and cohesive soil are mixed;
b. and (3) gravel filling layer: wherein d is not less than 200mm lump stones and 60mm is not less than 60mm and less than 200mm broken stones, the total content of the broken stones is 15% -50%, the content of the broken stones is greater than the content of the lump stones, and coarse grained soil, fine grained soil, silt and clay are mixed;
c. gravel filling layer: wherein the content of gravel with the size of 2mm < d < 60mm is 15% -50%, and is mixed with lump stone, sand soil and clay soil;
d. clay-particle soil mixed gravel filling layer: wherein the content of sticky particles in the soil with the size of 0.005mm < d < 0.0075mm is more than 50%, and the content of coarse particles with the size of d > 2mm is 25% -50%;
(2) respectively carrying out on-site direct shear test on different rammed/compacted fill layers in the step (1), wherein the direct shear test adopts a flat push method, the shear load is parallel to the shear plane, and the shear area is 1.0m2The height is 0.5m, 3 groups of tests are carried out on each type of the block stone filling, the broken stone filling, the gravel filling and the clay-particle soil mixed gravel filling, and the normal stresses of the block stone filling, the broken stone filling, the gravel filling and the clay-particle soil mixed gravel filling are respectively 150T, 300T, 450T and 600T; obtaining the cohesive force c and the internal friction angle phi of the shear strength index soil of various fill layers by using the measured values, and calculating the bearing capacity characteristic value f of various fill layers by using the shear strength indexak(kPa), the calculation formula is as follows:
fak＝Mbγb+Mdγmd+McC
in the formula: f. ofak-characteristic value of foundation bearing capacity (kpa) determined by shear strength index of the soil;
Mb、Md、Mc-a load factor;
gamma-the gravity of the soil below the basal floor (kN/m)3) Taking the floating gravity below the underground water level;
γmweighted average gravity (kN/m) of the soil above the base3) Taking the effective gravity of a soil layer below the underground water level;
d-base embedment depth (m);
b, the width (m) of the bottom surface of the foundation is taken as 6m when the width is larger than 6m, and is taken as 3m when the width is smaller than 3 m;
c, a cohesive force standard value (kpa) of soil in a depth range which is one time of the width of the short side under the substrate;
the width b of the bottom surface of the foundation takes a value of 6, when the bearing capacity of the foundation of the ramming/compacting filling layer is calculated, the embedding depth of the foundation is considered according to 0, namely d takes a value of 0;
(3) in the step (2), within the range of the direct shearing test point distance of 1.0m, adopting extra-heavy cone dynamic sounding (N)120) Performing in-situ test with continuous test depth, penetrating the rammed/compacted filling layer, recording the hammering number of each filling layer, and performing ultra-heavy dynamic sounding (N) in each drill hole120) The measured hammering number corresponds to the rammed/compacted filling layers with different classified particle sizes, and a corresponding relation table of bearing capacity characteristic values of four types of filling layers and the overweight dynamic sounding hammering number is established;
(4) analyzing through a scatter diagram, and then obtaining the bearing capacity characteristic values (f) of the four types of filling layers through linear regressionak) Number of hammering of super-heavy dynamic sounding120The relation equation:
filling a soil layer with rock blocks: f. ofak＝20+31N120
And (3) gravel filling layer: f. ofak＝25+25N120
Gravel filling layer: f. ofak＝30+23N120
Clay-particle soil mixed gravel filling layer: f. ofak＝35+19N120；
When geotechnical engineering investigation work is carried out in the later stage, the bearing capacity characteristic value of the similar filling layer is directly calculated according to the equation according to the actually measured ultra-heavy dynamic sounding hammering number.
2. The method of determining a ram/compacted fill bearing characteristic value of claim 1 wherein: calculating the bearing capacity characteristic value f of various fill layers in the step (2)akThen, the deformation modulus E of the block stone filling, the broken stone filling, the gravel filling and the clay-soil mixed gravel filling is respectively calculated0Modulus of deformation E0According to the Hooke's law experience of solid materials, obtaining the characteristic value of the known bearing capacity correspondingly according to the prior standard parameter table, and establishing the extra-heavy dynamic sounding N120And modulus of deformation E0Analyzing the data in the corresponding relation table through a scatter diagram, and obtaining the deformation modulus E of different types of filling soil through linear regression0Number of hammering of super-heavy dynamic sounding120The relation equation is as follows:
filling a soil layer with rock blocks: e0＝3.5+1.9N120
And (3) gravel filling layer: e0＝4.0+1.5N120
Gravel filling layer: e0＝4.5+1.3N120
Clay-particle soil mixed gravel filling layer: e0＝5.0+1.0N120。
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