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A mechanical model of a metal nanopowder compaction is proposed. It takes into account the change in the shape of nanoparticles during mutual indentation, the action of surface tension, elastic stresses and plastic deformation of particles. The plastic deformation is the key point of compaction; the dislocation approach is used to incorporate the plasticity into the model. The model considers the stage of free relaxation, when the nanoparticles are mutually attracted due to the surface tension and mutually repulsed due to the elastic stresses, and the stage of compaction, when the interplay between elastic deformation and plasticity defines the mechanical response of the powder. The model provides a kinetic form of the constitutive equations for nanopowder and is intended for use in macroscopic modeling of the shock-wave processes in the calculation of installations for dynamic compaction of nanopowders to describe the local mechanical reaction and estimate the degree of compaction in each finite element. Molecular dynamics (MD) simulations of the dynamic compaction of Al nanopowders with particle diameters in the range of 6–30 nm are carried out. Comparison with the results of MD shows that the proposed model adequately describes both the relaxation stage and the powder compression stage. The effects of temperature, strain rate and nanoparticles piling are considered.

Ground improvement was required for construction of the Jaber Al Ahmed New City located about 25 km west of Kuwait City, Kuwait. Loose to medium poorly graded sands, and silty sands extended from ground level to a depth ranging from 5m to 9m. Dynamic compaction was employed, as an economic method, to increase the soil bearing capacity and reduce its compressibility for foundation design and construction. The testing program included borings and sampling, Standard Penetration Tests, Cone Penetration Tests and Pressuremeter Tests before and after dynamic compaction. The area covered in this study is about 31415m2. The results indicated significant ground improvement, and satisfaction of the specified acceptance criteria resulting in an allowable soil pressure, for shallow foundation design, equal to or exceeding 300 kN/m2.

A comprehensive series of tests was performed to investigate the effects of the in-situ structure and sample preparation technique on the compression behaviour of a shallow young alluvial silty soil. Two different particle size distributions were investigated by testing intact, compacted, and slurry samples in an oedometer. The compression of the slurry samples, created at different initial water contents, gave a unique intrinsic compression line for one of the two distributions. This was used as a reference for analysing the effects of the structure of the compacted and intact specimens. The compacted samples were prepared by means of static and dynamic compaction in one or more layers with vertical holes simulating those created by plant roots in natural samples. The results showed that a unique normal compression line is defined regardless of the number of layers or the number of holes, with a clear effect of the structure when compared to the slurry samples. The significant effects of the in-situ structure of the intact samples were observed even at high stress levels. An important finding was the non-uniqueness of the compression line for the second distribution. For the case of the slurry samples, the compression lines remained parallel to each other even at high stress levels, whereas a unique line was found for the compacted samples. These results are contrary to those often given in the literature, namely, that the sample preparation technique can create very robust initial structures resulting in a mode of behaviour that has been called “transitional”. The research also emphasises how the quantification of the natural structure is critically dependent on the way in which the intrinsic samples are prepared.

Dynamic compaction (DC) has been widely used for a variety of soil types and conditions in coastal area. However, as the ground water table is near the ground surface, a significant increase of pore water pressure is noticed after each impact, which results in local liquefaction and limits further drop effect. Consequently, to obtain effective compaction effects on saturated soils, it is essential for the evaluation of the liquefaction responses of soil medium caused by DC to determine the time delay between the drops and prevent ‘rubbery soil’. In this study, a numerical investigation on the liquefaction responses of saturated granular soils during DC is carried out using a coupled hydro-mechanical model. The developed model considers all the stages of DC involved in impact stage and consolidation stage. A new cap model for simulations of high strain rate behaviors of soils under DC is incorporated in the coupled hydro-mechanical model. Verification of the proposed model is performed against the previous test data and analytical result. Then, a series of parametric studies have been performed to examine the effects of the tamping energy level, hammer radius and permeability on liquefaction responses of saturated granular soils at several stages of DC. The numerical results demonstrate that the dimension of liquefaction zone is driven by the tamping energy level rather than the permeability, and strain rate has a significant effect on soil responses in DC.

Rolling dynamic compaction (RDC), which employs non-circular module towed behind a tractor, is an innovative soil compaction method that has proven to be successful in many ground improvement applications. RDC involves repeatedly delivering high-energy impact blows onto the ground surface, which improves soil density and thus soil strength and stiffness. However, there exists a lack of methods to predict the effectiveness of RDC in different ground conditions, which has become a major obstacle to its adoption. For this, in this context, a prediction model is developed based on linear genetic programming (LGP), which is one of the common approaches in application of artificial intelligence for nonlinear forecasting. The model is based on in situ density-related data in terms of dynamic cone penetrometer (DCP) results obtained from several projects that have employed the 4-sided, 8-t impact roller (BH-1300). It is shown that the model is accurate and reliable over a range of soil types. Furthermore, a series of parametric studies confirms its robustness in generalizing data. In addition, the results of the comparative study indicate that the optimal LGP model has a better predictive performance than the existing artificial neural network (ANN) model developed earlier by the authors. Keywords: Ground improvement, Rolling dynamic compaction (RDC), Linear genetic programming (LGP), Dynamic cone penetrometer (DCP) test

The dynamic compaction method is one of the most optimal technics in gravelly soil backfill projects. However, the basic mechanical characteristics of gravelly soils and mechanisms of dynamic compaction have not yet been precisely determined. In this study, by taking the advantage of large-scale triaxial tests, it could be seen that gravelly soils did not present strain-hardening phenomenon like other conventional soils. Additionally, the particular behaviors of gravelly soils, i.e., increase in cohesion and decrease in the internal friction angle, were determined from grain crushing tests and large-scale direct shear tests. On this basis, a modified constitutive model was established and programmed in FLAC3D under the framework of the Mohr–Coulomb criterion. Compared to a similarity simulation test, a more accurate constitutive model considering the kinematic hardening effect was developed. Finally, a 3D model was built, where the proposed modified constitutive model and numerical parameters led to a satisfactory optimized analysis of gravelly soil projects.

