Penetration Test Research Articles

A centrifuge modelling setup for dewatering, rewetting, and characterizing soil deposits

Dewatering in soils serves various purposes in the field of geotechnical engineering as well as other disciplines. In geotechnical engineering, dewatering is effective for improving stability, reducing settlements, and limiting seepage of contaminated pore fluid. This study details the development of an experimental setup that enables dewatering and rewetting soil deposits in-flight in a geotechnical centrifuge while the pore pressures/suctions and moisture contents are measured. Cone penetration tests and shear wave velocity measurements are also used to characterize the material in-flight. Detailed discussion is provided regarding the construction of the tensiometers and calibration of the moisture content probes. Tests are performed on two coal combustion products (CCPs) to exemplify the capabilities of the equipment. Illustrative test results provide time histories and profiles of soil suction and water content at different depths, agreeing well with measurements from laboratory soil-water retention curves. The results also show that dewatering of the CCP deposits leads to significant increases in strength and stiffness, and that after subsequent rewetting, the material maintains a permanent increase in stiffness. The developed system enables an economical and reliable study of the impacts related to dewatering and rewetting cycles to fulfill research purposes in a broad range of engineering disciplines.

Development of a Cone Penetration Testing Apparatus with a Textured Shaft

The anisotropy of shear resistance depending on friction direction can be selectively utilized in geotechnical structures. For instance, deep foundations and soil nailing, which are subject to axial loads, benefit from increased load transfer due to greater shear resistance. In contrast, minimal shear resistance is desirable in applications such as pile driving and soil sampling. Previous studies explored the shear resistance by interface between soil and surface asperities of a plate inspired by the geometry of snake scales. In this study, the interface friction anisotropy based on the load direction of cones with surface asperities is evaluated. First, a laboratory model chamber and a small-scale cone system are developed to quantitatively assess shear resistance under two load directions (penetration ⟶ pull-out). A preliminary test is conducted to analyze the boundary effects for the size of the model chamber and the distance between cones by confirming similar penetration resistance values at four cone penetration points. The interface shear behavior between the cone surface and the surrounding sand is quantitatively analyzed using cones with various asperity geometries under constant vertical stress. The results show that penetration resistance and pull-out resistance are increased with a higher height, shorter length of asperity and shearing direction with a decreasing height of surface asperity.

Evaluation of state parameter interpretation methods using CPT calibration chamber data

The cone penetration test (CPT) is widely used to determine the in situ state parameter of soils because it provides continuous data and excellent repeatability at a relatively low cost. Accurate interpretation of the state parameter from CPT is the basis for evaluating the strength of granular soils, including assessing liquefaction susceptibility in important structures such as tailings storage facilities. A few interpretation methods are used in practice. They use two different overburden stress normalisation schemes on tip resistance. These methods vary in how much information they utilise to differentiate among soils. This paper evaluates these methods by applying them to an extensive database of calibration chamber tests. Then, the state parameter interpreted by each method is compared with that determined from laboratory data. The database includes manufactured sands, natural sands, and clean sand tailings. The soils were selected such that both calibration chamber testing and triaxial compression data were available from the literature. This evaluation serves as a minimum requirement for applying these methods in engineering projects, especially those dealing with challenging soils such as fines-rich tailings. This study suggests that methods that account for soil properties and in situ horizontal stresses perform better than those that do not.

Study on Welding Characteristics and Parameters of Gas Metal Arc Welding for A516 Grade 70 Steel with ER70S-6 and ER308LSi Filler Materials

