This study investigated the undrained vertical bearing behaviour of circular skirted mudmat foundations resting on anisotropic marine clays using finite element limit analysis (FELA) incorporating Anisotropic Undrained Shear failure criterion. The effects of mudline undrained shear strength s_u0 , strength gradient k , undrained strength anisotropy ratio r_e , and skirt depth ratio d/D on the ultimate bearing pressure and normalized bearing capacity factor N_su are systematically examined. The results reveal strong nonlinear interactions between skirt embedment, strength non-homogeneity, and anisotropy. N_su increased significantly with increasing d/D and k , especially under low s_u0 , while higher r_e enhanced vertical resistance. The numerical database was used to train supervised regression models, including linear regression, support vector regression, regression trees, wide neural networks, and Gaussian process regression (GPR). Model performance was assessed using RMSE, MAE, MAPE, and R^2 . Among these, GPR and wide neural network achieved the highest predictive accuracy, reproducing the strongly nonlinear FELA trends with R^2 values approaching 0.99. Quadratic response surface models were also developed for discrete values of s_u0 , providing closed-form expressions for N_su . The integrated FELA, machine learning, and response surface framework provided accurate predictive capability and practical formulations for assessing the vertical bearing capacity of skirted mudmat foundations within the investigated parameter range.

This study analyzes seismic hazards in Gujarat’s mainland, emphasizing two major urban cities, Vadodara and Surat, which are classed as seismic zone III under Seismic Code IS:1893-2016. The regions have a typical geological setup, which can sustain large amplified shaking not only from local earthquakes but also from significant events originating in the Kutch and Saurashtra regions. Rapid growth of urban areas, alluvial soil conditions, and proximity to active faults increase seismic risk, particularly during smart city and infrastructural development projects. To determine the potential hazard, appropriate site characterization and determination of the soil properties are essential to design a structure with safety and stability. This establishes the great need for carrying out seismic microzonation of both regions. The study improves site characterization by analyzing geological, geotechnical, and geophysical data such as borehole data, SPT values, and MASW-based shear wave profiles. Probabilistic and deterministic methods assess bedrock-level PGA, indicating increased seismic risk. The PGA models produced higher-than-expected results in several city regions, showing the region’s susceptibility to both near-field and far-field seismic events. Liquefaction potential mapping identifies major city areas near riverbanks as high-risk zones. The findings assist earthquake-resistant infrastructure planning, providing important insights for policymakers and urban resilience.

The utilization of biodegradable substances for the improvement of poor soil has given better outcomes in the field of geotechnical engineering. They diminish the void proportion and thickness of absorbed water in the soil particles and boost the compaction of the subgrade. A decrease in moisture content causes an increase in shrinkage. This will bring about harm to the construction. In the recent years, manufacturers are claiming the increase in soil shear strength, decreasing in liquid limits, and swell index of the soil. Recent studies suggest that adding industry waste products like bottom ash or fly ash into the subgrade soil increases the California bearing ratio (CBR) values of the soil and decreases the swelling potential. In the present study, literature review and laboratory work were carried out on the mechanical stabilization of pavement subgrade mixed with industrial bottom ash (BA). In this study, bottom ash (BA) has been used as a filler material. An attempt has been made to evaluate the properties of soil, such as bearing capacity by replacing it with bottom ash (BA). Environmental scanning electron microscope (ESEM) study conducted to study shape and texture of particles of bottom ash and soil. Different proportions of bottom ash were mixed with locally available (well-graded sand) soil to assess their effect on the engineering properties of soil. Series of tests like California bearing ratio (CBR) of soil were carried out with different dosages of bottom ash with a varying range of 0 to 30

This paper presents the study on the clayey soil reinforced with polyethylene terephthalate (PET) waste. Post-consumer plastic water bottle was used as a PET waste. Plastic bottles were cleaned and strips were cut manually maintaining aspect ratio 2 and 4. The recycled PET strips were mixed in clayey soil in various combinations. This combination ranges from 0 to 1

The present research paper reviews the progressive development of the seismic hazard analysis of the Gujarat region. In peninsular India, Gujarat and its neighboring states witnessed frequent earthquakes that can be categorized as deadly and damaging, although they were located far from any plate boundaries. In India, the zonation map has been modified and updated regularly. Seismic zonation was done at the national and regional levels, considering different approaches. A thorough investigation of the local site characteristics in terms of geological, geophysical, and geotechnical qualities, including microzonation studies, is required to address the issue of seismic hazards. The various methodologies have limitations adopted in the literature to carry out seismic hazard analysis and site-specific studies in Gujarat. The seismic hazard analysis is a very essential procedure to develop a microzonation map of the region. Peak ground acceleration values at the bedrock level can be determined by hazard analysis. This paper is about how different researchers tried to find earthquake risks in different parts of Gujarat using different methods.