In the study, Si3N4-Al2O3-Y2O3 samples were obtained in two stages. In the first stage, the materials were compacted using different methods: Isostatic Pressing, UHP (Ultra High Pressure), and SC (Shock Compaction). In the second stage, the green body samples obtained were sintered using the free sintering method. Powder mixtures, in wt%, 88 Si3N4 - 6 Al2O3 - 6Y2O3, were based on commercial nano - and micropowders. The parameters of green bodies compaction and sintering processes were optimised using the criteria of highest density, hardness, and Young's modulus. When compared to theoretical density values, the density of green body samples was 58% for the Isostatic Pressing and 82% for UHP and Shock Compaction. The Vickers hardness was measured only for Shock Compacted green body samples and was ~10.8–14 GPa depending on the applied load during the measurement. The largest changes in lattice constant parameters were measured for the Y2O3 phase for the dynamic compaction method (a = 0.02% - 2.26%). The highest relative density was measured for materials which were compacted by UHP method and subsequently free sintered (95%). Young's modulus for UHP and Isostatic green body free sintered samples was 284 GPa and 241 GPa, respectively. The hardness values of samples after free sintering were as follows: 11.7GPa for Isostatic, 14.8 GPa for UHP, and 17.6 GPa for Shock Compaction samples.

This paper presents findings of a case study on the effect of dynamic compaction (DC) on liquefaction potential. The effect of DC is observed in two aspects: the increase in soil strength and the reduction in the variation of soil strength. The effect on the reduction of liquefaction potential through the increase in soil strength is well recognized but the benefit of DC through the reduction in the variation of soil strength is seldom reported. To recognize this benefit, the liquefaction potential is expressed herein in terms of liquefaction probability, as the analysis of the liquefaction probability necessitates the consideration of the coefficient of variation of key soil parameters, which can be captured in a DC project. The above concept is illustrated through a case study of a site where CPTs were conducted before and after DC and where liquefaction manifestation was observed in the 1999 Chi-Chi earthquake. The results of the analysis of these CPTs for liquefaction potential at the site before and after DC are reported. The implication of this study is significant in engineering practice; for example, it provides a basis for risk-based or performance-based design of ground improvement to mitigate the liquefaction hazards. The effect and benefit of ground improvement through the reduction in the variation of soil strength is a topic that is worthy of further studies.

In the present work functional properties of new, co-processed excipients, Pharmaburst (R) 500, Parteck (R) ODT, Ludiflash (R) and Disintequikn (TM) ODT, intended for direct compression of orally disintegrating tablets (ODTs), were investigated based on dynamic compaction analysis and percolation theory. Tablet disintegration time and mechanical properties have been recognized as critical quality attributes (CQAs) which should be optimized through pharmaceutical development. According to the obtained results, in order to achieve adequate mechanical resistance, excipients exhibiting high compactibility and tabletability are required, while, on the contrary, high porosity excipients with higher extent of elastic deformations, average tabletability and compactibility are necessary to obtain fast tablet disintegration. The results obtained in this study indicate that the most important excipient properties affecting tablet CQAs are porosity, mechanism of consolidation, compactibility and tabletability. Pharmaburst (R) 500, excipient with the highest elastic recovery, the lowest relative density, average compactibility and tabletability, and remarkably high dilution capacity (69.6% w/w of caffeine or 49.1% w/w of ibuprofen) exhibited favourable performance for ODT direct compression. Dynamic compaction analysis and percolation theory proved to be useful tools which can contribute to identification of the most important excipient functional properties influencing critical quality attributes of the prepared ODTs.

During dynamic compaction , frequent heavy load unloading impacts are the main reasons for crane structural damage. To address this problem, a new method to reduce the unloading impact for a crane is discussed. Firstly, through the energy method, an expression for the energy consumption of the unloader that has been ignored before is established and a mathematical model describing the key parameters of the unloader is obtained. Secondly, a force controlled unloader is designed to convert the pulling force control of the wire rope that suspends the heavy hammer into its own hydraulic control. Thirdly, a rigid-flexible coupling model of a crawler crane used for dynamic compaction is built to predict the relationship between the unloading time and the dynamic response. Finally, a new unloader that slowly releases heavy hammer in the air under gravity has been developed and the experimental result proves the feasibility of flexible unloader.

Compaction technology has been developed over the past three decades. However, the absence of an effective model that can rapidly and accurately simulate the compaction process limits the further development of compaction technology. In this paper, we propose a vibration compaction process model to simulate the compaction of rockfill materials. A viscoelastic-plastic dynamic compaction deformation formula for rockfill materials was proposed and, considering the horizontal movement of the roller, this formula was utilized for simulating pass-by-pass compaction by dividing the rockfill materials into equal-width blocks. Furthermore, an inversion method based on neural networks was proposed to determine the model parameters of real-world rockfill materials through field test results. Then, the effects of number of roller passes and vibration frequency were analyzed. The experimental results verified that the proposed model could effectively simulate the roller-soil interaction and rockfill material deformation characteristics and could thus provide a theoretical basis for intelligent compaction.

Rolling dynamic compaction (RDC) is a ground improvement technique, which involves towing a non-circular module behind a tractor to achieve soil compaction. When compared against conventional static and vibratory compaction techniques, RDC is capable of compacting thicker layers of soil and at a faster operating speed. This study validates the developed numerical scale model against a field study using the full-size RDC module. Numerical results were compared with the field data in four aspects namely, displacements at the ground surface, and at depths of 0.7 and 1.1 m, pressures at 0.7 and 1.1 m depths, energy delivered by the RDC module into the underlying soil, and the depth of improvement. It is concluded that, numerical results are in good agreement with the field data. This paper also proposes that pressure results are an imperfect indicator to assess the optimum number of RDC passes, whereas, ground settlement is recommended since it better reflects ground improvement due to RDC and it has a clear relationship with the number of passes.

Electrical resistivity tomography, ERT, is a geophysical method that is used to image subsurface geomaterials for various geological, environmental and geotechnical engineering problems. The success of ERT depends on the availability of a robust electrical resistivity model of soils that is able to characterise the different type of soils using its electrical resistivity measurements. The aim of this paper is to present an electrical resistivity/conductivity model for isotropic saturated sand/clay mixture that considers the effects of sand content, and surface conduction of clay content. The proposed model is formulated using a modified series-parallel mixing model theory which uses phase-volumetric and surface conduction model parameters. The phase-volumetric parmeters describe the configuration of the different soil/water phases in a representative soil unit cell which includes solid soil particles, free water, diffuse double layer (DDL) water. The surface conduction model parameters are used to describe the volume fraction of DDL water in the unit cell, and its electrical conductivity compared to the electrical conductivity of free water. Simple test methods are used in this study to determine the proposed model parameters. Laboratory experimental programme was also conducted in this study to validate the proposed model. Two types of clays, namely, kaolin and bentonite, and one type of clean sand were used to constitute five different sand/clay and clay/clay mixtures. Dynamic compaction method using Standard Proctor tools was used to constitute the testing samples. The electrical conductivities of different reconstituted soil samples were measured and compared with the proposed model predictions, and a good agreement was achieved. The small differences between the model predictions and the experimental measurements could be attributed to the slight deviation of the laboratory test samples from the model assumptions, which require the soil sample to fulfil fully saturated and electrical isotropy conditions.

