Number Of Piles Research Articles

A privacy protection scheme to resist ring selection attack in peer-to-peer double auction V2V electricity transaction for charging stations

With the development of Electric Vehicles (EVs), the number of public charging piles cannot meet the immediate charging needs of EV users sometimes. The charging stations provide flexible electricity transaction schemes for users by managing charging piles and Vehicle-to-Vehicle (V2V). Users can freely choose transaction partners and submit transaction plans to multiple charging stations. The mobility of EVs results in users randomly selecting rings multiple times, which may cause them to appear in different rings. Attackers can link multiple transaction plans and infer user privacy information. The leakage of transaction information may threaten the fairness of transactions. Aiming at the above situations, a privacy protection scheme to resist ring selection attack in Peer-to-Peer double auction V2V electricity transaction for charging stations is proposed. Firstly, the ring signcryption algorithm is improved to resist ring selection attack. Secondly, a real identity verification algorithm is designed to track malicious users. Theoretical analysis proves that the security of the proposed privacy protection scheme. The elliptic curve point multiplication is used in the scheme to improve computational efficiency. Experiments show that this scheme has low computational and communication costs. Verification cost increases slowly with the increase of the number of ring members.

Improvement the bearing capacity of the soil which is supporting the shallow foundation by using bored short micro-piles

In this paper , concrete micro-piles were used to improve the bearing capacity of the soil which is supporting the shallow foundation by using groups of (4; 6 and 9)bored short micro-piles which have, (D=0.125m and D=0.1m), and length to diameter ratio (L/D) equal to (6; 10 and 12) respectively. To calculate the bearing capacity of the micro-piles,(Tomlinson) and (Lamda) methods were used; also the soil properties were taken from Al-Muthana airport,(Al-Qyssi,2001) [1]. The results show that; increasing the number of piles and/ or the diameters and lengths; and the interaction between the bearing capacity of the shallow foundation with the bearing capacity of the pile group which leads to increasing the strength against the external loads; and the maximum bearing capacity was, when 9 piles with (L/D=12) was used. The improving ratio in the bearing capacity was (90%) compared with the bearing capacity of a (1×1) m shallow foundation without any piles. The results show that, the Tomlinson method of analysis produce lower results than the Lamda method by a ratio of (2-6) %. The results show also that the use of bored short micro-piles with (D=0.125m); (L/D=12) and number of 4-piles better than the (9) bored short micro-piles which have (D=0.1m).

Investigation of new confined concrete-filled aluminum tube piles: Experimental and numerical approaches

This research aims to introduce and test a Confined Concrete-Filled Aluminum Tube Pile (CCFAT) as an innovative composite pile that embodies a distinctive amalgamation of favourable material characteristics. Experimental tests were carried out to achieve this goal by analysing the vertical and lateral responses of various configurations and slenderness ratios (Lm/D) (ranging from 10 to 20) of CCFAT piles. As a reference group, two traditional piles were also manufactured and tested under identical conditions for comparison purposes. Additionally, the finite element approach was applied to validate the experimental results. The findings indicated that CCFAT piles have either higher or at least equivalent ultimate vertical capacity to that of reference piles. Additionally, the results proved the superior ultimate lateral capacity of the CCFAT piles compared to the reference ones. The results also showed a constant maximum bending moment dept in the CCFAT piles with a Lm/D ratio of 10, with a slight increase observed for CCFAT with a Lm/D ratio of 20 under lateral loading, which could be attributed to the rigidity of the CCAFT piles. Moreover, the outcomes of the finite element analysis indicated that both ultimate vertical and lateral capacities improve with the increase in the number of piles. The sensitivity analysis showed that the dilatancy angle plays the most important role in determining the vertical capacity of the piles, while the lateral capacity was significantly determined by the internal friction angle. Finally, fitted charts were produced and validated in this study to help researchers estimate the ultimate vertical and lateral capacities of CCFAT piles depending on the stiffness of the pile groups.