Pavement subgrade design relies on the resilient modulus (Mr) r ) to analyze structural response to vehicle-like loading. Adding stabilizers to the soil subgrade makes estimating Mr r difficult and resource-intensive. This study uses an automated machine learning (ML) strategy to predict the Mr r of stabilized clayey soil using recycled plastic waste. The proposed method automates model selection and hyperparameter tuning, making it a feasible alternative to tedious ML modeling and costly laboratory testing. From extensive laboratory investigation involving 3285 experimental data points, the automated ML model using Bayesian optimization evaluates ensembles, support vector machine (SVM), neural network (NET), decision trees, (TREE), and Gaussian process (GP) regression models, identifying the best model based on cross-validation mean squared error (MSE). Bayesian optimization explores hyperparameter spaces to find optimal configurations, enhancing the accuracy, scalability, and reliability of the prediction model. The optimization process yielded the best results for the ensemble least square boost (LSBoost) model with a cross-validation mean squared error (MSE) value of 6.723x10-- 29 . The optimized ML model's performance is measured using R2 2 and adjusted R2. 2 . The LSboost model's R2 2 and adjusted R2 2 values of 0.9999 suggested overfitting, prompting further investigations using performance metrics like root mean squared error (RMSE), mean absolute error (MSE), and probability density function (PDF) for normalized absolute error (NAE) for training and testing datasets for the predictive ML model. The small RMSE and MAE (0.0049 and 0.0005) values and symmetrical NAE distribution of the proposed ML model demonstrate its high accuracy and generalization capabilities. The proposed model was subsequently tested on the new, unseen data and achieved predictions with an error rate of 0.24%. This confirms the proposed ML model's superiority over conventional deformation models, making it ideal for reliable geotechnical engineering applications.

The geological faults, soil amplification, mass, and stiffness of the building governs its seismic performance. The seismic vulnerability of buildings is assessed in this study considering all the above mentioned parameters. The extended finite fault modelling is used to generate ground motions at the engineering bedrock level. Furthermore, the field tests are carried out using multichannel analysis of surface wave (MASW) equipment on soft and medium soil conditions and results are used for the ground response analysis to obtain surface-level ground motions. These motions are used for nonlinear time history analysis of the reinforced concrete buildings with different masonry infill orientations. Finally, the outcome of the analysis is to derive the fragility curves using inter-storey drift (ISD) as damage measure (DM) and peak ground velocity (PGV) as an intensity measure (IM).

As per IRC 37, the design of flexible pavement requires the accurate prediction of resilient modulus for bituminous concrete. This, determination of M_r requires specialized test equipment, which may not be available in many laboratories. Therefore, it would be rather reasonable to create a model that could estimate M_r from easy to estimate volumetric parameters and other parameters obtained from sample conventional tests. This study aims to investigate the effect of different binders (VG30, VG40, PMB and CRMB), binder contents, volumetric parameters (air voids) and temperature on Resilient Modulus ( M_r ) in Bituminous Concrete (BC) course and Dense Bituminous Macadam (DBM) course. The samples were compacted using the Marshall Compacter and subsequently the volumetric parameters were calculated. The Indirect Tensile Strength (ITS) test was conducted to calculate the ITS and Toughness. The Repeated Load Indirect Tension Test was conducted to find out the Resilient modulus ( M_r ) values for all mixes. The regression analysis was performed using the Microsoft Excel tool, and the relationship between resilient modulus, volumetric parameters and ITS was developed. Using the final model, Resilient Modulus of mixtures may be predicted from volumetric parameters and indirect tensile strength under comparable or different testing conditions.

Subsurface geology and geotechnical properties play a significant role for the amplification of ground motion at the time of seismic events. Shear wave velocity model is a necessary input for the site characterization of any region. In this study, geophysical investigations in reference to multichannel analysis of surface wave (MASW) and seismic refraction tests have been carried out at 64 places in Vadodara city. The investigations were performed in the study region by dividing the whole region into 2 × 2 km grid size. SeisImager software is used to determine the shear wave velocities (Vs) and compressional wave velocities (Vp) at various depths. Around 430 borehole data have been synthesized to prepare soil profiles which include the information such as soil type, SPT-N value with depth, and water table. The soil profile of the Vadodara region is alluvium soil with loose sediments. The soil layers observed at different depths mainly consist of silty sand, silty clay, silt of low to high plasticity, clay of low to medium plasticity. Shear wave velocity and compressional wave velocity models have been generated at 5, 10, 15, 20, 25, and 30 m depth through ArcGIS software. The classification of the substrata based on the shear wave velocity profile at 30 m depth (Vs30) has been made by using soil characterization. The obtained output from the study will be used for further studies such as liquefaction assessment, seismic hazard, and risk model of the study region.