Welding is a crucial process in joining metals, especially in the fabrication industry. Thisresearch aimed to investigate the effects of using two different filler materials, ER70S-6 and ER308LSi, with nine combinations of wire feeder speed (WFS) and shielding gas flow rate (GFR), on weld joints. The study focused on the weld quality and material properties of Gas Metal Arc Welded (GMAW) butt joints of ASTM A516 G70 plates, characterized through visual inspection, liquid penetrant testing, tensile testing, hardness testing, and optical microscopy. Results indicated that the highest ultimate tensile strength and hardness were achieved at 4 m/min WFS and 15 L/min GFR with ER70S-6, and 5 m/min WFS and 20 L/min GFR with ER308LSi. The specimens welded with ER308LSi demonstrated superior mechanical properties compared to those welded with ER70S-6. Additionally, the study revealed the influence of microstructural changes from the base metal (BM) to the heat-affected zone (HAZ) and fusion zone (FZ), with finer and more compact grain structures contributing to higher hardness values. These findings underscore the importance of selecting appropriate filler materials, WFS, and GFR to achieve the desired weld quality and material properties for A516 G70 low-carbon steel welded joints.

An Automated Penetration Testing Framework Based on Hierarchical Reinforcement Learning

Given the large action space and state space involved in penetration testing, reinforcement learning is widely applied to enhance testing efficiency. This paper proposes an automatic penetration testing scheme based on hierarchical reinforcement learning to reduce both action space and state space. The scheme includes a network intelligence responsible for specifying the penetration host and a host intelligence designated to perform penetration testing on the selected host. Specifically, within the network intelligence, an action-masking mechanism is adopted to shield unenabled actions, thereby reducing the explorable action space and improving the penetration testing efficiency. Additionally, the host intelligence employs an invalid discrimination mechanism, terminating testing after actions that do not alter system states, thereby preventing sudden increases in the number of neural network training steps for an action. An optimistic estimation mechanism is also introduced to select penetration strategies suited to various hosts, preventing training crashes due to value confusion between different hosts. Ablation experiments demonstrate that the host intelligence can learn different penetration strategies for varying penetration depths without significant fluctuations in training steps, and the network intelligence can coordinate with the host intelligence to perform network penetration steadily. This hierarchical reinforcement learning framework can detect network vulnerabilities more quickly and accurately, significantly reducing the cost of security policy updates.

Penetration test and numerical simulation of scaled earth penetrator for coral aggregate seawater concrete cylindrical target

In order to study the mechanical properties of coral aggregate seawater concrete (CASC) subjected to the penetration of scaled earth penetrator, firstly, the penetration depth and damage of CASC and ordinary sand-gravel concrete under the same conditions were compared by experimental research, and the influence of concrete strength and projectile velocity on penetration performance was analyzed. Then, the three-dimensional mesoscopic model is used to simulate the test conditions, and the failure process and failure mechanism are analyzed. The results show that under the same penetration conditions, as the strength of CASC increases, the crater diameter becomes larger, which is consistent with the conclusion of ordinary concrete (OPC). During the penetration process, the CASC and the mortar are destroyed as a whole. At the same time, as the penetration speed of the projectile increases, the width of the crack on the surface of the target increases. When the projectile velocity is low, the anti-penetration performance of CASC with the same strength is not as good as that of OPC with the same strength. For the target with a thickness of 25 cm, the penetration depth of the concrete target with the same strength will increase with the increase of the velocity of the projectile. When the velocity of the projectile is constant, the penetration depth of CASC will decrease with the increase of the strength. The numerical simulation results obtained by using the K & C mesoscopic model are in good agreement with the experimental results, indicating that the model and its model parameters have high reliability in the analysis of CASC penetration mechanical properties.

The Hardness Change Due to High-Speed Impact on A36 Steel on Penetration Testing of School Barrier Systems

Impact Doors and Windows are increasingly on demand for safety and security. They already existed, standardized in in continual improvement.

