JP4358036B2 - Method for estimating rolling characteristics of construction materials - Google Patents

Description

The present invention relates to a method of estimating the rolling pressure characteristics of the construction material (N-ρ _d line).

  Conventionally, quality control methods in embankment work include (1) quality regulation method, (2) construction regulation method, and (3) construction method regulation method. The quality prescribing method (1) is a method of directly measuring the dry density and air porosity of the embankment and confirming that the standard value is satisfied. The construction regulation method of (2) and the construction regulation method of (3) are to investigate in advance the number of rolling times necessary to achieve standard values such as dry density and air porosity, and manage the number of rolling times. Is a kind of method to ensure quality.

  In the method (2), the running locus of the compacting machine is captured by GPS or the like, thereby ensuring that there is no shortage of rolling pressure (remaining stepping) throughout the construction site (see, for example, Patent Document 1). . In the method (3), the required rolling time is calculated from the construction area and the required number of rolling times, and it is confirmed that the actual rolling time recorded by a task meter or the like is longer than that. However, since the movement of the rolling machine cannot be specified, it cannot be guaranteed that there is no leftover.

Japanese Patent No. 3362833

  However, the method (1) is not suitable for rapid mass construction because the upper layer cannot be constructed during measurement of dry density, air porosity, and the like. Moreover, in large-scale embankment construction, it takes enormous labor, cost, and time to measure dry density and air porosity. Furthermore, when the layer thickness exceeds 20 to 30 cm, the commercially available RI instrument cannot measure the entire layer from the surface, and excavation is necessary to measure the depth.

  Therefore, the methods (2) and (3) for managing the quality by the number of rolling times are effective. However, in large-scale construction, there are a wide range of collection sites for the embankment material, so the quality of the embankment material (moisture content, particle size, mineral composition, particle shape, particle hardness, artificial or other contents of various mixtures) Etc.) may vary greatly during construction. In such a case, even if the required number of rollings set by carrying out test construction (on-site rolling test) at the start of the construction is satisfied, quality defects such as density occur in the embankment due to the quality fluctuation of the embankment material. Or the quality may be excessive and uneconomical. The above problem can be solved by revising the required number of rolling rolls every time the quality of the embankment material changes, but in order to do so, a rolling roll test must be additionally performed, which is a burden from the standpoint of site conditions, time, and costs. Is big.

The first invention performs an on-site rolling test on a standard material having a certain moisture content, and creates a first N-ρ _d line representing the relationship between the rolling frequency N and the dry density ρ _d at the moisture content. Step (a), obtaining a dry density at the water content ratio by an indoor tamping test with at least two kinds of work for the standard material, and the first N-ρ _d line And the step (c) of setting the number of on-site rolling compaction equivalent to the work amount from the dry density at the water content ratio, and the construction material, at the construction water content ratio by the indoor tamping test at the work amount. Step (d) of obtaining a dry density, and the construction material, using the dry density at the construction water content ratio and the number of on-site rolling pressures, the number N of rolling pressures and the drying density ρ _{d at the} construction water content ratio. The second N- a rolling pressure characteristic estimation method for construction materials, characterized by comprising a step (e) to create a [rho _d line.

In the first aspect of the invention, in step (a), the the standard material subjected to site compaction test, there the water content ratio W _{A (water} content ratio during the field compacting test; Nature water content ratio) drying and rolling pressure circuit number N in density creating a first N-[rho _d line representing the relationship between [rho _d. As the standard material, a material (filling material) that can be used at the time of the step (a) or a construction material (filling material) used in the step (c) is used. The acquisition of the water content ratio W _A, using a history test methods JIS like.

In step (b), the standard material, by performing the room compaction test at least two types of workload _{E c1, E c2,} dry density [rho _d11 in the water content ratio _{W A,} obtains the [rho _d21. For the tamping test method and the work amounts E _c1 and E _c2 , for example, a JIS tamping test method and the work amount determined thereto are used. When a construction material is used as the standard material, a W-ρ _d line representing the relationship between the water content ratio W and the dry density ρ _d at the work amounts E _c1 and E _c2 is created in step (b). Is desirable.