The reuse of coarse aggregate (CA) on clay-based materials is a sustainable and cost effective solution to minimize the extraction of natural farmland resources and reinforce the mechanical behaviour of impervious materials. However, limited knowledge is available regarding the compactability and permeability of CA-clay mixtures and their intrinsic connections. This study reports the results of a series of modified dynamic compaction tests and triaxial permeability tests performed on impervious clay materials reinforced with various contents of CA. Results demonstrate that compaction behaviour of CA-clay mixtures changes significantly with coarse aggregate content (Cg). A peak value of global maximum dry density is achieved at Cg = 70%, while the fine clay matrix is compacted to its densest state when Cg

The aim of this paper is to provide further understanding of the mechanical behavior of soils when subjected to high-pressure and high-rate loadings. To this end, finite-element (FE) analyses of dynamic compaction and penetration events were conducted using the advanced elastic/plastic soil model of Lade (1977) which was extrapolated to large pressures and implemented into the FE framework. To ensure improved accuracy of the results for conditions involving loading/unloading and stress path changes, an implicit integration scheme was adopted. The simulation results for dynamic densification show that the initial precompaction of the material has a strong influence on both the wave speed and the shape of the wave front. As concerns the initiation of penetration, the simulation results indicate that for the same material, the inception and nature of the localization bands are also strongly dependent on the level of precompaction of the target material. Namely, for a low precompaction level, upon impact multiple bands develop whereas for a larger initial precompaction level, a primary localization band develops.

Analytical and numerical analyses are carried out in order to reveal the importance of the cellular materials topology for their dynamic compaction. The aim is to distinguish between the deformation and energy absorption mechanisms of materials which exhibit local structural softening, such as out-of-plane loaded honeycomb, and materials with local structural hardening (foam). It is shown that the dynamic out-of-plane compaction of honeycombs does not obey the law of shock wave propagation and a new phenomenological model of the velocity attenuation is proposed. It is revealed that the absorbed energy by the honeycomb is proportional to the area under the dynamic stress-strain curve, which is defined by the foil material properties, in contrast to the shock-wave propagation model where the absorbed energy is proportional to the area under the shock chord. Comparisons with the predictions of the Rigid Perfectly-Plastic Locking (RPPL) model, which approximates well the average quasi-static stress-strain characteristic of a honeycomb, are discussed. Special attention is given to the effects of neglecting the honeycomb topology on their response to impact loading. Finite element simulations are carried out to verify the proposed theoretical model revealing the major factors which influence the dynamic response of out-of-plane loaded honeycombs to high velocity impact.

Preloading consolidation with drains (PCD) and dynamic compaction (DC) are often combined to improve the ground condition. A novel method of modeling PCD and DC in centrifuge is developed in this study. 3D printing technique is used to greatly improve the manufacturing precision and simulation ability of sand drains. A loading container, which allows adding sand in it stage by stage, is well designed to achieve uniform surface loading. Based on strong magnet and reliable mechanical principle, a novel device for modeling dynamic compaction is developed, which can realize continuous tamping in centrifuge to a certain extent. An example test using dredged soil sampled from Putian Port, Fujian Province, China, was conducted to validate the performance of the method, including self-weight consolidation, four-stage preloading with drains, and dynamic compaction. The present method performed well to simulate the whole process of pretreating the dredged soil. The surface settlement, changes in excess pore pressure and effective stress, number of drops, crater depth, improvement depth by DC were reasonably predicted. Significant surface settlement and crater depth were observed during the preloading consolidation and dynamic compaction, respectively, indicating that the compressibility of the dredged soil was rather large. Spacing of sand drains behaved to be more effective than the length. The vertical distributions of water content, excess pore pressure, and effective stress revealed that the degree of consolidation decreased with depth, since the drainage condition in the upper part was better. The present method will contribute to a better understanding of PCD and DC, and is promising to be used for the design and evaluation of the current ground improvement methods.

Rolling dynamic compaction (RDC), which involves the towing of a noncircular module, is now widespread and accepted among many other soil compaction methods. However, to date, there is no accurate method for reliable prediction of the densification of soil and the extent of ground improvement by means of RDC. This study presents the application of artificial neural networks (ANNs) for a priori prediction of the effectiveness of RDC. The models are trained with in situ dynamic cone penetration (DCP) test data obtained from previous civil projects associated with the 4-sided impact roller. The predictions from the ANN models are in good agreement with the measured field data, as indicated by the model correlation coefficient of approximately 0.8. It is concluded that the ANN models developed in this study can be successfully employed to provide more accurate prediction of the performance of the RDC on a range of soil types.

Dynamic impact loading may cause gradual crushing of soil grains, especially when soil grains are characterised by weak strength or when the geologic history of the soil has influenced on material fatigue. The aim of the work is to identify the soil crushability during dynamic compaction, as well as the effect of a gradual grain crumbling on changes of the maximum dry density and the uniformity coefficient. All tests were performed for genetically different non-cohesive soils from various Polish areas. In Pleistocene river sands and in the sea sands – repeated compaction does not improve the coefficient of uniformity and does not result in significant changes in the maximum dry density. In the river sands from Holocene alluvial deposits, multiple compaction causes a significant increase in value of ρ d max . In glaciofluvial sands and gravel multiple compaction increases the maximum dry density and uniformity coefficient of compacted soil. The monomineralic soils was characterised by values of C U C U ≥ 3.0.

A numerical investigation into the performance of ground deformation due to dynamic compaction (DC), and a developed method of estimating ground deformation of granular soils caused by DC are presented. Firstly, a 2D numerical model is created in LS-DYNA and the result is verified by variables measured in a real field case using DC treatment. A simplified model for describing ground deformation is presented. Five deformation variables, δ v m , d δ v =0 , d δ u m , δ u m , d δ u =0.01% W t H , are defined to describe characteristics of ground surface deformation. An extensive parametric study is then conducted to investigate the effect of each parameter on the five deformation variables. Finally, based on the results obtained, a forecast model is produced to describe ground deformation under DC. The applicability of the proposed procedure is then illustrated by comparing its predictions with a case of DC applied in the field. The results of this comparison indicate that the predictions using the developed method are reasonably realistic. This suggested method can provide some easy and convenient guidelines to determine ground deformation of granular soils due to dynamic compaction.