Numerical tests on dynamic response of pile-supported reclaimed embankment for high-speed railway in saturated soft ground using soil–water coupling elastoplastic FEM

High-speed train (HST) running in the saturated soft ground induces significant vibration that may threaten the running safety and serviceability of high-speed railway (HSR). Extensive studies have been conducted on the dynamic responses of HSR, yet, the soil–water coupling and plastic behavior in the saturated soft ground are rarely considered, and thus the build-up of excess pore water pressure (EPWP) and displacement cannot be accurately calculated. In this study, 2D soil–water coupling elastoplastic FEM was employed to investigate HST induced vibration in the pile-supported embankment using FE code called DBLEAVES. Dynamic soil stress, EPWP, acceleration and displacement under different cases were numerically analyzed in detail. Numerical tests confirm that liquid phase in soft ground plays important influence on the dynamic responses that vertical acceleration and displacement will be overestimated while the horizontal acceleration and displacement as well as EPWP will be underestimated if soil–water coupling is not considered. Single-phase analysis also exaggerates the acceleration attenuation and underestimate the vibration amplification in soft ground. The existence of piles can induce significant soil arching effect in the embankment, the distributions of vertical acceleration and EPWP are partitioned sharply by the piles while vertical displacement in soft ground becomes more uniform along the depth direction within the pile reinforced area. The existence of piles also induces stronger vibration beneath the pile end so that larger EPWP is generated below the pile end than around the pile body. The main influence area due to HST vibration for pile-supported embankment is overall 20 m away from the centerline of HSR track, therefore, it is reasonable to improve the ground by properly increasing the number of pile within this area. When the number of pile is determined, increasing the length of pile or reducing the pile spacing are two effective ways to mitigate the dynamic response.

Fasting horses perioperatively decreases manure production and increases time to manure output postoperatively: a controlled randomized trial.

To compare 3 perioperative feeding regimens and their effect on anesthetic complications, manure output, and colic proportion in healthy horses. 45 horses presenting for elective orthopedic procedures were randomly assigned to 1 of 3 groups: not fasted (NF; continuous access to hay perioperatively), fasted muzzled (FM; 10-hour preoperative fast with slow refeeding postoperatively and muzzle placement), or fasted not muzzled (FNM; same as FM without muzzle placement). Anesthetic protocol was standardized. Outcomes compared between groups included anesthesia time, arterial oxygenation, duration of hypotension, perioperative manure output, time to first passage of manure postoperatively, pain scores, and colic proportion. Comparisons were made with a mixed model and Fisher exact test with statistical significance considered at P ≤ .05. No differences were seen in pain scores, oxygenation, hypotension, or colic between groups. Groups FM and FNM had a significantly greater mean reduction in postoperative manure weight (-81% and -70%; P = .003) and number of manure piles (-63% and -55%; P = .005) compared to group NF (-39% and -22%; P < .001; weight and piles, respectively). Mean ± SD minutes to passage of manure postoperatively was significantly shorter in group NF (238 ± 13 minutes) than groups FM (502 ± 174 minutes; P < .001) and FNM (444 ± 171 minutes; P = .003). Horses with continuous access to hay prior to and following recovery from anesthesia passed more manure and passed manure sooner after surgery than their fasted counterparts without detrimental effect on anesthetic parameters and postoperative complications. Continuous access to hay perioperatively supports manure production in healthy horses without increase in anesthetic complications.

Response of group piles subjected to coupled vertical-eccentric lateral-seismic loads

In seismic prone regions, analyzing loaded pile groups can be challenging because of limitations in conventional design methods and the inability of small-scale laboratory tests to accurately replicate the real behavior. Studying how pile group response is affected by the combined impact of vertical, concentric, and seismic loads is challenging. One of the limitations pertains to the intricacy of scaling up experiments, particularly in creating large-scale laboratory models. Thus, a numerical analysis may be appropriate for capturing the response. This study aimed to understand the pile group response in dense sand subjected to vertical, eccentric lateral, and seismic loadings via a large-scale 3D nonlinear finite element model. The validation results indicate that the numerical approach accurately predicts the behavior of pile groups in dense sand. Then, two different layouts of pile groups are analyzed under various loading scenarios on the basis of the recorded data from the El Centro earthquake. The results revealed that the number and arrangement of piles significantly affect the induced settlement. Compared with the 5-pile groups, the 3-pile groups presented higher maximum bending moments under vertical loading. However, the response of the 5-pile groups varied, as they experienced higher bending moment values without vertical loading. The peak lateral soil pressures were higher in the 3-pile groups. Some significant variations appeared in the induced torque resistances when the 5-pile groups were compared with the 3-pile groups. This study demonstrated the reliability of the used numerical approach for analyzing the response of pile groups in dense sand, as an alternative to laboratory test models.

