• Magazine of the Korean Society of Agricultural Engineers
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• v.29 no.2
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• pp.64-73
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• 1987

효과적인 모래의 다짐 방법으로 진동에 의한 방법이 널리 사용되고 있다. 이 연구의 목적은 모래의 진동 다짐시 영향을 주는 인자의 개별적인 효과를 분석하고 가 인자들이 복합되어 진동다짐에 주는 효과를 분석하는 것이다. 이 연구에서는 진동시간 가속도 과도화중 염수비 시료의 다짐전 밀도등을 변화시켜가며 진동테이블 위에서 제작된 시료를 다짐하였고 시험결과는 상대밀도의 변화애 의하여 분석하였다 진동다짐의 효과는 다짐가속도 진동수 및 모래의 정도에 따라 변하며 과도하중이나 진건은 비교적 적은 영향을 주는 인자였다. 가속도가 1g 보다 큰경우 다짐효과는 진동이 시작되는 초기에 발생하였고 그 후는 면밀하게 진동효과가 나타났다. 효과적인 다짐을 위하여는 최적가속도와 최고 과도하중의 선택이 중요하며 최적치보다 큰경우는 다짐의 효과가 감소한다. 건조된 모래와 포화된 모래 모두 같은 최적가속도에서 최대의 다짐효과를 나타냈다. 각 인자 즉 가속도 진동수 단위 중량 영수비, 균등계수, 유효압경, 과도하중, 및 진동시간등의 효과를 복합하여 진동다짐의 효과를 상대밀도의 변화로 나타낼경우$\Delta$DR=38.0∧0.14 의 관계를 얻었다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4C
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• pp.127-136
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• 2011

The settlement of a compaction plate resting on the surface of rubble-mound and subjected to a vibrating vertical load can be characterized by a transient amplitude and a plastic settlement. As long as the maximum imposed load does not exceed the bearing capacity of the rubble-mound, plastic settlement will approach an ultimate value and essentially steady-state vibration will ensue. For the settlement behavior by vibro-compaction, most laboratory experiments were conducted on laterally confined samples with loads over the full surface area or on samples placed on a vibrating table. In the field, the loads cover only a small fraction of the surface area. In this study, crushed stones are loaded with the same as field condition. According to the vibro-compaction experiments on crushed stone, it was found that approximately 90% of total settlement occur within 2 minutes and plastic settlement increases with increasing cyclic stress levels including static and dynamic stress. A compaction equation on which the number of load cycles, amplitude of plate, settlement, width of plate, and cyclic stress are related each other is proposed.

• Proceedings of the Korean Geotechical Society Conference
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• 1993.06a
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• pp.83-116
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• 1993

This article analyzed the dynamic compaction incuced vibration of man made waste landfill. General dynamic properties and compaction-condition-related dynamic properties were analyzed. from the results, it was turned out that the shear modulus G=17496-58320 t/m2, dannpln ratio D=14~58%, dominant frequency f=6-14Hz. Also, it was turned out that the propagation velocitis of low amplitude shear wave and compressive wave were increased as the number of impact increased, the relation between peak particle velocity, and impact distance was wpp=5.08.[D/r E]-1.4, the peak particle velocity was high at the lower part of the waste fill layer and the range of dynamically improved area was about 6-10m.

• International Journal of Highway Engineering
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• v.3 no.4 s.10
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• pp.127-136
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• 2001

To increase the structural integrity of concrete box culvert good compaction by the dynamic compaction roller with bi9 capacity is as effective as good backfill materials. It is needed for effective compaction that a compaction roller closes to concrete structure with high frequency. However structural distress of the culvert could be occur due to the excessive earth pressure by great dynamic compaction load. To investigate the characteristics of Induced stress by compaction, a box culvert was constructed with changing cushion materials and compaction methods. Two types of cushion material such as tire rubber chip and EPS(Expanded Polystyrene) were used as cushion panels and they are set on the culverts before backfill construction. Laboratory test result of cushion material says that the value of dynamic elastic modulus of rubber is lesser than that of EPS. On the other hand, material damping of rubber material is greater than that of EPS. In most case, dynamic compaction rollers with 10.5 ton weights were used and vibration frequency was applied 30Hz for the great compaction energy. This paper presents the main results on the characteristics of dynamic earth pressures during compaction. The amounts of induced dynamic pressures$(\Delta\sigma\;h)$ by compaction are affected with construction condition such as compaction frequency, depth of pressure cell, distance between roller and the wall of culvert and roller direction. Based on the measured values dynamic lateral pressure on the culverts, it could be said that orthogonal direction of roller to the length of culvert is more effective to compaction efficiency than parallel direction.

• Journal of the Korean Geotechnical Society
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• v.16 no.5
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• pp.45-54
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• 2000

경험적으로 방법에 의존해온 대형 진동햄머다짐의 영향심도를 평가하고자 수치해석적인 기법을 사용하였다. 수치해석적인 기법을 사용하였다. 수치해석에 사용한 프로그램은 범용 유한요소 해석프로그램인 ABAQUS이며, 인천 신공항 매립지에서 시험 시공한 대형 진동햄머다짐의 자료와 수치해석한 결과의 비교를 통해 검증하였다. 수치해성에 사용한 물성은 현장시험과 실내시험을통해 구하였으며 영향깊이는 지반이 동적 하중에 변형할 때 소산하는 소성변형율에너지량의 분포를 판정하였다. 수치해석결과 소성변형율에너지 소산량의 시간에 따른 변화로부터 다짐의 영향깊이 및 수평영향거리를 추정할 수 있었다. 소성변형율에너지 수렴시의 외부에너지를 Menard의 경험식에 적용할 경우 영향깊이를 판정할 수 있음을 알았다. 따라서 Menardtlr으로부터 영향깊이를 다짐하는데 필요한 최소한의 에너지를 구할수 있을 것으로 판단된다.