Assessing liquefaction potential, in situ screening using cone penetration resistance, and liquefaction-remediation of non-plastic silty soils are difficult problems. Presence of silt particles among the sand grains in silty soils alter the moduli, shear strength, and flow characteristics of silty soils compared to clean host sand at the same global void ratio. Cyclic resistance (CRR) and normalized cone penetration resistance (qc1N) are each affected by silt content in a different way. Therefore, a unique correlation between cyclic resistance and cone resistance is not possible for sands and silty sands. Likewise, the response of silty soils subjected to traditional deep dynamic compaction (DC) and vibro-stone column (SC) densification techniques is influenced by the presence of silt particles, compared to the response in sand. Silty soils require drainage-modifications to make them amenable for dynamic densification techniques. The first part of this paper addresses the effects of silt content on cyclic resistance CRR, hydraulic conductivity k, and coefficient of consolidation Cv of silty soils compared to clean sand. The second part of the paper assesses the effectiveness of equivalent intergranular void ratio (ec)eq concept to approximately account for the effects of silt content on CRR. The third part of the paper explores the combined effects of silt content (viz effects of (ec)eq, k, and Cv) on qc1N using laboratory model cone tests and preliminary numerical simulation experiments. A possible inter-relationship between qc1N, CRR, accommodating the different degrees of influence of (ec)eq, k, and Cv on qc1N and CRR, is discussed. The fourth part of the paper focuses on the detrimental effects of silt content on the effectiveness of DC and SC techniques to densify silty soils for liquefaction-mitigation. Finally, the effectiveness of supplemental wick drains to aid drainage and facilitate densification and liquefaction mitigation of silty sands using DC and SC techniques is discussed.

This paper presents the FEM-SPH coupling method for the analysis of large deformation problems caused by dynamic compaction (DC). A 3D FEM-SPH coupling model was established in LS-DYNA to simulate the dynamic compaction process. Moreover, DC operation was also simulated separately by the traditional FEM and pure SPH in the same condition with that by the FEM-SPH coupling method. After comparing the results obtained from three simulations with data measured in field test, it was found that the FEM-SPH coupling model can be a useful tool with higher efficiency and accuracy for analysis of the large deformation problem in DC. Then the parametric analyses were performed in the proposed model to evaluate their influences on the effectiveness of compaction for ground soils. The results indicate that the splash of particle soil under impact can be diminished when a fillet treatment is made for the bottom of hammer. With a given tamping energy, DC conducted from a lower distance with a heavier hammer will bring a better effect to the reinforcement of soils. The penetration of the hammer increases with the increase of tamping energy, and the proposed method can deal with DC problem even if the tamping energy is extremely high.

Geosynthetics are composite materials manufactured using different types of polymeric fibres, usually employed as anti-reflective cracking systems in asphalt pavements. Materials that compose geosynthetics can be damaged due to mechanical and thermal effects produced during the installation process under hot mix asphalts. In this paper, different polymeric fibres extracted from geosynthetics have been evaluated using nanoindentation tests. The main objective was to evaluate the effect of installation process (dynamic compaction and thermal damage) on the mechanical behaviour of individual polymeric fibres at nano-scale. To do this, elastic modulus (E) and hardness (H) of three different polymeric fibres commonly used in geosynthetics (polypropylene, polyester and polyvinyl-alcohol), in two testing directions and under two different states have been studied. Main conclusions of this work are that mechanical properties of geosynthetics individual fibres can change after installation, producing changes in the behaviour of geosynthetics at macro-scale with consequences in the pavement functionality, and that these changes are different depending on the material that composed the fibres.

In this paper, fabrication of Al7075-SiC nanocomposite using dynamic compaction is investigated. Evaluation of material tensile characteristics are often destructive and costly and impossible for small samples. Therefore, instrumented indentation tests can be employed to obtain the tensile stress-strain curve of the material. In this investigation, the tensile stress-strain curve of Al7075-SiC nanocomposite is obtained using combination of spherical indentation test, finite element (FE) simulation, and neural networks. To fabricate the Al7075/SiC nanocomposite samples, Al7075 micron-sized powder and SiC nano particles were mixed to obtain Al7075-5 vol% SiC, and Al7075-10 vol% SiC and the mixtures were mechanically milled. The mixtures were then consolidated under impact loading by a single-stage gas gun. The compaction was performed at 573 K temperature and a maximum relative density of 97.5% was obtained. The load-penetration curve for each nanocomposite sample was obtained using spherical indentation test on the compacted samples. The corresponding numerical curve for each sample was also obtained by finite element simulation of the indentation process. Finally, using the experimental and the FE results, the constants of Hollomon’s material model were determined using artificial neural networks (ANN). The results indicated that SiC nano-particles reinforcement of Al7075 increased the tensile strength of the nanocomposite by around 300%.

Geosynthetics are composite materials usually employed as anti-reflective cracking systems in asphalt pavements. However, materials that compose geosynthetics can be damaged due to mechanical and thermal effects produced during the installation process under Hot Mix Asphalts (HMAs). Although different studies have been carried out with the aim of evaluating the damage due to installation on geosynthetics, it is still not clear which variables have more influence on the deterioration of these materials and on the reduction of their properties. Therefore, the main objective of this paper was to evaluate the physical and mechanical damage produced on fibres of geosynthetics used as anti-reflective cracking systems in asphalt pavements. With this purpose, a new procedure to simulate in laboratory conditions the damage produced by the spread and compaction of a HMA on geosynthetics has been developed, by using dynamic compaction of aggregates at high temperatures. Thus, this procedure experimentally simulates the thermal and mechanical loads that geosynthetics undergo when they are used as anti-reflective cracking system. Thereby, different synthetic fibres such as polyester, polyvinyl-alcohol and glass fibres have been evaluated under the developed procedure. Finally, the reduction of physical and mechanical properties has been evaluated by using contrast tests, quantifying the damage produced on the fibres of geosynthetics after different deterioration procedures. Main conclusions of this research established that damage procedure using dynamic compaction of aggregates did not significantly reduce mechanical properties of the fibres strings evaluated by tensile tests on the studied geosynthetics. However, these results were different depending on the material that compose the geosynthetics.

