Granular Materials Under Shock and Blast Loading

This volume discusses the fundamental dynamic behaviour of granular materials, in particular cohesionless sand, when subjected to shock and blast wave loading. The contents of the book are mainly divided into three parts based on the type of loading imparted to the granular materials: Shock-wave loading (step pulse); Air-blast loading (Friedlander wave); Buried-blast loading. It provides a comprehensive review of the available testing methods, along with the necessary diagnostic measurements for material characterization, making it useful for researchers working in the area of blast protection and Impact engineering

Probabilistic assessment of surface level seismic hazard in India using topographic gradient as a proxy for site condition

This paper presents spatial variation of seismic hazard at the surface level for India, covering 6–38° N and 68–98° E. The most recent knowledge on seismic activity in the region has been used to evaluate the hazard incorporating uncertainties associated with the seismicity parameters using different modeling methodologies. Three types of seismic source models, viz. linear sources, gridded seismicity model and areal sources, were considered to model the seismic sources and different sets of ground motion prediction equations were used for different tectonic provinces to characterize the attenuation properties. The hazard estimation at bedrock level has been carried out using probabilistic approach and the results obtained from various methodologies were combined in a logic tree framework. The seismic site characterization of India was done using topographic slope map derived from Digital Elevation Model data. This paper presents estimation of the hazard at surface level, using appropriate site amplification factors corresponding to various site classes based on VS30 values derived from the topographic gradient. Spatial variation of surface level peak horizontal acceleration (PHA) for return periods of 475 years and 2475 years are presented as contour maps

Evaluation of seismic hazard parameters for Bangalore region in South India

In this paper, seismic hazard parameters are evaluated and presented for Bangalore region following the different methods such as Gutenberg-Richter (G-R) recurrence relation and maximum likelihood procedure and data sets. The seismic data have been collected from various sources for area covering a radius of 350 km around Bangalore. A complete analysis has been carried out using the method as proposed by Stepp. From the analysis it was found that the seismic data is homogenous for the last four decades irrespective of magnitude. The value of seismic hazard parameter \u27b\u27 was estimated for complete data by using G-R relation. Completed data do not include the maximum reported magnitudes of 5 and above in this region. Hence b value has been evaluated by considering mixed data magnitude range of 3.5 to 6.2 and 4 to 6.2 using Gutenberg-Richter recurrence relation. In addition seismic hazard parameters such as, \u27b\u27 of the magnitude- frequency relationship, R the mean return period and Mmax maximum regional magnitude is evaluated based onmaximum likelihood procedure. It has been observed that the comparative analysis using complete and mixed data, gives comparable values. The \u27b\u27 values presented in this paper are higher than the earlier reported values

Use of industrial waste materials for 3D printing of sustainable concrete: A review

This paper provides a comprehensive review of the utilization of industrial wastes in 3D concrete printing processes. Concrete 3D printing processes are introduced, highlighting the need for unique material requirements. The literature on the different wastes that have been used for producing 3D printable mixtures is reviewed, including waste generation, material properties, and the roles of these materials in improving the fresh properties needed for concrete printing. Factors affecting successful utilization of these waste materials in 3D printable concrete are discussed in addition to their environmental impacts. This paper underlines the positive impacts of using industrial wastes for improving the sustainability of 3D printable concrete. It is expected that printable concrete formulations containing high volumes of industrial waste (and chemical admixtures) can be developed to improve the sustainability index of this emerging construction technique. [Display omitted] oCritical review of 3D printed concrete made with industry waste is presented.oFactors affecting successful utilization and effects of these waste materials are discussed.oSustainability assessment of 3D printable mixes is presented.oThe challenge is to produce high performance 3D printable concrete using high volume of industry waste

Effect of frequency and amplitude on dynamic behaviour, stiffness degradation and energy dissipation of saturated cohesive soil

Cohesive soil undergoes cyclic softening when experiences the dynamic loading conditions. Evaluation of strength loss under such loading conditions is essential for soil stability analysis. The present study investigates the cyclic response, stiffness degradation behaviour with number of loading cycles and cumulative energy dissipation characteristics within the soil mass of cohesive geomaterial. Slurry consolidated specimens of saturated cohesive soil were prepared to perform several series of strain controlled cyclic triaxial tests at varying loading frequency and axial strain amplitude under consolidated and unconsolidated testing conditions. A great influence of loading amplitude and frequency was observed on the hysteresis response and dynamic properties of cohesive soil under consolidated and unconsolidated testing conditions. Amount and rate of cyclic stiffness degradation in addition to cumulative dissipated energy were also evaluated at different dynamic loading (amplitude and frequency) and testing conditions (consolidated and unconsolidated). Cyclic strength and stiffness of saturated cohesive soil were obtained to be higher under consolidated testing conditions as compared to unconsolidated. A large decay in cumulative dissipated energy was observed with the increment in loading cycles.by Saloni Pandya and Ajanta Sacha