In step (c), a first N-[rho _d line created in step (a), the dry density [rho _d11 in the water content ratio _{W A} obtained in step (b), from [rho _d21 Prefecture, workload _{E c1,} The number of on-site rolling times N ₁ and N ₂ equivalent to E _c2 is set. That is, from the first N-ρ _d line, the number N of rolling _{pressures at} the dry density ρ _d11 , ρ _d21 is read and set as the number of on-site rolling times N ₁ , N ₂ .

In the step (d), dry densities ρ _d12 and ρ _d22 at a construction water content ratio W _B are obtained for the construction material by an indoor tamping test with work amounts E _c1 and E _c2 . When using the construction material as the standard material in the step (a), if the W-ρ _d line is created in the step (b), the construction moisture content W _B from the W-ρ _d line in the step (d) The dry density is read and set as dry densities ρ _d12 and ρ _d22 .

Step uses a construction material for the standard material (a), step (b) If you have not created a W-[rho _d curve in the case of not using the construction material for the standard material, the step (d) in performing compaction test, dry density [rho _d12 in construction water content ratio _{W B,} obtains the [rho _d22. The tamping test method and the work amounts E _c1 and E _c2 are the same as those in the step (b). In addition, when the construction material is not used as the standard material, W-ρ _d representing the relationship between the moisture content W and the dry density ρ _d at the work loads E _c1 and E _c2 in the step (d). It is desirable to create a curve.

In step (e), for the construction material, using the dry density ρ _d12 and ρ _d22 obtained in step (d) and the number of on-site rolling times N ₁ and N ₂ set in step (c), to create a second N-[rho _d line representing the relationship between the rolling pressure circuit number N and dry density [rho _d in the ratio W _B. Second N-[rho _d line shall pass through the two points _{(N 1, ρ d12),} (N 2, ρ d22).

To increase the accuracy of the second N-[rho _d line, to previously obtain the upper limit value [rho _dsat dry density in construction water content ratio _{W B} during step (e), in step _{(e), (N 1,} ρ d12 ) The second N-ρ _d line is obtained so that it passes through two points (N ₂ , ρ _d22 ) and approaches the asymptotic line ρ _d = ρ _dsat as the number of rolling operations N increases. _{Alternatively} , three or more kinds of work E _c1 , E _c2 , E _c3 ... _Are used in steps (a) to (d), and three or more points (N ₁ , ρ _d12 ) in step (e), (N ₂ , ρ _d22 ), (N ₃ , ρ _d32 )... _Are approximated by a least square method to obtain a second N-ρ _d line.

Subsequent steps (e), if the quality of the non-water content of the construction material in construction is and when changed, the quality of the non-water content is not changed, which changes the construction water content W _B, the step (d) The tamping test is performed again, the process (d) and the subsequent steps are repeated, and the necessary number of rolling times is reset. However, when the quality other than the moisture content does not change, if the W-ρ _d line of the construction material is created in the step (b) or the step (d), the new construction moisture content is determined from the W-ρ _d line. What is necessary is just to read the dry density of time and to repeat a process (d) and subsequent steps.

According to the present invention, even if the quality of the embankment material changes during construction, the relationship between the number N of rolling compaction and the dry density ρ _d is shown so that the necessary number of rolling compaction can be reasonably reset by a simple method. rolling pressure characteristic estimation method for construction materials capable of estimating the N-[rho _d line can provide.

  Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a flowchart showing the flow of the embankment construction method. As shown in FIG. 1, in this embodiment, prior construction 19 is performed using the standard material A before the embankment is constructed (step 113). In addition, a construction study 21 is performed using the construction material B.