Numerical modeling and validation of dike-induced water flow dynamics using OpenFOAM

ABSTRACT The basic purpose of the present research is to numerically elucidate the flow around a single dike in four different geometric configurations (CN: no cylinders, C5: 5 cylinders, C10: 10 cylinders, C15: 15 cylinders), under conditions of a constant flow rate and subcritical flow. This involved substituting the impermeable dike with varying numbers of piles to validate the observed experimental flow patterns, particularly the conditions leading to reverse flow formation. OpenFOAM, an open-source algorithm, was utilized for the simulation, incorporating the volume of fluid (VOF) method. Accurately depicting the reverse flow formation with minimal numerical diffusion, a strategy involving multizone meshing and the application of mesh refinement zones was utilized. These refinements were particularly focused on the section between 1.8 m and 2.2 m within the numerical domain. The water surface profile in front section of the dike and the averaged velocity at five different locations, which were then compared with the numerical results. The numerically predicted streamwise velocity showed a percentage error ranging between 0.5% and 4.5%. The numerical results from this study are pivotal in dike design, aiming to mitigate accelerated wear during flood events and to protect both the dike head and the adjacent bank from high energy flow failures.

Study on Deformation Control of Road-Deep Foundation Pit Passing under Elevated Subway Bridge

This paper focuses on the application of pile foundation underpinning technology in a deep foundation pit of a subway Viaduct Project in Beijing. The study aims to address the engineering characteristics of the project, including a large number of new piles, a wide span of underpinning abutment, a long length of deep foundation pit, and a wide range of influences. This research utilizes field monitoring and numerical simulation methods to investigate the pile foundation underpinnings. The impact and management of road-deep foundation pit construction are considered, as well as their combined effect on subway viaducts and track structures. The primary accomplishments are as follows: (1) By analyzing the data from on-site deformation monitoring, it is evident that the pier exhibits maximum vertical deformation and maximum transverse deformation at the same location. The measuring locations are specifically situated on Pier 7# at the pile foundation underpinning. The maximum vertical and transverse deformations of the track are directly proportional to the maximum deformation of the pier. (2) By comparing the numerical simulation results with the field monitoring data, it is observed that although there is some discrepancy between the two, the deformation trend is largely consistent. This suggests that the numerical simulation analysis method is effective in reflecting the deformation of the bridge and track. (3) Through the numerical model and changing the values of the retaining structure parameters, the sensitivity of the pier deformation near the road foundation pit to the retaining structure parameters is systematically analyzed. The sensitivity of the pier deformation to the foundation pit parameters is as follows: the embedded depth insertion ratio of the retaining pile &gt; the diameter of the retaining pile &gt; the pile spacing.

Analysis of the effectiveness of the use of short piles as part of a columnar pile foundation

The realization of the operation of the grid and piles as a part of the columnar pile foundation, depending on the length of the piles, the method of arranging the piles, the distance between the piles and the type of soil with a constant number of piles, has been studied. The degree of implementation of the load-bearing capacity of the piles and the degree of implementation of the grid work as part of the pile foundation were analyzed. To solve the tasks set in this work, mathematical modeling by the finite element method of the joint operation of the pile foundation elements with the soil base and the separate operation of the pile and grid as a shallow foundation was performed in the "Plaxis 3D Foundation" software complex. It was established that the implementation of the load-bearing capacity of piles in the composition of the foundation with a large distance between the piles is much better. The length of the piles also affects the degree of their implementation. When the length increases, the bearing capacity of the piles is realized less. The greatest implementation of the load-bearing capacity of piles in the composition of the foundation is observed for short piles. The realization of the pressure under the sole of the grid with an increase in the pitch of the piles also improves, the realization of the load-bearing capacity of the grid is from 8 to 50%, which allows to raise the load-bearing capacity of the foundation. For sandy and clay soils, the nature of the redistribution of forces between the elements of the columnar pile foundation is similar. For foundations made of drilled piles, the degree of realization of pressure under the sole of the grate, as well as the degree of realization of the load-bearing capacity of the piles, is higher than for foundations made of driven piles. The guiding factor is the length of the piles. The economic efficiency of the transition in homogeneous soils from a bush made of long piles with a standard minimum step to a bush made of short piles with an increased distance between the piles was investigated. By taking into account the joint operation of piles and grid, a bush made of short piles with larger dimensions of the grid provides the same bearing capacity as a bush made of long piles with a compact grid. Despite the significant increase in the volume of concrete grating and the number of fittings with an increase in the pitch of the piles, cost savings on the cost of piles provide an economic effect of using bushes from short piles with wide gratings up to 35%.