Estimation of Undrained Shear Strength of Soil from CPTu Data

The estimation of undrained shear strength ( ) from Cone Penetration Test with pore pressure measurement (CPTu) for two sites was investigated in this research. The CPTu cone parameters: net cone resistance ( ), excess pore pressure ( ) and effective cone resistance ( ) were used to estimate the for the two sites and the values obtained were compared with the undrained shear strength in triaxial compression ( calculated from Anisotropically Consolidated Undrained Compression (CAUC) triaxial test results. For the clayey silt site, the undrained shear strength from the CAUC tests are higher compared to the values obtained from the CPTu, and the highest correlation was obtained from the effective cone resistance parameter . For the quick clay test site, the value and were relatively the same and showed stronger correlation as compared to the clayey silt site. The measured from the cone parameter had the highest correlation. It was concluded that and yields good correlation with the CAUC results for the clayey silt and quick clay test sites respectively as compared to the other con parameters.

Advanced Penetration Testing and Vulnerability Assessment

Advanced Penetration Testing and Vulnerability Assessment

Understanding Penetration Testing for Evaluating Vulnerabilities and Enhancing Cyber Security

In response to the increasing incidence of cyber-attacks, organizations are prioritizing security testing for their software applications and products. Among the most effective methods for identifying vulnerabilities is penetration testing, which involves simulated attacks on systems to uncover weaknesses that could be exploited by malicious actors. This method not only aids in identifying and remediating security flaws but also evaluates a system's ability to withstand unexpected threats. This paper provides an in-depth exploration of penetration testing, detailing its stages, methodologies, and the role of web application firewalls. A penetration test systematically assesses the security of IT infrastructures by exploiting vulnerabilities in systems, applications, and user behaviours. The findings from these tests are essential for IT management, guiding strategic decisions and prioritizing remediation efforts. Ultimately, the primary aim of penetration testing is to evaluate the risk of a system breach and its potential impact on organizational resources and operations.

Evaluation of the Effects of Cultivar and Location on the Interaction of Lentil Seed Characteristics with Optimal Cooking Time

The most important product of the lentil crop (Lens culinaris Medik) is the seeds. The main seed characteristics are their size, color, and the cooking time required to make them edible. Cultivar, location of cultivation, and their interaction are the primary factors of raw or cooked seed characteristics. The study examined the impact of five different lentil cultivars (Dimitra, Elpida, Thessalia, Samos, and 03-24L), as influenced by the cultivation environment in four different zones or nine different locations in Central-Northern Greece, on cooking time. The optimal cooking time (OCT) was calculated by cooking the seeds for 0–60 min to determine the percentage of cooked seeds using the penetration test. OCT was associated with the characteristics of both raw (mass of 1000 seeds, external color, and the percentage of mature/immature seeds) and cooked (color and organoleptic characteristics of the cooking media as well as mass increase and hardness and organoleptic characteristics of the seeds) seeds for 30 min. Depending on location, each cultivar had a different mass of 1000 seeds; Elpida had the highest mass (63.9 g), and Dimitra had the lowest (33.1 g). This was linked to OCT, which was among the highest (57.5 min) for Elpida, lowest (49 min) for Dimitra, and intermediate for Thessalia, Samos, or 03-24L. The average OCT was 55.9 min for all samples. The seed from the five locations with the shortest OCT was considered appropriate for human consumption. Two locations yielded seeds with intermediate OCT, while the other two produced the highest OCT; these were recommended for processing or propagation. In this study, the cultivar factor had a greater effect on raw seed characteristics, while the location factor had a greater effect on cooked seed characteristics and OCT than either the location, the cultivar factor, or the cultivar x location interaction.

Suitability techniques for transforming marginal lands to support building infrastructures in parts of Rivers State, Nigeria