In preliminary study 19, first, the standard material A, conducted situ compaction test, measures the water content ratio W _A during the test (step 101). As the standard material A, a fill material that can be used at the start of the preliminary study 19 is used. FIG. 2 is a diagram showing the relationship between the number of rollings N and the drying density ρ _d for the standard material A, where the horizontal axis represents the number of rollings N and the vertical axis represents the drying density ρ _d .

In step 101, an on-site rolling test, that is, test construction is performed with the same layer thickness and construction model as in the actual construction, and as shown in FIG. 2, a plurality of actual measurement values 1 (number of rolling times N, dry density ρ _d ) To get. In addition, to get the water content ratio W _A at the time of the field compaction test. The moisture content is measured using a test method such as JIS.

Next, the number of rolling times N-dry density ρ _d curve 3 (first N-ρ _d line) is obtained (step 102). In step 102, as shown in FIG. 2, the measured value 1 in the field compaction tested curve approximation, rolling seek pressure circuit number N- dry density [rho _d curve 3. It is said that the rolling frequency N-dry density ρ _d curve 3 can be satisfactorily approximated by a hyperbola of the form ρ _d = a + N / (b + c · N), for example. The coefficients a, b, and c are coefficients that vary depending on the embankment material quality other than the water content ratio, the construction method (layer thickness, construction model, etc.), and the like. In FIG. 2, the actual measurement value 1 is approximated by a curve, but the relationship between the number of rollings N and the drying density ρ _d may be represented by a broken line.

While performing steps 101 and 102, the standard material A is subjected to an indoor tamping test using two types of tamping work amounts E _c1 and E _c2 (step 103). For the tamping test, for example, a test method of JIS A-1210 is used.

The tamping work amount E _c is a work amount (kJ / m ³ ) given per unit volume, and two types of tamping work amounts E _c1 and E _c2 are, for example, E _c1 ≈550 kJ / m ³ , Let E _c2 ≈ 1100 kJ / m ³ . E _c indicates the energy given to the soil per unit volume, and using E _c = nmgh / V, using the total number of times of compaction n, the ramer mass m, the rammer fall height h, the gravitational acceleration g, and the container volume V. Calculated.

FIG. 3 is a diagram showing the relationship between the moisture content W and the dry density ρ _d for the standard material A, where the horizontal axis represents the moisture content W and the vertical axis represents the dry density ρ _d . In step 103, a tamping test is performed on the standard material A at a tamping work amount E _c1 , E _c2 , and a ground survey method published by the Geotechnical Society (1995) as necessary for the water content ratio and the obtained dry density. The gravel correction shown in the above is performed and converted to the moisture content and dry density at the on-site particle size. By step 103, as shown in FIG. 3, the water content ratio W at the tamping work amount E _c1 , the plurality of points 5a indicating the relationship between the drying density ρ _d , the water content ratio W at the tamping work amount E _c2 , and the drying density plurality of points 5b showing the relationship between [rho _d is obtained.

After step 103, water content ratio W- dry density [rho _d curve 7 (7a, 7b) seek (step 104). In step 104, as shown in FIG. 3, the plurality of points 5a and the plurality of points 5b acquired in step 103 are respectively approximated by curves, and the water content ratio W-dry density ρ _d curve 7a at the tamping work amount E _c1 is obtained. determining the moisture ratio W- dry density [rho _d curve 7b in compaction work of _{E c2.} Incidentally, FIG. 3 at point 5a, is the point 5b and curve approximation may represent the relationship between the water content ratio W and dry density [rho _d in a line.

Step 102, after the completion of step 104, the water content ratio _{W A} at site compaction test, estimates the compaction work of _{E c1, E c2} equivalent to the field inversion voltage dividing number _N 1, _{N 2} (step 105). In step 105, as shown in FIG. 3, dry density in the water content ratio W- dry density [rho _d curve 7a in compaction workload E _c1, water content ratio at the site compacting test W _{A (natural} water content ratio) Read _ρd11 . Further, the water content ratio W- dry density [rho _d curve 7b in compaction workload _{E c2,} reads the dry density [rho _d21 in water content ratio _{W A} at site compacting tests.