In February 2015 Cofra Dynamic Compaction (CDC), a heavy Rapid Impact Compaction (RIC) technique to compact granular subsoil, was performed on the Berth 9 Quay Extension project in Felixstowe, UK. The extension consists of a 15.000m2 reclamation between sheet pile walls. The compaction of the reclamation was required to reduce future settlements and improve the properties of the sand behind the quay wall. An extensive compaction trial was performed before the start of the project to assess the compaction procedures and work method in relation to the specifications but also to assess the impact of the compaction on the Quay wall. Compaction effort was monitored during compaction with the use of the crane monitoring system which registers the (induced) settlement with increasing blows. The effect of the compaction has been measured with the use of pre- and post-compaction CPT's. The main quay wall displacements were continuously monitored by a manual station and a robotic total station. During the trial an inclinometer was used to gather more data. The paper focusses on the gathered data, findings and observations during the project and the compaction trials.

Dynamic compression experiments are conducted on micron-sized SiC powders of different initial densities with a split Hopkinson pressure bar. Digital image correlation is applied to images from high-speed X-ray phase contrast imaging to map dynamic strain fields. The X-ray imaging and strain field mapping demonstrate the degree of heterogeneity in deformation depends on the initial powder density; mesoscale strain field evolution is consistent with softening or hardening manifested by bulk-scale loading curves. Statistical analysis of the strain probability distributions exhibits exponential decay tail similar to those of contact forces, which are supposed to lead to the grain-scale heterogeneity of granular materials.

The present work is devoted to derive an analytical solution to the air blast response of dynamic compaction process of a sandwich composite containing a deformable front face and a cellular core. Shock wave model in association with the mass conservation and Newton׳s second law are employed to solve the problem. Both the weak fluid-structure interactions (FSI) such as those that are thought to occur due to air blast loading and the non-FSI cases are discussed and the results are compared with those available in the literature. The main contribution of this paper is that without having to numerically solve the governing equations, the form of the analytical solutions is capable of explaining the behaviour of enhancement zone for different choices of models including non-FSI, KNR (Kambouchev Noels Radovitzky) and FSI, which has potential advantages in practical applications. For instance, according to the results, the initial velocity of the face plate against the blast load will deter the cellular core compaction, which is basically the idea behind the “active armor”. Therefore, the model developed in this paper may provide useful information for the design of such armor structures.

This paper presented a dynamic fluid-solid coupled finite element (FE) method incorporating the soil cap yield hardening model to analyze the improvement on saturated foundation under dynamic compaction (DC). Biot’s dynamic u–U–p formulation was employed to describe the coupling of pore fluid and solid phases, which was discretized into finite elements by application of the Galerkin method and viscous Cartesian connectors. The proposed numerical model showed reasonably good agreement with the existing analytical solutions of one-dimensional transient loading problems and field measurement of dynamic compaction. The effects of groundwater table and soil permeability were examined via the development of excess pore water pressure, effective soil stress and void ratio. Results showed that groundwater table had a significant effect on the foundation improvement by DC. Higher groundwater table resulted in larger excess pore water pressure, and effective soil stress was not found to develop under the groundwater table during the compaction process. The decrement in the void ratio was only limited to soils located above the groundwater table, and a critical depth of groundwater table existed for the DC reinforcement in fine soil foundation, which was suggested to be 6 m for the DC reinforcement with the tamping energy of 2500 kN·m per blow. Four soil permeability coefficients of k = 10−2 m/s, 10−3 m/s, 10−5 m/s and 10−7 m/s were chosen in the parametric analysis, which represented gravel, coarse sand, silt and silty clay, respectively. Higher permeability resulted in lower excess pore water pressure and larger decrease in void ratio. However, the saturated foundation was not suitable to reinforce by dynamic compaction, no matter how much the soil permeability was. Compared to the increase in soil permeability, it was more crucial to lower the groundwater table before implementing dynamic compaction. Moreover, the gravel columns were preferred to be used to accelerate the drainage of groundwater than the sand columns.

The depletion of shallow-buried reserves has been driving the exploitation activities into the deeper crust, and the rising lithostatic stress thus poses substantial challenges to dynamic rock breakage. In this paper, we present new mechanistic insights into the effects of in-situ stresses on blast responses of intact rocks via integrated analytical and numerical analyses. An elastodynamic framework was first developed to characterize the blast wave propagation in pre-stressed rocks. The analytical solution suggests that the rock pressure can essentially promote dynamic compaction by diverting the explosive loading path and suppress fracturing by imposing circumferential compression. Such effects are more pronounced in the minor principal stress (σ3) direction of anisotropic stress fields. The rock responses under the coupled static-dynamic loadings were then simulated using a constitutive framework that was proven valid in this study for broad spectrums of pressures and strain rates. Image processing of the breakage patterns shows that the crushed zone contracts as the rock pressure rises. The crushed zone becomes elliptic in anisotropic stress fields, and its major axis coincides with the major principal stress (σ1) direction and declines more slowly than the minor axis aligned with σ3. The orientation distribution shows quantitatively that fractures get increasingly more clustered around σ1 as stress anisotropy rises, and the fracture density decreases more rapidly in equibiaxial conditions with greater vertical stresses. The consistent insights of the analytical and numerical studies can improve the mechanistic understanding of the evolution of dynamic rock behavior in different in-situ stress conditions.

Cost-effective exploration and exploitation activities hinge upon the production of optimum fracture networks via rock blasting. The concurrent increases in lithostatic pressure and temperature have posed significant challenges to mining at deeper formations within the Earth’s crust. To better understand the influences of in-situ stresses on rock blasting efficiency, a new closed-form elastodynamic solution to stress wave propagation from a spherical cavity in a general triaxial stress field is proposed. By transforming the solutions from the time domain to the space of stress invariants, novel insights into the intricate effects of in-situ stresses on dynamic rock behavior are obtained. This paper demonstrates that the different responses of radial and circumferential stresses to static and dynamic loadings draw the initial stress states closer to the yield envelope and thus divert the loading paths during ensuing dynamic impacts. The resulting changes in the patterns of stress trajectories hence cause various mechanisms of dynamic rock yielding in triaxial stress fields under different loading amplitudes. Based on spherical charges rather than the more typical cylindrical ones, our results show quantitatively that in-situ stresses can impair blast fragmentation by promoting dynamic compaction and delaying or even inhibiting tensile fracturing. While dynamic yielding becomes complex in anisotropic stress fields, the major principal stress (σ1) direction tends to be associated with better fragmentation efficiency for the same mode of yielding and radial cracks also propagate preferentially along σ1. Moreover, rational design of loading intensity can enhance rock fragmentation efficiency by promoting brittle yielding in certain in-situ stress conditions.

