Field Investigation on Ground and Structural Vibrations During Prototype Pile Driving

As the land is very precious in urban areas and coastal regions, many structures are built in close proximity. When the soil is weak and heavy loads are to be carried, pile foundation is adopted for such structures. The impact caused by pile driving is a potential hazard to neighbourhood structures. Berthing structures are constructed using piles and the effect of pile driving on already installed adjacent piles is important. To predict the effect of pile driving on neighbourhood piles, measurement of ground and structural vibrations during prototype pile driving was carried out at a site in the city of Chennai, India. The soil at the site up to a depth of 19 m is mainly fine to medium sand. A driven cast in-situ pile of 600 mm diameter (D) was driven up to a depth of 15.8 m. The 25mm thick mild steel (M.S) tube casing is driven by 4.1t hammer with a drop height of 2.5m. During the pile driving, for every blow of hammer, the acceleration of the ground at various distances 5D, 8.33 D and 25 D from the pile are measured. Piezoelectric acceleration transducers, power amplifiers and taper recorder are used for measurement. The time history of vertical and horizontal ground accelerations as well as time history of vertical acceleration of an already installed pile at a distance of 6.25 m was analysed using PC based data acquisition systems. The time-histories and spectrum of ground and structural accelerations are presented

Prototype Piling in Soft Clay — A Case Study of Ground Vibrations: Field Measurement

Ground vibrations are generated either by natural phenomena or by human activities. Among the natural phenomena, earthquake is the principal source of ground vibrations of most interest. Ground vibrations generated by human activities are called manmade vibrations and these vary greatly in intensity depending on the particular source of vibration. The seismic waves associated with man-made vibrations propagate in the ground and inevitably interact with structures that are above-ground or underground. This interaction induces vibrations in the structure and, in extreme cases, affect its serviceability and integrity seriously. Still, there is no method to quantify the levels of piling vibration. Estimation of amplitudes and frequencies of vibration are based on experience and site testing. Therefore, in order to characterize the ground vibration due to piling, field measurement of ground vibration during prototype pile driving in soft clay was carried out. This paper presents the details of field measurement, instrumentation, collection of vibration data, acquisition and processing of data using PC-based data acquisition system made during the pile driving. The measurement of ground and already installed pile vibrations during prototype pile driving at a construction site in Chennai was carried out. The soil at this site is loose soft clay. The pile was of the type driven casing cast-in-situ pile of 500mm (OD) diameter. The depth of penetration of the pile was 13.25m. A 4 tonne hammer with a drop height of 1m drove the 25mm thick Mild Steel (MS) tube casing. During driving, ground acceleration was measured at a distance of 5D and 25D, where D is the diameter of pile, from the centre of pile. The vertical acceleration of an already installed pile situated at a distance of 37D from the driven pile were recorded. Piezoelectric acceleration transducers, power amplifiers, and tape recorder were used for the measurement. Acceleration signals were recorded using TEAC recorder. The recorded signals were processed using PC-based Data Acquisition System with DASYLAB software. The response time-histories and spectra of ground vibrations are presented and discussed

Parallel network file systems using authenticated key exchange protocols

The keyestablishment for secure many-to-many communications is very important nowadays. The problem is inspired by the proliferation of large-scale distributed file systems supporting parallel access to multiple storage devices. In this, a variety of authenticated key exchange protocols that are designed to address the issues. This shows that these protocols are capable of reducing the workload of the metadata server and concurrently supporting forward secrecy and escrow-freeness. All this requires only a small fraction of increased computation overhead at the client. This proposed three authenticated key exchange protocols for parallel network file system (pNFS). The protocols offer three appealing advantages over the existing Kerberos-based protocol. First, the metadata server executing these protocols has much lower workload than that of the Kerberos-based approach. Second, two of these protocols provide forward secrecy: one is partially forward secure (with respect to multiple sessions within a time period), while the other is fully forward secure (with respect to a session). Third, designed a protocol which not only provides forward secrecy, but is also escrow-free

Image sharing privacy policy on social networks using A3P

User Image sharing social site maintaining privacy has become a major problem, as demonstrated by a recent wave of publicized incidents where users inadvertently shared personal information. In light of these incidents, the need of tools to help users control access to their shared content is apparent. Toward addressing this need an Adaptive Privacy Policy Prediction (A3P) system to help users compose privacy settings for their images. The solution relies on an image classification framework for image categories which may be associated with similar policies and on a policy prediction algorithm to automatically generate a policy for each newly uploaded image, also according to user’s social features. Image Sharing takes place both among previously established groups of known people or social circles and also increasingly with people outside the users social circles, for purposes of social discovery-to help them identify new peers and learn about peers interests and social surroundings, Sharing images within online content sharing sites, therefore, may quickly lead to unwanted disclosure. The aggregated information can result in unexpected exposure of one’s social environment and lead to abuse of one’s personal information

Measurement of Vibration in Berthing Structure During Underwater Rock Blasting

Blasting, in particular underwater rock blasting is the most challenging and least understood source of vibration, which may cause considerable damage to the safety of the adjacent buildings and structures and including berthing structures. Though the blast-induced vibration is best controlled by specification of blasting procedures, it is very essential to measure and monitor the blast-induced vibration of the adjacent structures to access its safety. This paper discusses the measurement and monitoring of underwater blast induced vibration on the berthing structure (berth No.8) at Tuticorin in southern part of India. The vibration is recorded using three acceleration transducers mounted on the deck slab of berthing structure and monitored using a data efficiency system consisting of HBM make multi channel carrier frequency amplifier system with digital storage oscilloscope. It is observed that the peak vertical acceleration is much higher than the longitudinal and lateral peak acceleration, because of vibration of deck slab along with frequency of ground excitation. The peak particle velocity (PPV) is obtained from the time history of acceleration by simple integration. From the spectral analysis, the predominant frequency is found as 26 Hz. For this frequency the allowable PPV value is established from various standards as 25mm/sec. The measured PPV values fro all blasts (31 nos) are well below the limit of allowable PPV value, except in few blasts, which shows the berth is safe against underwater blast induced vibration. Pre and post crack survey also proves that there is no considerable damage to the berthing structure