Further, as shown in FIG. 2, the number of on-site rolling times at which the drying densities ρ _d11 and ρ _d21 are read from the rolling pressure N-dry density ρ _d curve 3 is equivalent to the tamping work amounts E _c1 and E _c2. The on-site rolling times N ₁ and N ₂ are set. This site rolling pressure circuit number _N 1, _{N 2,} in the water content ratio _{W A} at site compaction test, the same dry density as by Indoor compaction tests at two compaction workload _{E c1, E c2 ρ d11} , Ρ _d21 represents the number of times of rolling required to achieve on-site. The number of rolling times N ₁ and N ₂ may not be an integer.

Next, the construction review 21 will be described. In the examination 21 during construction, first, an indoor tamping test is performed on the construction material B1 using two types of tamping work amounts E _c1 and E _c2 (step 106). In step 106, in the same manner as in step 103 of the preliminary study 19, an indoor tamping test is performed with two types of tamping work amounts E _c1 and E _c2 , and gravel correction is performed as necessary.

FIG. 4 is a diagram showing the relationship between the water content ratio W and the dry density ρ _d for the construction material B1, where the horizontal axis shows the water content ratio W and the vertical axis shows the dry density ρ _d . By step 106, as shown in FIG. 4, the water content ratio W at the on-site particle size at the work load E _c1 , a plurality of points 11a indicating the relationship between the dry density ρ _d , the water content ratio at the work load E _c2 W, a plurality of points 11b showing the relation between dry density [rho _d is obtained.

After step 106, water content ratio W- dry density [rho _d curve 13 (13a, 13b) obtaining a (step 107). In step 107, as shown in FIG. 4, 11a points obtained in step 106, respectively curve approximating the point 11b, the water content ratio in the compaction work of _{E c1} W- dry density [rho _d curves 13a, compactor work The water content ratio W-dry density ρ _d curve 13b at the amount E _c2 is determined.

In step 107, the zero air gap curve 15 may also be obtained. The zero air gap curve 15 is the theoretical upper limit of the dry density ρ _d , and ρ _d = ρw / (ρw / ρs + W / 100) using the water content ratio W (%), the water density ρw, and the soil particle density ρs. ).

Next, the construction water content ratio W _B1 at the time of construction is measured for the construction material B1 (step 108). The water content ratio is measured by the same method as in Step 101 of the preliminary study 19.

After completion of all the steps of the preliminary study 19 and the step 108 of the construction-time study 21, the estimated dry density values at the construction water content ratio W _B1 at the on-site rolling times N ₁ and N ₂ are ρ _d12 and ρ _d22. (Step 109). In step 109, the water content ratio W- dry density [rho _d curve 13a in compaction workload _{E c1,} reads the dry density [rho _d12 in construction water content ratio _{W B1} during construction. Further, the water content ratio W- dry density [rho _d curve 13b in compaction workload _{E c2,} reads the dry density [rho _d22 in construction water content ratio _{W B1} during construction.

In step 109, estimated in step 105, the relationship between the compaction work of _{E c1, E c2} and field inversion voltage dividing number _N 1, _{N 2} of the standard material A water content ratio _{W A} is the construction water content ratio _{W B1} It is considered that the construction material B1 also holds, and the estimated dry density values at the on-site rolling times N ₁ and N ₂ are the dry densities ρ _d12 and ρ _d22 at the tamping work amounts E _c1 and E _c2 .

This is because, in practice, the tamping energy per unit volume in the indoor tamping test is the weight weight W _R (kgf), the weight falling height H (cm), and the tamping force per layer. Using the number of times N _B , the number of layers N _L , and the container volume V, E _c = W _R · H · N _B · N _L / V = W _R · H · N _B / represented by volume per layer Therefore, if the construction method of the embankment (layer thickness, compaction construction model, running speed, compaction output, number of rollings) is constant, the energy received by the soil can be regarded as having no relation to the particle size.