Propagation attenuation of elastic waves in multi-row infinitely periodic pile barriers: A closed-form analytical solution

Periodically arranged media exhibit attenuation zones for elastic waves, and the related periodic structures play a crucial role in the design of seismic isolation and vibration mitigation. From the perspective of wave theory, this paper presents a closed-form analytical solution for the propagation attenuation of elastic waves through infinitely periodic, multi-row pile barriers. The innovative approach begins by deriving the extended Graf’s addition theorem to transform wave potentials across arbitrary coordinate systems, overcoming the constraints of traditional formulas that limit pile centers to linear configurations. Subsequently, it completes the wave function expansion by utilizing the phase differences in the frequency domain of wave fields around different periodic elements, thus skillfully integrating the effects of incident and scattered wave fields. For the first time, this study delivers exact expressions for the scattering of various types of plane waves (SH, SV, and P) by multi-row pile barriers with an infinite periodic array, addressing the complexities of large pile numbers in previous theoretical studies. The proposed solution increases computational efficiency by tens of times and markedly reduces the majority of resource usage, improving the analysis of complex vibration isolation systems involving numerous piles. Building on the accuracy verification and convergence analysis, several numerical examples are conducted to explore the effects of pile row, pile spacing, and pile arrangement on the propagation attenuation. The findings elucidate the mechanisms driving vibration reduction design using periodic wave barrier, furthering its application in engineering structures.

Stabilitas Paving Block Menggunakan Plastik PET (Polyethylene Terephthalate) Dengan Tambahan Serat Bendrat

Plastic waste is one of the most complex problems especially in the Parepare region. Recycling of plastic waste is rare, so the number of garbage piles increases annually. Paving block made from PET plastic waste is one form of effort to reduce the accumulation of plastic waste. The non biodegradable properties of polyethylene cause the plastic aggregate in paving block not to be easily crushed, so it can keep paving block density over a long period of time. The purpose of this study was to determine the stability and compressive strength of paving blocks made of plastic with a variation of 50% PET, 75% PET and 100% PET with bendrat wire fiber, and to find out what the proportion of plastic and sand is in the paving block mixture, which results in optimal compressive strength. The method used is the experimental trial and error method, by experimenting directly in the laboratory. The experiment in question is to make comparisons of the variables studied, so as to produce conclusions that are correlated with the variables studied. From several variations of the planned pet percentage, only 1 variation has stability, namely the 50% PET variant, and the most optimal proportion of plastic and sand is found at 50% PET. The compressive strength obtained is 14.72 MPa for the cube test object and for the paving block specimen it has a compressive strength of 10.16 MPa.

Pile–Soil Interaction during Static Load Test

Abstract This study highlights the possibility of determining the shear stress distribution along the skin of a pile, which represents skin resistance. Geotechnical engineering is plagued by the challenge of designing appropriate piles as a sufficient foundation construction while being economically justified solution. Static load testing facilitates verification if the pile satisfies these requirements. In most cases, the pile skin resistance is undervalued. This study first introduces the general approach based on static load test results using an appropriate mathematical approach in the presence of linear, vertical shear stress distribution boundary conditions as well as phenomena such as pile shortening and Kirchhoff's principle. Moreover, a scientific approach for pile compression and shear stress distribution is presented. Further, the study expands upon previous work by applying mathematical calculus to displacement piles. The promising results indicate that further work on greater number of piles may lead to a better understanding of pile–soil interaction and a more accurate design process.

Effects of disc overhang diameter on the uplift bearing capacity of new-type concrete expanded-plate pile groups

The disc overhang diameter can significantly affect the uplift bearing capacity of new concrete expanded-plate pile groups, affecting their design and practical applications. Accordingly, this effect was investigated considering the failure laws of the soil surrounding various pile types and groups. Based on the uplift bearing capacities of single and double piles, a finite element simulation was adopted to establish models for the four-, six-, and nine-pile groups. The relationship between the disc overhang diameter and uplift-bearing capacity of each pile group was explored: as the disk overhang diameter increased, the uplift-bearing capacities of the pile groups increased; however, this relationship is nonlinear. The optimal disc overhang diameter was determined as 1.5–1.75 times the pile diameter. For a constant disc overhang diameter, corner piles have a greater uplift bearing capacity than side piles in the six-pile group, and a greater uplift bearing capacity than the side and center piles in the nine-pile group. Thus, the pile-group effect depends on the pile position. The uplift bearing capacity did not increase linearly with the number of piles, and the average uplift bearing capacity of a pile in a pile group was less than that of a single pile. Therefore, the uplift bearing capacity of the pile groups decreased as the number of piles increased. The reliability of the simulation was verified via visual testing of a small-scale half-cut pile model.