This study examined sustainability techniques for transforming marginal lands to support building infrastructures in parts of Rivers State, Nigeria. The study adopted the cross-sectional survey research design method employing the use of standard penetration approach utilizing Geographic Information System analysis. Marginal lands were delineated as margins of watrbodies using the polygon method in ArcGIS, and were created as a feature class for polygon data (shape file). The locations, river margins and roads formed point data, polygon data and line data respectively. Digitisation was achieved using Orthophoto Image in ArcGIS 10.0 software where seven geotechnical boreholes were located and drilled using permission rig to a depth of 10.5m in five local government areas of Rivers State. In-situ standard penetration testing and soil sampling for laboratory geotechnical properties was done using standard laboratory techniques. Findings of the analysis show that silty and sandy clay are the dominant soil within the foundation depth of 1-2.5m which are underlained by clays and sands of varying densities and grain sizes with their specific gravity value of ranges of 1.9 – 2.66 depicting that the areas are underlined by organic, diatomaceous and high porosity permeability soils deposits under water logged conditions. The cohesive strength of the soils vary from 65KN/m 2 - 115KN/m 2, angle of internal friction ranged from 0o – 10o and shear strength ranged from 110KN/m 2 – 147.46KN/m 2 and the allowable bearing capacities of 180.22KN/m 2 – 236.05KN/m 2. The stability techniques for the transformation of the land to support building infrastructures are pre-construction soil stabilization and marginal land reinforcement. The study thus recommends for building summation of consolidated techniques for sustainability of infrastructures.

Empowering urban development: geospatial modeling and zonation mapping in New Kabul City, Afghanistan

The main difficulties in urban development, choosing a location, and creating preventative safety precautions are accurately characterizing and valuing subsurface soil information from a geotechnical and geological standpoint. This paper discusses how to define and build geotechnical subsoil soil zonation maps (SZMs) for the new Kabul city, Afghanistan, using traditional ArcGIS software assessing Kriging interpolation approaches. With the city’s expansion plans, including New Kabul City’s development, our research supports informed urban development strategies. Subsoil data from 2,13 locations across the city were collected from geotechnical studies, focusing on soil classification, Standard Penetration Test (SPT-N values), undrained shear strength, and consolidation characteristics up to 15 m depth. SPT-N and soil type were used to create SZMs, and other parameters were used to evaluate bearing capacity and settlement. The results revealed that SPT-N values divided the research region into three main sections: A (8–>50), B (13–>50), and C (14–>50). The subsurface strata consist of low-plasticity clay (CL) and clayey sand (SC) underlain by highly plastic clay (CH) and silt (MH). Linear regression predicted SPT-N values with depth, showing a strong R2 of 0.95. This speeds up sub-soil stiffness and strength assessments during building project planning and feasibility studies. The shallow Kabul foundation has an allowable bearing capacity of over 100 kPa, making it suitable for lightly loaded buildings. Predicting SPT-N levels has an 85% correlation coefficient, while soil type has 94%. Accurate geotechnical data on the soil’s underlying layers will help characterize the site and identify future project risks.

Experimental investigation of circumnutation-inspired penetration in sand

Abstract Probes that penetrate soil are used in fields such as geotechnical engineering, agriculture, and ecology to classify soils and characterize their properties in situ. Conventional tools like the Cone Penetration Test (CPT) often face challenges due to the lack of reaction force needed to penetrate stiff or dense soil layers, necessitating larger drill rigs. This paper investigates more efficient means of penetrating soil taking inspiration from a plant-root motion known as circumnutation. Experimental penetration tests on sands are performed with circumnutation-inspired (CI) probes that advance at a constant vertical velocity (v) while simultaneously rotating at a constant angular velocity (ω). These probes have tips have a given bent angle (α) and bent length (L1). The variation of the mobilized vertical force (Fz), torque (Tz), and the mechanical work components with the relative tangential to vertical velocity (\omega R/v) is investigated along with the effects of probe geometry, v, and soil relative density (DR). The results show that the soil penetration resistance does not vary with v, but it increases as \alpha, L1, and DR are increased. Fz decays exponentially with increasing ωR/v, Tz initially increases and then plateaus, while total work (WT) shows little magnitude changes initially but later increases monotonically. The mechanisms governing these trends are identified as changes in the probe projected areas and mobilized normal stresses due to differences in probe geometry and the effects of ωR/v on the resultant force direction and soil disturbance. The results show that CI penetration within a specific range of ωR/v leads to small increases in WT (i.e., ≦25%), yet mobilizes Fz magnitudes that are 50 to 80% lower than that mobilized during non-rotational penetration. This indicates that CI penetration can be adopted for in situ characterization or sensor placement with smaller vertical forces, allowing for use of lighter rigs.