Ground treatments and post-construction settlement (PCS) control technologies are hot topics within the loess high-filling embankment (LHFE) research area. Taking the test section of a high filling airport constructed on a thick loess foundation as an example, the creep behaviour of undisturbed loess and compacted loess under high-pressure and different initial conditions are investigated using laboratory tests. The Mod-Burgers creep model of loess is proposed; a FLAC-3D simulation study is conducted to explore the PCS of high fill embankment under different influence factors. The research results show that the proposed Mod-Burgers model and equivalent creep modulus clearly reflect the long-term deformation characteristics of compacted and undisturbed loess. The filling height has the greatest impact on the PCS of high filling body, the compaction degree and water content are the second most important influence factors on the PCS of the high filling body. The pile length and pile spacing are the third important influence factors on the PCS of the original foundation. For the construction control of an LHFE in the gully, different treatment methods should be adopted according to different functional zones. It is recommended to adopt the dynamic compaction method for shallow loess foundation, and the collapsibility of loess should be eliminated. For thick loess foundation, the vibrating sinking gravel pile method is well-suited for treating an original foundation with low water content; cement-fly ash-gravel pile and lime-soil compaction pile are suitable for treating an original foundation with high water content.

A large-scale field test to investigate vibration velocities from dynamic compaction of soil-aggregate mixture in a fill at a Chengde airport construction site, China, was carried out. The propagation and evolution of the vibration waveforms, wave amplitudes, and wave frequencies were analyzed and the mechanism by which the strength of the soil-aggregate fill was reinforced by the tamping energy was studied. The results show that there are only two vibration forms, shock waves and vibration waves, in the soil-aggregate mixture under dynamic compaction. The dominant vibration frequency and optimum frequency band for dynamic compaction are determined and the concept of critical elastic vibration velocity for soil-aggregate mixtures is proposed. A method for determining the magnitude of this vibration is demonstrated. During and after compaction, the fill could be divided into three zones, an impact reinforced zone, plastic stress wave reinforced zone, and elastic area in which the soil is not reinforced. These zones are defined by the spatial distribution of the vibration velocities and the correspondingly increased soil densities. Finally, the dynamic compaction reinforcement mechanism for a coarse-grained soil-aggregate mixture is explained and the reinforcement process is divided into two stages. In addition, a suggestion for the best layer thickness for dynamic compaction of fill is proposed.

In this study, WC particles of 1–3 μm were blended with two different sizes of Co particles and sintered conventionally at two different temperatures. Compaction of initial powders was carried out using a relatively new dynamic compaction method called Magnetic Pulsed compaction (MPC). The maximum Vickers hardness for the samples found was around 1353 HV (13.27 GPa), while the maximum fracture toughness was observed at 4.6 MPa · m 1/2 . The marked changes in density, hardness, fracture toughness and crack behavior observed in the samples indicate strong correlations among particle size, sintering process and mechanical properties of cemented carbides. In addition, the nature of crack initiation and propagation, which is indicative of the trend in fracture toughness of materials, was observed and analyzed.

Theoretical analysis of the propagation of stress waves in layered cellular solids with different densities, and consequently strengths, is carried out to deepen the understanding of their dynamic compaction due to impact loading. The cellular topology is neglected and homogeneous properties are assumed. Two types of plastic waves are distinguished depending on the layers density arrangement. Only waves of strong discontinuity occur when the layers’ densities increase in the direction of propagation of the primary wave. Multiple reflections of the stress waves from the layer interfaces are identified and studied for this type of the layers density arrangement. Simultaneous propagation of a wave of strong discontinuity in the proximal layer and a simple wave in the subsequent layers occur when the layers’ densities decrease in the direction of propagation of the primary wave. Two types of loading conditions: an impact of a stationary cellular block by a rigid mass and an impact of a cellular block on a rigid wall are analysed. It is assumed that the constituent materials in the layered solids exhibit strain hardening. The plastic strain is sought as a function of the impact velocity and material properties when using the characteristic Hugoniot strain–velocity relationship. FE models using ABAQUS are constructed and numerical simulations are carried out to verify the predictions of the theoretical analysis. The potential of layered cellular materials to design more efficient structural components when subjected to intensive dynamic loading is briefly discussed when comparing the response of some layered configurations with their uniform density counterparts of equal mass.

Theoretical analysis of the propagation of stress waves in cellular solids with non-uniform density, and consequently strength, is carried out to deepen the understanding of their dynamic compaction due to impact loading. Materials with continuously varying density in the direction of loading are considered when analysing the response to two types of loading conditions: an impact of a stationary cellular block by a rigid mass and an impact of a cellular block on a rigid wall. It is assumed that the local stress–strain characteristics of the graded materials exhibit strain hardening. The plastic strain field in the deformed graded cellular solid is sought here as a function of the impact velocity and material properties when using the Hugoniot material representation. It is shown that the initial density variation with respect to the boundaries of a finite thickness block has a significant effect on the history of the stresses and strains during the compaction process. FE models using ABAQUS are constructed and numerical simulations are carried out to verify the predictions of the theoretical analysis. Attention is paid to the energy absorption capacity of the materials depending on their initial density distribution when comparing their dynamic responses with the response of equivalent mass cellular block with uniform density. Significant advantages in using density graded cellular solids in finite thickness layers are not identified for the analysed loading rate.

© 2015 Elsevier Ltd. The effect of MWCNT introduction in a polycarbosilane based ceramic on its electrical properties is presented. The electrical conductivity of two MWCNT powders was measured under dynamic compaction up to 20MPa when it reached 3 5S/cm. The compaction behavior was also analyzed and modeled. A composite was then realized using allylhydridopolycarbosilane SMP10® and divinylbenzene as matrix. Intact 10mm MWCNT SiC ceramic discs samples with 2wt. filler load were produced pressure less via liquid route despite the linear shrinkage of about 30. Nanotubes microstructure and distribution in the matrix were confirmed after pyrolysis with TEM and SEM analysis. Anyhow similar electrical conductivity values after pyrolysis between the loaded and unloaded samples were measured. The microstructure analysis via XRD and TEM revealed that the percolative carbon network formed through the use of divinylbenzene improves the electric conductivity more than that of MWCNT addition and also simplifies the whole process.

The dynamic compaction (DC) method is an effective ground treatment technique that is widely used for a variety of soil types and conditions, particularly in loess areas. However, DC is rarely applied to ground where thick collapsible loess is present. The conventional DC method exerts an energy level of no more than 5000 kN·m. Although the DC for collapsible loess treatment is increasing, the use of higher energy inputs for similar soil conditions is quite limited. In this paper, dynamic compaction with a maximum energy level of 12,000 kN·m was applied to a collapsible loess site in the city of Qingyang in the Gansu Province in northwestern China. Field tests were conducted to determine the optimum DC operational parameters. The field studies included deformation tests, standard penetration tests (SPT), static penetration tests and plate load tests. The deformation tests included the crater depth per drop and the whole test zone elevations before and after DC. The standard and static penetration tests and plate load tests were performed to evaluate the final effect of DC. The collapsibility was also measured before and after DC. The allowable ground-bearing capacity and the depth of improvement at the site after treatment achieved no less than 250 kPa and 10 m, respectively, and the collapsibility was greatly reduced or was completely eliminated.