After step 108, the upper limit value ρ _dsat of the dry density at the construction water content ratio W _B1 is _obtained (step 110). In step 110, the upper limit value ρ _dsat of the dry density at the construction water content ratio W _B1 at the time of construction is read from the zero air gap curve 15 (FIG. 4) obtained in step 107.

After the completion of Step 109 and Step 110, the number of rolling times N-dry density ρ _d curve 17 (second N-ρ _d line) of the construction material B1 at the site is obtained (Step 111). FIG. 5 is a diagram showing the relationship between the number of rolling compactions N and the drying density ρ _d for the construction material B1, where the horizontal axis represents the number of rolling compactions N and the vertical axis represents the drying density ρ _d .

In step 111, as shown in FIG. 5, the drying densities ρ _d12 and ρ _d22 at the on-site rolling times N ₁ and N ₂ estimated in step 109 and the upper limit value ρ _{dsat of} the drying density obtained in step 110 are obtained. from, it sets the rolling pressure circuit number N- dry density [rho _d curve 17 in construction water content ratio _{W B1} construction material B1. The rolling number N-dry density ρ _d curve 17 passes through two points (N ₁ , ρ _d12 ), (N ₂ , ρ _d22 ), and as the number of rolling times N increases, the asymptotic line ρ _d = ρ _dsat Get closer. The number of rolling times N-dry density ρ _d curve 17 can also be approximated by a hyperbola, similar to the number of rolling times N-dry density ρ _d curve 3 obtained in step 102. Moreover, you may represent the relationship between the rolling rolling frequency N and dry density (rho) _d with a broken line.

After estimating the rolling number N-dry density ρ _d curve 17 which is the rolling characteristic of the construction material as described above, the necessary number of rolling times at which the drying density ρ _d exceeds the standard value is set (step 112). ). Although the standard value varies depending on the construction, for example, when the standard value is expressed by 0.9ρ _dmax using the maximum value ρ _dmax of the dry density shown in FIG. 4, in step 112, as shown in FIG. The required number of rolling times satisfying the standard value 0.9ρ _dmax is read from the number N-dry density ρ _d curve 17.

  After completing step 112 and completing the examination 21 at the time of construction, the embankment is constructed (step 113). Then, it is determined whether or not the construction is completed (step 114).

  If it is not completed, the process proceeds to an arrow No, and it is determined whether it is necessary to review the quality other than the water content ratio of the construction material B1 (step 115). When the construction material B2 having a quality other than the moisture content is different from that of the construction material B1, the process proceeds to the Yes arrow and returns to Step 106, and the construction examination 21 is repeated for the construction material B2.

If it is not necessary to review the quality other than the water content ratio, the process proceeds to an arrow No and returns to step 108. When the construction water content ratio W _B2 measured in the second step 108 is equal to the previous construction water content ratio W _B1 , the rolling frequency N-dry density ρ _d curve 17 obtained in the previous step 111 can be used again. When the construction water content ratio W _B2 is different from the construction water content ratio W _B1 , Step 109 and subsequent steps are repeated. That is, the water content ratio W- dry density [rho _d curve 13 shown in FIG. 4, from zero air gap curve 15, dry density [rho _d in construction water content ratio _{W B2} definitive workload _{E c1, E c2,} the upper limit of the dry density [rho _dsat is acquired, and a new number of rolling times N-dry density ρ _d curve 17 is obtained.

The flowchart of FIG. 1 is applied when (layer thickness, compaction construction model, running speed, compaction output, number of rollings) is constant. When changing the construction method, the preliminary examination 19 including the on-site rolling pressure test (step 101 and step 102 of the preliminary examination 19) is performed again, and the on-site rolling times N ₁ and N ₂ are estimated again.