Multi-objective optimization and evaluation of the building-integrated photovoltaic/thermal-energy pile ground source heat pump system

Building integrated photovoltaic thermal (BIPV/T)-energy pile ground source heat pump (GSHP) system effectively maintains the soil thermal balance and improves the photovoltaic efficiency by recovering the waste solar heat from the BIPV/T collector to charge the ground. However, due to the strict carbon emission restriction and economic consideration for system application, multi-objective optimization should be implemented for the system design to further enhance its overall performance. Therefore, a complete optimization framework is proposed in this paper, which is based on the NSGA-II algorithm and functions by coupling TRNSYS and jEPlus+EA. Using the proposed optimization frame, a comprehensive optimization is conducted for the system, which optimizes five main design variables and adopts the total power consumption (TPC), life cycle climate performance (LCCP), and life cycle cost (LCC) to reflect the system's energetic, environmental, and economic performances. Seven optimization cases are included in the optimization project to identify design schemes that meet all possible proposed performance requirements for the system application. The optimized results show that the system optimization improves its performance greatly compared to the design condition, with a range of 38.03% ∼ 50.05% for the TPC, 24.52% ∼ 25.86% for LCCP, and 56.74% ∼ 61.66% for LCC. The energetic, environmental and economic performances of the system can be maximized by minimizing the TPC to 357.29 MWh in Case 1, LCCP to 596.15 tCO2 in Case 2, and LCC to 17.03 × 104 CNY in Case 3. By breaking down the objective functions, it is found that the heat pump unit holds paramount importance in all aspects of system performance, and the BIPV/T collector proves advantageous in enhancing the system's long-term performance due to its massive electricity generation. Accordingly, one important finding is that it is advisable to incorporate as many BIPV/T collectors as feasible while maintaining soil heat balance. The optimal energy pile number varies among the seven optimization cases, resulting in different heating capacities for the heat pump unit. Research outcomes in this work offer references for designing the energy-pile GSHP system to enhance the penetration of renewable energy into buildings.

Deep Foundation with Driven Precast Concrete Piles and Monitoring with Pile Driving Analyzer PDA

A practical case of deep foundation for an industrial plant in Puerto Natales is presented, using precast reinforced concrete piles that are driven into soft clays (Nspt &lt; 5 blows/ft). Equipment and methods were used for the evaluation of the pile structural integrity and their geotechnical capacity by means of PDA monitoring (Pile Driving Analyzer) during driving. With the results of the PDA test, together with the CAPWAP computational tool, the design hypotheses were verified. During the execution of the project, it was possible to achieve the optimization of the embedment depth and the variation of the required number of piles.

Quantitative Research on New Energy Vehicle Development Based on Multiple Linear Regression

Analyzing the factors influencing the development of China's new energy vehicles is beneficial for understanding the progress of this sector and boosting its growth. This study utilizes gray correlation analysis and a multiple linear regression model to examine the relationship between diverse factors and the progress of new energy vehicles. To identify the primary determinants of new energy vehicle sales, data on pertinent indicators were collected. Initially, seven evaluation indicators affecting the sales of new energy vehicles were identified by reading many literatures. Subsequently, gray correlation analysis was employed to calculate the degree of association between these indicators and new energy vehicles. It was discovered that the gray correlation between the number of public charging piles and the sales of new energy vehicles is 0.922, and the corresponding gray correlations of the remaining six indicators are all 0.7-0.8, which means that the correlation between the indicators and the sales of new energy vehicles is obvious, and all of them are used to establish the multiple linear regression model. The results show that the number of public charging piles has the most significant effect, with a regression coefficient of , which indicates that strengthening the charging infrastructure can effectively promote the growth of its sales.

Fracture mechanics analysis of gas pipeline with circumferential crack under the action of transverse landslide

The whole process of pipeline–soil interactions between a landslide and a gas pipeline was simulated using the strength reduction method. The main purpose is to investigate how pipeline internal pressure, landslide displacement, crack depth ratio (the ratio of crack depth to wall thickness), crack aspect ratio (the ratio of crack depth to crack half-length), and reinforcement with anti-slide piles influence the J-integral of a circumferential crack in the pipeline under landslide impact. The simulation showed that increases in the landslide displacement, crack depth ratio, and pipeline internal pressure led to an increase in the maximum value of the J-integral at the crack leading edge. An increase in the crack aspect ratio reduced the maximum value of the J-integral. In addition, in the process in which the crack shape changed from semi-elliptical to semicircular, there was a critical crack aspect ratio at which the J-integral at the deepest point of the crack was equal to the J-integral at a point on the surface. The study also found that an increase in the number of anti-slide piles affected the location and distribution of the zone of maximum slippage and effectively reduced the maximum von mises stress and the J-integral at the crack tip. However, when the number and cross-sectional size of anti-slide piles exceed a certain threshold, further increasing or enlarging them barely affects the J-integral.