The dynamic behavior of granular materials has importance to a variety of engineering applications. Structural seismic coupling, planetary science, and earth penetration mechanics, are just a few of the application areas. Although the mechanical behavior of granular materials of various types have been studied extensively for several decades, the dynamic behavior of such materials remains poorly understood. High-quality experimental data are needed to improve our general understanding of granular material compaction physics. This paper will describe how an instrumented plunger impact system can be used to measure pressure-density relationships for model materials at high and controlled strain rates and subsequently used for computational modeling.

Quasi-static and hot dynamic compactions of Al7075/SiC nanocomposite powder are studied in this work. Mechanically milled micron-sized Al7075 with different amounts of SiC nano particles (SiC np ), 0 vol%, 5 vol%, and 10 vol%, are used to fabricate the samples. Dynamic and quasi-static hot compaction is conducted at strain rates of 10 3 s −1 and 8 × 10 −3 s −1 , respectively. The hot compaction conducted at the process temperature of 698 K produces nanocomposite samples with relative densities up to 98%. The micro-structural and mechanical behaviors of samples such as micro hardness and stress–strain curves under quasi-static and dynamic loadings are also investigated. The results show improvement in micro hardness of the material. The quasi-static and dynamic tests are carried out using Instron testing machine and split Hopkinson pressure bar (SHPB), respectively. The improvement is believed to be due to strengthening mechanisms such as Orowan and enhanced dislocation density induced by thermal mismatch phenomenon and not by grain refinement described by the Hall–Petch effect. The results from quasi-static compressive tests reveal higher strength for quasi-static hot pressed samples than those produced under dynamic compaction. However, the dynamic compressive tests using SHPB indicate similar compressive strength for both quasi-statically and dynamically compacted samples.

A theoretical model for the compaction curve of fine-grained soils at various compaction efforts for the entire range of water content is presented in this study. The prediction method is based on the assumption that the compaction curve represents the state surface at the yield state in an unsaturated condition. Thus, for each applied compaction effort, the compaction curve relates to one yielding point on the saturated normal consolidation line (NCL). For a given soil, the model requires the NCL, Src, and one point from any compaction curve to predict the compaction curves for different compaction efforts. Moreover, the lines of equal suctions on the compaction curves can be determined if the SWCC, the wetting path, is known. The model introduced here provides additional theoretical understanding of the soil׳s volume change behavior of the compaction curve. The model was verified in two ways: first it was verified quantitatively, by experimental results, and second it was verified qualitatively, by examining the relationships from other models in the literature. The model was further applied to experimental data reported in the literature on previous static and dynamic compaction tests. The results show that the model fits the experimental data very well. Finally, a simple chart, based on this model and using only liquid limits, is presented to estimate γdmax and OMC quickly.

This manuscript investigates the effect of compact pressure during in situ synthesis of Al2O3-TiB2 composite by self-propagating high-temperature synthesis (SHS) process on microstructure, toughness, hardness and modulus. The oxidation behaviour of the composite was also studied. The porosity was found to decrease with the increase in dynamic compaction pressure and grains became finer forming a nano-composite with very fine boride grains in alumina matrix. The densification was mostly complete at 13 MPa about 95%-96% densification, and it remained similar at higher loads up to 18 MPa. Microhardness increased with compaction pressure, and a maximum average hardness of 3536 H-v was obtained for sample compacted at 18 MPa pressure. Hardness and modulus under dynamic indentation did not show clear trend of increase with compaction pressure as in microhardness. The average hardness of 22.684 GPa and a mean modulus of 360.904 GPa was measured for 13 MPa compacted sample. Fracture toughness was found to increase with compaction pressure. Oxidation studies showed stability against oxidation up to 900 degrees C, and no significant changes in properties were observed. It was observed that during the SHS dynamic synthesis of Al2O3-TiB2 composite, the compacting pressure had lot effect on microstructure, hardness, modulus and densification. A high hardness with reasonable toughness and oxidation resistant up to 900 degrees C temperature has been achieved in Al2O3-TiB2 composite. 2013 Elsevier Ltd. All rights reserved

Effect on microstructure, hardness, modulus, fracture toughness and oxidation behaviour of Al 2 O 3 –ZrB 2 composite with different percentages of Titanium as diluents during the SHS reaction has been studied. It was observed that Ti addition leads to formation of different phases such as TiB 2 , ZrO 2, TiB besides ZrB 2 and Al 2 O 3 . The hardness and modulus were found to be around 21 GPa and 350 GPa, respectively for 10 wt.% Ti addition in dynamic depth indentation. Oxidation study of the sample having 25 wt.% Titanium showed no significant change in phase and mechanical properties after 700 °C oxidation. The toughness of 20 wt.% Ti sample showed highest fracture toughness.

This paper presents a method for incorporating dual-phase u–U wave propagation analysis for saturated porous media in commercial codes. Biot’s formulation is first re-formulated in terms of effective stress and pore pressure, followed by its finite element discretization. The method of incorporating the dual-phase computation involves representing the solid and pore fluid phases by two overlapping meshes with collocated elements and nodal points. Viscous coupling between the solid and fluid phases are realized by connecting each pair of collocated nodal points using viscous Cartesian connectors. Volumetric compatibility between the solid and fluid phases is enforced by coding the behaviour of the two phases and their volumetric interaction within a user-defined material subroutine. Non-linear behaviour of the soil skeleton can also be prescribed within the same subroutine. Comparison with existing analytical or numerical solutions for three one-dimensional elastic problems shows remarkably good agreement. Finally, a three-dimensional elasto-plastic example involving impulsive surface loading on dry sand overlying saturated sand, which is akin to a dynamic compaction problem, is analyzed to demonstrate the potential application of the u–U analysis on a more realistic transient loading problem. The results of the analysis highlight the importance of the slow wave in dynamic compaction process. Although this approach was developed on the ABAQUS Explicit platform, it is, in principle, applicable to other existing codes with the right features. Its main advantage is that users can still access the computational functionalities and stability, as well as pre- and post-processing features that often come with commercial codes.