• Journal of the Korean GEO-environmental Society
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• v.23 no.8
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• pp.11-16
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• 2022

The compaction process using vibrating rollers in road construction is essential to increase soil stiffness in earthworks. Currently, there is no clear standard for the operation method of the compaction roller during compaction. Although simple quality inspection techniques have been developed, plate load test (PLT) and field density test (FDT) are the most frequently used test methods to evaluate the degree of compaction during road construction as the most frequently used quality inspection methods. However, both inspection methods are inefficient because they cannot perform quality inspection in all sections due to time and cost reasons. In this study, we analyzed how the operating conditions of vibrating rollers affect the compaction quality. An intelligent quality management system, which is a currently developed and commercialized technology, was used to obtain quality inspection results in all sections. As a result of the test, it was analyzed that the speed and vibration direction of the compaction roller had an effect on the compaction degree, and it was found that the compaction direction had no effect on the compaction degree.

• Proceedings of the Korean Geotechical Society Conference
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• 1993.06a
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• pp.55-72
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• 1993

Dynamic compaction may cause some demages to structures becasue it uses the impact energy of heavy weight with high drop height. This study measured and analyzed the vibrations at the (bnamic compaction site which was composed of man-made land fill. From the vibration analysis, it was found that the particle velocity and attenuation was greatest in longitudinal direction and smallest in transversal direction, the dominant frequency ranged from 7 Hz to 9 Hz and the structural damage could be prevented by reducing the drop height at the vicinity of the vibration sentialive structures. Also, the damage to the office equipment could be prevented by doing the dynamic compaction work curing closed-office hours.

• Journal of the Korean Geotechnical Society
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• v.16 no.5
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• pp.157-168
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• 2000

토류구조물의 안정문제로는 장단기적으로 정적인 경우와 동적인 경우, 그리고 지반의 동적 거동특성, 흙의 강도저하 등을 미리 파악하여 기술적인 대처를 할 필요가 있을 것이다. 본 연구에서는 실내 모형 실험을 통하여 구조물의 배면에 토성이 다른 일반모래, 표준모래, 점성토를 뒷채움하여 다짐없이 강사만 하고, 룰러다짐, 진동다짐을 하여 토피의 수평 진동거리를 길게, 짧게 그리고 중간으로 하여 강성벽체에 작요？는 수평토압에 대한 정적, 동적 특성을 규명하는 것이다. 모형 실험장치로는 실험대, 토조, 토압측정장치, 진동하중 발생장치, 진동측정장치, 강사기, 롤러 등을 설치하여 거리에 따른 병진운동으로 가속도와 수평토압, 수평토압계수, 전체토압, 토압의 작용점, 지진토압증분 증을 구하여, 실험결과와 기존 이론결과, 그리고 유한요소 해석결과와 비교 고찰하였다.

• International Journal of Highway Engineering
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• v.2 no.1
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• pp.147-156
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• 2000

Compaction is known to critically affect pavement performance. Due to its importance, a theoretical modelling of compacted density in the term of number of roller coverages is attempted by assuming compaction process essentially identical to pavement rutting. Excellent data fittings by the developed equation may prove the validation of assumptions made as well as justification of its use. According to the derived equation, a plot of density difference with respect to number of roller coverages in the logarithmic scale Produces a linear relationship. However, this linearity is turned out to be deviated by cooling effect, change of amplitude and frequency. Investigation of these three factors proposes a new generalized compaction density equation, which shows a promising future. By applying this general formula, the equations for the number of roller coverages required and the final compaction density obtained for a particular compaction project is derived first time in compaction research.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.292-309
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• 1983

This study is intended to find out the degree of compaction in field compaction, with soil type, the thickness of soil layer and the number of roller passing through the field density test and the field C. B. R. test by comparing vibration and non-vibration compactions. The results in this study are summarized as follows. 1. When the number of roller passing is few, it shows that the efficiency of the compaction by vibratory compaction is greater than that by non-vibratory compaction, the difference of the compaction ratio between vibratory and non-vibratory compaction is decreased according as the number of roller passing is more frequent. 2. Mechanizing on a large scale it is possible for a large equipment to be able to reach the point of A-1 compact ion method with three to five times of roller passing. To provide for mechanizing on a larger scale it is advisable to fix the standard by the D-2 compaction method. 3. As dry-density increases, the C. B. R. value increases, but the increasing ratio of C. B. R. value showed greater in vibrating compacting. 4. According as the number of roller passing increases, the increasing tendency of the C. B. R. Value is slow and the difference of the C. B. R. value between vibration and non-vibration compaction is large, the C. B. R. value showed greater about 20% in vibration compaction than in non-vibration compaction. 5. In C-5 soil type, with increasing the thickness of compaction, the degree of compaction is decreased. When the thickness of compaction is increased from 20cm to 30cm, the degree of compaction is decreased slowly, while the thickness of the compaction is increased from 30cm to 40cm the degree of compaction is decreased remarkably. Therefore it is advisable to compact the ground under the thickness of 30cm.