As described above, in this embodiment, the preliminary examination 19 is performed for a certain construction method, and the on-site rolling times N ₁ and N ₂ equivalent to the predetermined tamping work amounts E _c1 and E _c2 are set. When the quality of the construction material changes during construction, the number of rolling rolls is determined by repeating the compaction test and the moisture content measurement, or repeating the moisture content measurement, without repeating a large on-site rolling test. The N-ρ _d line showing the relationship with the dry density ρ _d can be estimated.

When performing the large-scale construction by the construction regulation method and the construction method regulation method for managing the quality by the number of rolling pressures by estimating the N-ρ _d line by the method of the present embodiment and setting the necessary number of rolling times, Even if the quality of the construction material fluctuates greatly during construction, it is possible to easily review the required number of rolling operations each time, and a cost advantage can be expected in the process.

Next, a second embodiment will be described. The second embodiment is a method in which Step 103 and Step 104 of the preliminary study 19 are most simplified, and the water content ratio W-dry density ρ _d curve 7 is not obtained. FIG. 6 is a diagram showing step 116 and step 117 instead of step 103 and step 104.

In the second embodiment, in the flowchart shown in FIG. 1, step 103, instead of step 104, the standard material A water content ratio W _A at site compacting test only two types of compaction work of E _c1 performs Me indoor compaction tests with _{E c2} (step 116), dry density [rho _d11 when the water content ratio _{W a,} compactor workload _{E c1, E c2,} obtains the [rho _d21 (step 117).

FIG. 7 is a diagram showing the relationship between the moisture content W and the dry density ρ _d for the standard material A, where the horizontal axis represents the moisture content W and the vertical axis represents the dry density ρ _d . In step 116 and step 117, tamping with a tamping work amount E _c1 and E _c2 for a standard material A having a water content ratio W _A (value before removal of gravel having a particle size exceeding the limit allowed in the tamping test). The test is performed, and the gravel correction is performed on the obtained dry density as necessary to convert it to the dry density at the in-situ particle size. The values of the tamping work amounts E _c1 and E _c2 , the tamping test, and the gravel correction method are the same as those in step 103 of the first embodiment.

Step 116, in step 117, as shown in FIG. 7, 23a that indicates the dry density [rho _d in compaction work load _{E c1} in the water content ratio _{W A,} relationship dry density [rho _d in compaction workload _{E c2} The point 23b which shows is obtained. When the procedure shown in FIG. 6 is adopted, in step 105, the number of on-site rolling _pressures corresponding to the drying densities _ρd11 and _ρd21 indicated by the points 23a and 23b in FIG. 7 is determined as the number of rolling times N-drying density shown in FIG. reading from ρ _d curve 3, and tamp amount of work _{E c1, E c2} equivalent to the field inversion voltage dividing the number _N 1, _{N 2.}

Next, a third embodiment will be described. Third embodiment is a method in which the most simplified step 108 from step 106 of construction during study 21, not seek water content ratio W- dry density [rho _d curve 13. FIG. 8 is a diagram showing steps 118 to 120 in place of steps 106 to 108.

In the third embodiment, instead of step 106 to step 108 in the flowchart shown in FIG. 1, first, the construction moisture content WB of the construction material _B is measured (step 118). The water content ratio is measured by the same method as in Step 101 of the preliminary study 19.

Next, the construction material B construction water content ratio _{W B} only, two performed Me indoor compaction test using a compaction workload _{E c1, E c2} (step 119), construction water content ratio _{W B,} compactor The dry densities ρ _d12 and ρ _d22 for the work amounts E _c1 and E _c2 are obtained (step 120).

FIG. 9 is a diagram showing the relationship between the water content ratio W and the dry density ρ _d for the construction material B, where the horizontal axis shows the water content ratio W and the vertical axis shows the dry density ρ _d . Step 119, in step 120, at the construction water content ratio W _B tamp workload for construction material B of _(the value before the removal of the gravel fraction limit or more particle size allowed by the compaction test) E _c1, E _c2 A tamping test is performed, and gravel correction is performed on the obtained dry density as necessary to convert it to a dry density at the on-site particle size. The values of the tamping work amounts E _c1 and E _c2 , the tamping test, and the gravel correction method are the same as those in the preliminary study 19 (step 103 in the first embodiment or step 116 in the second embodiment). .