The Dynamic Replacement (DR) technique has been used successfully to improve soft soils. It uses the dynamic compaction energy to drive granular materials down into the soils, forming a pillar of 2–2.5 m diameter. In this paper, a 30,000 m2 study is used to evaluate the performance of the technique. Cone penetration tests (CPTs) were carried out before ground improvement to analyze the soil and select the appropriate technique. Post improvement CPTs (inside and between pillars) and load tests were carried out to confirm that the design requirements (bearing capacity and settlement) are met. It is proposed to use the Schmertmann [1] and Schmertmann et al. [2] method for calculating the settlements. However, to make it applicable to the case of DR for clayey soils, a methodology is proposed to calculate an equivalent tip resistance based on the DR replacement ratio. The values of the equivalent tip resistance are used to calculate the equivalent modulus of elasticity of the soil for settlement calculations. A finite element model has been built to simulate the revised formula, and the calculated settlements have shown a good agreement with the conducted measurements and the finite element model results as well. Keywords: Dynamics, Site investigation, Geotechnical engineering

The deformation of a stationary foam block due to an impact by a foam projectile is analysed. Several combinations between the properties and geometry of the projectile and stationary block are used in order to reveal the characteristic features of deformation under the condition of decreasing velocity during the impact event. No details of the cellular geometry are analysed and it is assumed that the foam is a homogeneous material. The dynamic compaction of the foam block and projectile is described by a one-dimensional model. The model is based on the propagation of a strong discontinuity unloading wave when using the actual experimentally derived stress–strain curves for three aluminium based foam: Alporas with 9% relative density and Cymat foams with 9.3% and 21% relative density. Numerical simulations were carried out to verify the proposed model. It is shown that the strain distribution in the foam blocks significantly depends on the material properties and boundary conditions. It is shown that a more distinct boundary between the compacted and undeformed foam can be observed in the projectile while the strains in the stationary block usually decrease gradually with the increase of the distance travelled by the compaction wave from the interaction boundary. It is demonstrated that the proposed approach is capable of predicting the history and final strain distribution in the foam with sufficient accuracy.

We performed impact experiments into mixtures of chondrule analogs and different dust materials to determine the dynamic-pressure range under which these can be compacted to achieve porosities found in chondritic meteorites. The second objective of our study was to test whether or not fine-grained dust rims around chondrules can be formed due to the dynamic compaction process. In our experiments, aluminum cylinders were used as projectiles to compact the chondrite-analog samples in a velocity range between 165 m s −1 and 1200 m s −1 . The resulting impact pressures in the samples fall between ∼90 and ∼2400 MPa. To measure the achieved porosities of our samples, 25 samples were analyzed using computer-aided tomography. We found volume filling factors (porosities) between ϕ = 0.70 (30%) and ϕ = 0.99 (1%) which covers the observed range of volume filling factors of carbonaceous chondrites (CC) and ordinary chondrites (OC). From our experiments, we expect CM chondrites to be likely compacted in a pressure range between 60 and 150 MPa, CV chondrites appear to be compacted with pressures between 100 and 500 MPa, and for OCs we only determined a lower limit of the compaction pressure of 150 MPa. These dynamic compaction pressures are in good agreement with the typical shock stages of the chondrites, and thus can confirm that CM chondrites are less shocked than CV chondrites and significantly less shocked than OCs. Finally, we found a factor of 10 difference in the dynamic-pressure compaction range of CCs and OCs that allows us to infer either a larger distance between the formation location of the two chondrite families than current models predict or a strong difference in orbital eccentricities for the two groups. As for the high-density rims found around chondrules, we can show that these do not form in dynamic compaction processes as studied in this paper.

As granular soils may be compressible or have inadequate strength, compaction is particularly useful when soils are subjected to dynamic loading or cyclic loading. A new laboratory apparatus for investigating dynamic compaction has been designed and fabricated. The basic principle of this new technique is to introduce vibrations during the expansion process in static compaction grouting. In these tests, the injection pressure, the excess pore water pressure, and the change in void ratio of the specimens are measured. The main focus is to investigate the development of the injection pressure, the void ratio, and the excess pore water pressure due to dynamic compaction and the subsequent consolidation of the soils. In addition, the relative density of the soils is used to evaluate the dynamic compaction efficiency. Scaled laboratory experiments are conducted to study the effect of this dynamic compaction frequency on compaction efficiency. The experimental results show that the change in void ratio in the dynamic compaction tests is about four times greater than that in the static compaction tests. Dynamic compaction frequency plays an important role in soil densification due to dynamic compaction.

The dynamic compaction (DC) method is an effective ground treatment technique widely used in a great variety of soil types and conditions, particularly sandy materials and granular fills. However, the application of DC on very fine desert sandy ground is rare. In this study, dynamic compaction with a high energy level of 8000 kN·m was applied to a desert sand site in Inner Mongolia, China. During DC construction, field tests were conducted to determine the optimum DC operation parameters. This field study included deformation tests, dynamic penetration tests and plate-load tests. Deformation tests included the crater depth per drop and the whole test zone elevations before and after DC. Dynamic penetration tests and plate-load tests were performed to evaluate the final effect of DC. It was found that the allowable ground-bearing capacity and the depth of improvement at the site achieved no less than 450 kPa and 12 m, respectively, as a result of high energy dynamic compaction.

A comprehensive approach is presented in this study for the prediction of the ground vibration due to the collapse of a 235 m high cooling tower, which can be caused by various accidental loads, e.g., explosion or strong wind. The predicted ground motion is to be used in the safety evaluation of nuclear-related facilities adjacent to the cooling tower, as well as the plant planning of a nuclear power station to be constructed in China. Firstly, falling weight tests were conducted at a construction site using the dynamic compaction method. The ground vibrations were measured in the form of acceleration time history. A finite element method based “falling weight-soil” model was then developed and verified by field test results. Meanwhile, the simulated collapse processes of the cooling tower under two accidental loads were completed in a parallel study, the results of which are briefly introduced in this paper. Furthermore, based on the “falling weight-soil” model, “cooling tower-soil” models were developed for the prediction of the ground vibrations induced by two collapse modes of the cooling tower. Finally, for a deep understanding of the vibration characteristics, a parametric study was also conducted with consideration of different collapse profiles, soil geologies as well as the arrangements of an isolation trench. It was found that severe ground vibration occurred in the vicinity of the cooling tower when the collapse happened. However, the vibration attenuated rapidly with the increase in distance from the cooling tower. Moreover, the “collapse in integrity” mode and the rock foundation contributed to exciting intense ground vibration. By appropriately arranging an isolation trench, the ground vibration can be significantly reduced.