The research of seismic hazards along with their preparedness is critical for the development of structures which are both safe and economically effective. Ankleshwar, also known as the "Chemical Capital of India," is located in Bharuch district situated on Gujarat's south-west coast and it is categorised as seismic zone III by the Indian seismic zonation system. Past earthquake data and accessible seismotectonic information were used to conduct a deterministic seismic hazard study of the Bharuch region. After processing earthquake data obtained from 1819 to 2019, a separate seismic catalogue encompassing a 400-kilometer radius around Bharuch city was created. To get rid of the dependent events, the complete catalogue was declustered. Using basic mathematical procedures, the minimum distances from every seismic source generating tectonic activity were estimated. Predictive correlations for the region were used to estimate the Peak Ground Acceleration (PGA) values at bedrock level. The present analysis shows that with a maximum probable earthquake of magnitude 5.8 triggered by the Narmada Son Fault (NSF), the values of PGA of Bharuch region have ranged from 0.086 to 0.51 g. The key design parameters for the Bharuch city and surrounding region are provided by the PGA model discussed in this study.

The earthquake that took place at Bhuj in 2001 acted as a wake-up call that triggered a review of the seismic risk in several areas of the nation. Seismic microzonation analysis benefits greatly from in-depth investigations of both geotechnical and geophysical conditions. This study aims to create correlations between the conventional SPT-N value and the s - wave velocity for different soil conditions in the Dahej port. For the geophysical site characterization, the shear wave velocity models were created using the MASW method and the bundle of software known as SeisImager/SW was used to perform an analysis of the test results. Moreover, the correlations are compared to the relationships established by other scientists. The suggested correlations will be beneficial for the congested areas of the vibrant area, where testing is neither practical nor cost-effective. Such empirical correlations will be used for other similar geological and geophysical site conditions when they have gone through the essential validation stages. To analyze the ground response and a hazard assessment of the study region, the obtained correlations can be used.

The present work studies the effect of adding Electrical Grade Glass (EG) fibers and white Alkali Resistant Glass (ARG) fibers on performance in terms of strength of high-grade Concrete. For this, experiments were carried out to measure compressive, tensile, and flexural strength of a high-grade concrete mix added with EG and ARG fibers at dosages of 0.6%, 0.8%, 1.0% and 1.2% by weight of cement. The compressive, tensile, and flexural strength increases by 16.4%,12.14%, and 7.96% respectively increase in case of EG Fibers and 21.2%,14.48%, and 10.15%, respectively in case of ARG fibers for 1.2% dosage compared to standard mix. The increase in the strength parameters comes at an additional cost of just 3.2% for EG fibers and 2.6% for ARG fibers.

Bhuj 2001 earthquake was alarmed for the seismic hazard assessment of different regions of the country. Detailed geotechnical and geophysical study provide important inputs for the seismic microzonation study. In the present paper, the correlation has been developed between standard penetration test number and shear wave velocity for different categories of soil in Vadodara city. The shear wave velocity models have been obtained through multichannel analysis of surface wave (MASW), which is an effective technique for geophysical site characterization. The field program is set in 2 km × 2 km grid size covering 67 test locations in the entire Vadodara city. The test data are analyzed through the package of SeisImager/SW software. Further, 430 borelog data were collected from various private and government agencies for the investigation of soil properties. Normalized consistency ratio and residual plots have been generated for the validation of the predicted correlations. These correlations are also compared with the relations developed by other researchers. The capability of the proposed correlation is also checked by plotting the map of the scaled relative error versus cumulative frequency. It is found that developed correlations give good prediction performance. The proposed correlations will be the advantageous for the dense locations of the busy city where testing is not feasible and economical. These empirical relations will be further used for similar geotechnical and geological site conditions after proper validation. The proposed correlations can be further used for the ground response analysis and vulnerability assessment of the study region.

Past destructive earthquakes have provided the evidences of influence of local site condition on ground motions. The amplification of ground motion on the surface is strongly affected by the geotechnical characteristics of the region through which the seismic waves travelled. The present study is an attempt to assess the local soil effects in modifying the earthquake ground motion using one-dimensional ground response analysis for the central Gujarat region. The input parameters namely shear wave velocity profile, dynamic soil characteristics and ground motions are required to analyse the ground response at 66 locations of the study region. The results have been presented in terms of various maps, i.e., peak ground acceleration, predominant frequency and spectral acceleration. Based on the site characterisation response, spectra have been developed for the central Gujarat region. The results are also compared with the Indian Standard code. Site response study shows that the large amplification are observed in the ground motion at surface level as compare to rock level acceleration.