Strengthening of Load Bearing Masonry Wall Panels with Externally Bonded Precast Textile Reinforced Concrete Laminate

241-245Textile Reinforced Concrete (TRC) has gained worldwide popularity as a strengthening material for masonry structures in the recent years. As of today, the application of TRC for masonry strengthening is either by cast-in-place methodology or by spraying method. The present work is a first-of-its kind study, which explores the feasibility of using externally bonded precast TRC laminate for strengthening of load bearing brick masonry wall panels. The binder used in TRC itself is used as adhesive for adhering the TRC laminate to masonry wall panels. Experimental investigations were carried out on unstrengthened and strengthened brick masonry wall panels under axial compression and combined axial compression and shear loading. The influence of TRC strengthening system is assessed by examining the performance indicators such as strength, stiffness and deformation. Based on the investigations, the use of externally bonded precast TRC laminate is found to be a feasible solution to strengthen brick masonry walls to have the required structural adequacy

Strengthening of Load Bearing Masonry Wall Panels with Externally Bonded Precast Textile Reinforced Concrete Laminate

Textile Reinforced Concrete (TRC) has gained worldwide popularity as a strengthening material for masonry structures in the recent years. As of today, the application of TRC for masonry strengthening is either by cast-in-place methodology or by spraying method. The present work is a first-of-its kind study, which explores the feasibility of using externally bonded precast TRC laminate for strengthening of load bearing brick masonry wall panels. The binder used in TRC itself is used as adhesive for adhering the TRC laminate to masonry wall panels. Experimental investigations were carried out on unstrengthened and strengthened brick masonry wall panels under axial compression and combined axial compression and shear loading. The influence of TRC strengthening system is assessed by examining the performance indicators such as strength, stiffness and deformation. Based on the investigations, the use of externally bonded precast TRC laminate is found to be a feasible solution to strengthen brick masonry walls to have the required structural adequacy

Investigation on behaviour of reinforced geopolymer concrete slab under repeated low velocity impact loading

ABSTRACT: Geopolymers are a novel class of materials that are formed by the polymerisation of silicon, aluminum, and oxygen species to form an amorphous 3-D framework structure. Concrete made out of these binder system possess several advantages compared to conventional ordinary Portland cement concretes (OPCCs). Substantial research work has been reported on the impact behaviour of reinforced concrete structural elements whereas similar studies have not been reported on GPCs. This paper describes the experimental and numerical investigation on the behaviour of reinforced GPC slabs under repeated impact loading. The aim is to study the impact behavior of reinforced GPC slabs with and without steel fibers and compare with that of OPCC slabs. The overall dimensions of the GPC slab are 1m x 1m, with 60mm thickness. Finite element modeling of slab was also carried out using ANSYS software. The Solid 65 element and link 8 elements were used to model the concrete slab and Reinforcement respectively. Displacement boundary conditions are applied at the supports. The measured impact load time history is used to excite the structure. Transient dynamic analysis was carried out. The response was obtained in terms of deflection time histories. The peak acceleration of analytical studies showed a pattern similar to that obtained from experimental results. The failure crack pattern of plain and steel fibre reinforced slabs predicted by Finite Element analyses are compared with experimental results. The studies emphasize that by proper design, GPCC can be used in lieu of OPCC for structural components subjected to low velocity impact

Evaluation of the Cytotoxic Activity and Anti-Migratory Effect of Berberine–Phytantriol Liquid Crystalline Nanoparticle Formulation on Non-Small-Cell Lung Cancer In Vitro

Non-small-cell lung cancer (NSCLC) is the most common form of lung cancer, which is a leading cause of cancer-related deaths worldwide. Berberine is an isoquinoline alkaloid that is commercially available for use as a supplement for the treatment of diabetes and cardiovascular diseases. However, the therapeutic benefits of berberine are limited by its extremely low bioavailability and toxicity at higher doses. Increasing evidence suggests that the incorporation of drug compounds in liquid crystal nanoparticles provides a new platform for the safe, effective, stable, and controlled delivery of the drug molecules. This study aimed to formulate an optimized formulation of berberine–phytantriol-loaded liquid crystalline nanoparticles (BP-LCNs) and to investigate the in vitro anti-cancer activity in a human lung adenocarcinoma A549 cell line. The BP-LCN formulation possessing optimal characteristics that was used in this study had a favorable particle size and entrapment efficiency rate (75.31%) and a superior drug release profile. The potential mechanism of action of the formulation was determined by measuring the mRNA levels of the tumor-associated genes PTEN, P53, and KRT18 and the protein expression levels with a human oncology protein array. BP-LCNs decreased the proliferation, migration, and colony-forming activity of A549 cells in a dose-dependent manner by upregulating the mRNA expression of PTEN and P53 and downregulating the mRNA expression of KRT18. Similarly, BP-LCNs also decreased the expression of proteins related to cancer cell proliferation and migration. This study highlights the utility of phytantriol-based LCNs in incorporating drug molecules with low GI absorption and bioavailability to increase their pharmacological effectiveness and potency in NSCLC.</jats:p