A Novel Landfill Liner Material for Solidified Lake Sediment Based on Industrial By-Product and Construction Waste: Engineering Behavior and Cr(VI) Breakdown Characteristics

Engineering sludge, industrial waste, and construction waste are marked by high production volumes, substantial accumulation, and significant pollution. The resource utilization of these solid wastes is low, and the co-disposal of multiple solid wastes remains unfeasible. This study aimed to develop an effective impermeable liner material for landfills, utilizing industrial slag (e.g., granulated blast furnace slag, desulfurized gypsum, fly ash) and construction waste to consolidate lake sediment. To assess the engineering performance of the liner material based on solidified lake sediment presented in landfill leachate, macro-engineering characteristic parameters (unconfined compressive strength, hydraulic conductivity) were measured using unconfined compression and flexible wall penetration tests. Simultaneously, the mineral composition, functional groups, and microscopic morphology of the solidified lake sediment were analyzed using microscopic techniques (X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy + energy dispersive spectroscopy). The corrosion mechanism of landfill leachate on the solidified sediment liner material was investigated. Additionally, the breakdown behavior of heavy metal Cr(VI) within the solidified sediment liner barrier was investigated via soil column model experiments. The dispersion coefficient was computed based on the migration data of Cr(VI). Simultaneously, the detection of Cr(VI) concentration in pore water indicated that the solidified sediment liner could effectively impede the breakdown process of Cr(VI). The dispersion coefficient of Cr(VI) in solidified sediments is 5.5 × 10−6 cm2/s–9.5 × 10−6 cm2/s, which is comparable to the dispersion coefficient of heavy metal ions in compacted clay. The unconfined compressive strength and hydraulic conductivity of the solidified sediment ranged from 4.90 to 5.93 MPa and 9.41 × 10−8 to 4.13 × 10−7 cm/s, respectively. This study proposes a novel approach for the co-disposal and resource utilization of various solid wastes, potentially providing an alternative to clay liner materials for landfills.

Investigation of strength, durability, and microstructure properties of concrete with waste marble powder as a partial replacement of cement

Purpose Cement plays a significant part in concrete, and with the increasing demand for concrete, cement output varies day by day, allowing production to carbon dioxide emissions. As well as marble processing creates stone slurry and solid discards. These are often dumped irresponsibly on open land, polluting the soil. This improper disposal of marble waste is a major environmental concern. This study aims to propose a sustainable solution for reusing this waste material as a concrete additive. Design/methodology/approach A total of 135 concrete cubes of size 150 × 150 × 150 mm, 54 concrete cylinders of size 150 mm dia. and 300 mm height and 54 concrete beams of size 150 × 150 × 700 mm were cast. The replacement was 0%, 2.5%, 5%, 7.5%, 10%, 12.5%, 15%, 17.5% and 20% by weight of cement with marble dust to create M30 concrete with a water-cement ratio of 0.45. The test was performed to find the compressive strength (CS), flexural strength (FS) and split tensile strength. Also, durability tests like rapid chloride penetration test (RCPT), acid attack, ultrasonic pulse velocity (UPV) and water permeability test were performed. Findings After 7 and 28 days of curing, it was found that replacing 5% of cement with marble powder led to an initial strength improvement of up to 25% for both curing periods. However, further increases in marble dust resulted in an inconsistent decrease in strength for all the mixtures. Also, durability properties like acid attack test, water permeability test and RCPT, showed good performance at the optimum percentage of waste marble powder (WMP) as cement replacement. The microscopic analysis revealed a denser pore structure at lower WMP replacement levels, likely due to the powder filling in gaps. Originality/value This study reveals that by substituting 5% (optimum) of cement with WMP, there was CS improvement up to 8.4% and 17% for both 7 and 28 days of curing. WMP is typically finer than cement particles and fills the voids in the concrete more effectively, resulting best performance at optimum percentage against RCPT, UPV, acid attack and water permeability.