The Effect of Setup Time in Geotechnical Resistance Factor of Driven Steel Piles in Alberta: a Case Study

Determining the bearing capacity of driven steel piles is a critical concern in geotechnical engineering particularly when constructing major structures in oil and gas and infrastructure projects in Alberta. To verify pile capacity, the pile driving analyzer (PDA) and static load tests (SLTs) are widely used. In recent years, PDA testing has become a regular part of pile quality assurance programs on projects and increasingly used as full-scale load tests. Several studies have shown that geotechnical resistance factor (GRF) values can be calibrated with the aim of PDA testing results which can help designers to potentially reduce the number and length of piles. Nevertheless, uncertainty remains regarding the extent to which the GRF value can be optimized following the implementation of the PDA. In this paper, a database of PDA tests and SLTs are compiled from several projects in Alberta, Canada. The primary objective of this study is to assess the impact of time on the recommended GRFs by several codes. To achieve this, the study employs a well-established probabilistic technique known as Monte Carlo Simulation (MCS) to quantify the influence of time, referred to as “setup time”. To enhance the assessment of setup time’s effect, the recorded bearing capacities are collected during two distinct time points: after the completion of pile installation or the end of drive (EOD) condition, and after a specific setup time at the Beginning-of-Restrike (BOR) condition. The results suggest that by taking into account the time impact, GRF values can be optimized, leading to an increase in factored pile resistance and ultimately resulting in a more cost-effective design process for steel-driven piles.

Dynamics Responses of a Block Machine Foundation and a Pile Group Foundation Systems on Stratified Residual Soils in Indonesia by Lumped Mass and Finite Element Methods

This paper presents a comprehensive study of the dynamic responses of machine foundations, both block and pile foundations, on stratified residual soils in Duri and Ulubelu, Indonesia. The evaluation was conducted using two widely recognized methods: the lumped mass method (LMM) and the finite element method (FEM). LMM and FEM were performed by utilizing DYNA and ABAQUS, respectively. The analysis results showed that LMM generally predicted more conservative displacements compared to FEM. This conservatism in predicted displacement was more pronounced for pile group foundations, which are inherently more flexible than block foundations. Additionally, this study found that the resonance frequencies obtained through both analysis methods were not the same. Furthermore, this paper includes a parametric study and presents its results to assess the influence of key factors, i.e., pile cap thickness, pile diameter, number of piles, and vertical dynamic loads, on displacement.

Karaktersasi Bakteri Pengurai Plastik Sintetis Polipropilen dari Sampel Air Laut Studi Kasus dan Potensi Lingkungan

The increase in the number of waste piles in Indonesia has reached 175,000 tons/day or the equivalent of 64 million tons/year. In the health sector, synthetic plastics are used as materials for making packaged medicine bottles and infusion bottles. Polypropylene synthetic plastics are very slow to degrade, making them a major problem in environmental pollution. This study aims to determine the type of bacteria and the ability of bacterial isolates to degrade polypropylene plastics. The research methods used include characterization of bacterial isolates macroscopicly, microscopicly, biochemical tests, then polypropylene synthetic plastic biodegradation tests were carried out during the incubation period of 1 week, 2 weeks, 3 weeks, and 4 weeks using an incubator shaker device. The results of this study obtained 4 bacterial isolates that can decompose polypropylene plastic from seawater samples in Padang City. The results of the isolation of polypropylene plastic bacteria from seawater samples in Padang City ILT-14 bacterial isolate based on macroscopic characteristics. and molecular identification was carried out in the LIPI biotechnology testing laboratory by the 16S rRNA gene deritimization method obtained polypropylene plastic scavenging bacterial species, namely: ILT-14 has similarities with Stenotropomonas Maltophilia. With a 30-day polypropylene plastic decomposer percentage of 10.8%. The difference in FTIR analysis was in the percentage value of carbon group transmission, and the aromatic group decreased. When compared to plastic before it was degraded and there was a decrease in percent. Microscopy Electron Scanning (SEM) Analysis of ILR-14 polypropylene plastic isolate of bacteria isolated is able to break down complex polymers into monomer forms