Structural characteristics, type of earthquake and geotechnical and geophysical attributes are important parameters while analysing the seismic performance of any structure. Thus, the present study thoroughly estimates the seismic vulnerability, which includes (i) extended finite fault modelling, for generating ground motion at bedrock level, (ii) multichannel analysis of surface wave (MASW) testing on soft soil site and 1-D ground response analysis to simulate amplification caused by soft soil site and (iii) nonlinear analysis of buildings. A four-storey reinforced concrete (RC) building with different arrangements of unreinforced masonry (URM) infill is considered, namely bare frame (BF), open ground storey (OGS), fully infill (FI) frame and partially infill (PI) frame. The finite element models of these frames are developed in opensees to study their nonlinear dynamic behaviour using synthetically generated ground motions. Finally, the fragility curves are generated for all four building frames. The results show that the median peak ground acceleration (PGA) value of the PI frame is almost two times the OGS frame for all damage states. Also, the BF, PI and FI frames designed using standard practices shows the performance level of collapse prevention, whereas the OGS shows a high damage probability of collapse under design-level earthquake.

A network of drainage patterns and associated morphometric analysis are important as it forms various attributes of a watershed. Analysis of these attributes is carried out by spatial analysis which is essential for studying several hydrological response interactions within the watershed catchment area. In the present work, five stream networks of a head watershed Verakhadi were derived from SOI toposheet (scale = 1:50,000), SRTM-GL1, AW3D30, GDEM-V2 and CartoDEM-V3.1. The calculated basin morphometric attributes of drainage network derived from all four 30-m-resolution satellite-based DEMs were compared with SOI toposheet-based drainage network which is essential for estimating the accuracy of watershed hydrological response to a natural event (storm). The capability of all four satellite-based DEMs to represent linear, areal and relief aspect of the drainage basin was evaluated. Morphometric parameter comparison of stream network derived from various DEMs is an indirect way of assessing the relative vertical accuracy of DEM. It is observed that DEMs with same spatial resolution can have variable morphometry derivatives due to different data acquisition and data processing techniques used for DEM generation. The outcome of this study will help to understand the complexity and susceptibility of the various morphometric factors arises while dealing with different data acquisition and processing techniques. The study suggests that SRTM-GL1 performs better in terms of drainage delineation and basin morphometry, followed by AW3D30, CartoDEM-V3.1 and GDEM-V2 when compared with SOI toposheet-derived terrain attributes.

The seismic scenario of the peninsular India has been changed due to many devastating earthquakes in the past few decades. The present paper discusses the hazard analysis with deterministic and probabilistic approaches for Vadodara region. Homogeneous seismic catalogue has been prepared covering the longitude 68 degrees E to 77 degrees E and latitude 18 degrees N to 26 degrees N for the study region and seismotectonic model has been developed for the different moment magnitude range of the earthquake events. Four ground motion prediction relationships have been used to evaluate the peak ground acceleration value at rock level for the Vadodara region.

The Vadodara region falls in seismic zone-III as per IS 1893:2016 and surrounded by highly active seismic sources. Seismicity of the Vadodara region has been determined by the evaluation of peak ground acceleration (PGA) model considering probabilistic framework. Probabilistic analysis has been carried out considering the earthquake data for the time interval between 1668 and 2017. The seismic parameter ‘b’ has been estimated as 0.815 ± 0.001 by adopting suitable recurrence relation. Four ground motion prediction relationships have been adopted to estimate the hazard of the study region. The PGA model at rock level has been quantified by dividing the study region into the grid size of 1 km × 1 km, which varies from 0.054 to 0.071 g and 0.104 to 0.139 g for 10% and 2% probability of occurrence in 50 years, respectively. The results will be further useful for designing earthquake-resistant structures, risk mitigation and future city planning.

Roads and highways are one of the most important assets for the consequential progress of any developing country. Traditional methods of road maintenance have certain lacunas due to which proper road maintenance is not carried out effectively. Improper road maintenance can lead towards a state of expensive rehabilitation and reconstruction, and the concept of managing roads as assets is not served. Proper maintenance and management of these roads is the need of the day. Output and Performance-Based Road Contracts is the innovative method for the maintenance and management of roads ensuring efficient and effective delivery of maintenance service and maintenance of roads as assets. Roads and Building Department, Government of Gujarat, is about to implement its first pilot OPRC project having a road network length of 103 km. This paper describes the effectiveness of Output and Performance-Based Road Contract with prepared service level criteria for the proposed region.