In step 120 from step 118, dry density in FIG as shown in 9, 25a point indicating the dry density [rho _d in compaction work load _{E c1} in construction water content ratio _{W B} during construction, tamp workload _{E c2} [rho _d 25b point indicating the relationship is obtained. When the procedure shown in FIG. 8 is adopted, in step 109, as shown in FIG. 5, the estimated values of the dry density at the on-site rolling times N ₁ and N ₂ are shown by the points 25a and 25b in FIG. The densities are ρ _d12 and ρ _d22 .

In the third embodiment, after step 114, the process returns to step 118 without performing step 115. When the construction water content ratio W _B2 measured in the second step 118 is equal to the previous construction water content ratio W _B1 , the dry densities ρ _d12 and ρ _d22 obtained in the previous step 120 can be used again in the step 109. If the construction water content ratio W _B2 is different from the construction water content ratio W _B1 , step 119 and step 120 are repeated and the process proceeds to step 109.

Next, a fourth embodiment will be described. Fourth embodiment is a method in which the most simplified step 111 from step 109 of construction during study 21, not determined the upper limit value [rho _dsat the dry density of the construction material B in construction the water content ratio W _B. FIG. 10 is a diagram showing the relationship between the number of rolling compactions N and the drying density ρ _d for the construction material B1, where the horizontal axis represents the number of rolling compactions N and the vertical axis represents the drying density ρ _d .

In the fourth embodiment, step 110 is omitted in the flowchart shown in FIG. Then, as the step corresponding to step 111, as shown in FIG. 10, 27a that represents the dry density [rho _d when the field inversion voltage dividing number _N 1, _{N 2} estimated in step 109, to pass through the point 27b The number of rolling times N-dry density ρ _d line 31 is obtained. In step 112, the rolling pressure circuit number N- dry density [rho _d line 31 shown in FIG. 10, dry density [rho _d reads necessary rolling pressure circuit number to meet the specifications.

Even when the second to fourth embodiments are used alone or in combination, as in the first embodiment, a predetermined examination work 19 is performed for a certain construction method to obtain a predetermined tamping work amount E _c1 , By setting the number of on-site rolling pressures N ₁ and N ₂ equivalent to E _c2 , when the quality of the construction material changes during construction, a large-scale on-site rolling test is not repeated and a tamping test is performed. N-ρ _d line indicating the relationship between the number N of rolling compaction and the dry density ρ _d can be estimated by repeating the measurement of the water content ratio or the repetition of the water content ratio measurement.

  As mentioned above, although preferred embodiment of the estimation method of the rolling characteristic of the construction material concerning this invention was described referring FIGS. 1-10, this invention is not limited to this example. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

For example, in the preliminary study 19, the construction material B1 may be used as the standard material A of the preliminary study 19. In this case, in the methods described in the first to fourth embodiments, the work for obtaining the dry densities ρ _d11 and ρ _d21 at the time of the tamping work amounts E _c1 and E _{c2 in} the preliminary examination 19 (FIG. 1). Step 103 and Step 104 shown in FIG. 6 or Step 116 and Step 117) shown in FIG. 6 are omitted.

Then, as shown by the dotted line 9, the operation of step 105 is performed using the number of rolling N-dry density ρ _d curve 3 obtained in step 102 and the water content ratio W-dry density ρ _d curve 13 obtained in step 107. I do. The operation of Step 105 is performed using the number of rolling times N-dry density ρ _d curve 3 obtained in Step 102 and the dry densities ρ _d12 and ρ _d22 obtained in Step 120 (FIG. 8).