The Basic Rheological Properties of LDPE Modified Bitumen

Various polymers have widely known in its capability in enhancing rheological properties of bitumen for various pavement applications. Many polymer types have been used in studies, where the properties of the final product of the polymer modified bitumen (PMB) are different, depending on the used polymers. LDPE or Low-Density Polyethylene are one of widely studied polymers in bitumen modification that exhibit higher bitumen's viscosity, perform better in resisting deformation under heavy loads, and tend to show better integrity in high temperatures. LDPE-modified bitumen also believed to enhance elasticity, allowing a potentially better resistance to cracking due to ability to recover at low strain. Many studies also stated the improvement of LDPE-modified bitumen against thermal and mechanical stress, better adhesion to aggregates in asphalt mixtures, and various promising result for overall durability and longevity of pavement. This study explains basic rheological properties of LDPE-modified bitumen prepared by high shear mixing and specified preparing methodologies. Five variables of %modifications were used: 2%, 4%, 6%, 8% and 10% of bitumen weight. Ring and Ball softening point, Penetration test and rotating spindle viscometry were done to understand the rheological changes of the modified bitumen compared to unmodified bitumen control. For further understanding the behaviour, two types of LDPE were used: virgin LDPE and recycled LDPE. The study shows interesting noticeable differences between the two used LDPE polymers, allowing further proposed studies in this field.

Application and Evaluation of Cone Penetration Testing for Determining Internal Friction Angle in Composite Subgrade Cushion Layer

Application and Evaluation of Cone Penetration Testing for Determining Internal Friction Angle in Composite Subgrade Cushion Layer

Sand State Parameter from CPT

A cone penetration test (CPT) based procedure is proposed to determine the in-situ density and state parameter (ψ) of cohesionless soils. To date several correlations have been developed to estimate ψ from CPT results, but most correlations are based on limited calibration testing and/or require soil constitutive parameters from laboratory shear tests. The new framework is based on a limit pressure calculated using cavity expansion theory and a semi closed-form solution that is scaled to existing calibration chamber data using a chamber shape factor. This enables estimation of ψ directly from CPT results, which makes it practical and theoretically sound. This facilitates determining ψ for use in flow failure assessment procedures for dams and embankments.

CIPHER: Cybersecurity Intelligent Penetration-Testing Helper for Ethical Researcher

Penetration testing, a critical component of cybersecurity, typically requires extensive time and effort to find vulnerabilities. Beginners in this field often benefit from collaborative approaches with the community or experts. To address this, we develop Cybersecurity Intelligent Penetration-testing Helper for Ethical Researchers (CIPHER), a large language model specifically trained to assist in penetration testing tasks as a chatbot. Unlike software development, penetration testing involves domain-specific knowledge that is not widely documented or easily accessible, necessitating a specialized training approach for AI language models. CIPHER was trained using over 300 high-quality write-ups of vulnerable machines, hacking techniques, and documentation of open-source penetration testing tools augmented in an expert response structure. Additionally, we introduced the Findings, Action, Reasoning, and Results (FARR) Flow augmentation, a novel method to augment penetration testing write-ups to establish a fully automated pentesting simulation benchmark tailored for large language models. This approach fills a significant gap in traditional cybersecurity Q&A benchmarks and provides a realistic and rigorous standard for evaluating LLM’s technical knowledge, reasoning capabilities, and practical utility in dynamic penetration testing scenarios. In our assessments, CIPHER achieved the best overall performance in providing accurate suggestion responses compared to other open-source penetration testing models of similar size and even larger state-of-the-art models like Llama 3 70B and Qwen1.5 72B Chat, particularly on insane difficulty machine setups. This demonstrates that the current capabilities of general large language models (LLMs) are insufficient for effectively guiding users through the penetration testing process. We also discuss the potential for improvement through scaling and the development of better benchmarks using FARR Flow augmentation results.