Moreover, the rolling in order to improve the accuracy of the pressure circuit number N- dry density [rho _d relationships, for the standard material A and construction materials B, 3 or more compaction workload _{E c1, E c2, E c3} ... ( e.g., E ^{_{c1 ≒ 550kJ / m 3, E}} c2 ≒ 1100kJ / m 3, E and _c3 ≒ _2500kJ / ^{m 3)} in may be performed Me indoor compaction test. In this case, in the step corresponding to step 105, the number of on-site rolling pressures N ₁ , N ₂ , N ₃ ... Equivalent to each tamping work amount is estimated, and in the step corresponding to step 109, the on-site rolling pressure number N _1. , N ₂ , N ₃ ..., _And after estimating the dry density ρ _d12 , ρ _d22 , ρ _d32 ..., Three or more points (N ₁ , ρ _d12 ), (N ₂ ) in a step corresponding to step 111. , Ρ _d22 ), (N ₃ , ρ _d32 )... _Are approximated by a least square method or the like to obtain the number of rolling times N-dry density ρ _d curve 17. The reliability of the rolling compaction number N-dry density ρ _d line 31 shown in the fourth embodiment by performing the indoor compaction test with three or more types of compaction work E _c1 , E _c2 , E _c3 . Will improve.

Furthermore, in this embodiment, if the construction method of the embankment (layer thickness, compaction construction model, running speed, compaction output, number of rollings) is constant, the energy received by the soil is considered to be unrelated to the particle size, While the pre-study 19 obtained in relation to a predetermined compaction workload E _c and the field inversion voltage dividing number N of the standard material a was directly fitted to the construction material B, and construction time study 21, optionally You may correct | amend this relationship.

Flow chart showing the flow of the embankment construction method The figure which shows the relationship between the rolling frequency N and dry density (rho) _d about the standard material A The figure which shows the relationship between the moisture content W and dry density (rho) _d about the standard material A The figure which shows the relationship between the moisture content W and dry density (rho) _d about construction material B1 The figure which shows the relationship between the rolling frequency | count N and dry density (rho) _d about construction material B1. The figure which shows step 116 and step 117 which replace step 103 and step 104 The figure which shows the relationship between the moisture content W and dry density (rho) _d about the standard material A The figure which shows step 118 to step 120 which replaces step 106 to step 108 For construction materials B, fig showing the relationship between the water content ratio W and dry density [rho _d The figure which shows the relationship between the rolling compaction frequency N and dry density (rho) _d about construction material B1.

Explanation of symbols

3, 17 ............ Number of times of rolling N-dry density ρ _d curve 7, 7a, 7b, 13, 13a, 13b ... water content W-dry density ρ _d curve 15 ....... zero air gap curve 19 ... ... Preliminary examination 21 ... Construction examination 31 ......... Number of rolling N-dry density ρ _d line

Claims (3)

A step (a) of conducting a field rolling test on a standard material having a certain water content to create a first N-ρ _d line representing the relationship between the number N of rolling times and the dry density ρ _d at the water content; ,
Step (b) for obtaining the dry density at the moisture content by an indoor compaction test with at least two kinds of work for the standard material;
A step (c) of setting the number of on-site rolling pressures equivalent to the work amount from the first N-ρ _d line and the dry density at the water content ratio;
For the construction material, the step (d) of obtaining the dry density at the construction moisture content by the indoor compaction test at the work amount,
About the said construction material, 2nd N- (rho) showing the relationship between the rolling density N in the said construction moisture content, and dry density (rho) _d using the dry density in the said construction moisture content, and the said number of on-site rolling pressures. a step (e) of creating a _d- line;
A method for estimating a rolling property of a construction material, comprising: In the step (e), when creating the second N-[rho _d line, the dry density of the working water content ratio, in addition to the said site rolling pressure circuit number, maximum dry density in the working water content ratio The method for estimating rolling characteristics of a construction material according to claim 1, wherein a value is used. The construction material is subjected to an indoor tamping test with the at least two kinds of work, and a W-ρ _d line representing a relationship between the water content ratio W and the dry density ρ _d is created. Item 2. A method for estimating the rolling characteristics of the construction material according to Item 1.

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