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Climate change is increasingly exacerbating water shortages worldwide. Among the various repercussions of water scarcity, notably in developing countries, the most critical are the decline in social sustainability and the widening inequality within farming communities. In response, irrigation reforms aimed at establishing farmer-managed networks have been introduced to foster equitable water distribution and enhance the livelihood and food security of underprivileged farmers. However, these reforms have largely fallen short of achieving their social sustainability goals. A significant factor in this shortfall is the farmers' limited capacity and reluctance to assume roles typically filled by bureaucracy under institutional reforms. This study explores farmers' willingness to engage in a World Bank-assisted participatory irrigation infrastructure program. We utilized questionnaire surveys and hierarchical analysis to evaluate how various factors influence farmers' willingness to participate. The findings indicate a multifaceted challenge that intensifies in communities fragmented by socioeconomic and political divides. Particularly, the predominance of large landowners in agricultural communities and the absence of sufficient bureaucratic support for participation are key impediments. Our research offers comprehensive insights into the regional sociopolitical obstacles obstructing farmer involvement in government-led participatory projects. It also guides policymakers in grasping the intricate interplay between program design, execution, and contextual elements, which is crucial for the sustainable development of resource-stressed areas. [ABSTRACT FROM AUTHOR]

In 1839 British East India Company captured the town of Karachi. After an effortless resistance from the locals the fort was conquered by the British commander sir Charles Napier. The village of Kolachi then was annexed to British India and the city was labeled as Karachi. With the British occupation a phase of new sophisticated architecture and development started. Before that the city was based upon the vernacular mud architecture. These developments resulted in an influx of economic migrants who helped in making Karachi as a multinational and a multicultural city. This paper investigates the architectural attributes that the historic core of the city offers. It also discusses the side by side development of the native and British towns. The paper also researches about the existing state of the architecture precedent of the British colonial past of the city and the urban blight occurred to them over time in various forms like vandalism, encroachments, illegal repairs, etc. [ABSTRACT FROM AUTHOR]

This study analyzes the response of various hydrological parameters and future water availability against anticipated climate variations in snow dominated alpine catchment in Austria. The parameters assessed are base flow, environmental flow, total flow, evapotranspiration, and snow cover duration. The distributed hydrological modeling system PREVAH is developed to assess the impacts through the combination of various climate change scenarios produced under the framework of the European project PRUDENCE. The model results clearly indicate an apparent shift from observed trends in monthly, seasonal and annual values. The mean annual changes observed by all model scenarios range between 45% to 60% decrease in snow cover duration, 15% to 20% increase in evapotranspiration, 5% to 15% decrease in base flow, and 15% to 25% decrease in total runoff values. However, mean annual changes observed in available water are marginal, just ranging from -3% to +2%. All regional model projections show more or less the same identical pattern of changes in analyzed parameters. [ABSTRACT FROM AUTHOR]

Tunnels are often preferred for underground transportation in densely populated areas. In these areas, it is almost inevitable for tunnels to run close to some existing pile foundations. Since tunnelling activities induce stress relief and soil movement in the ground, existing piles may suffer from additional axial and lateral forces, bending moments, settlements and lateral deflections. Most of the previous researches on the responses of pile foundations due to tunnel construction were carried out under the plane strain condition. In this paper, a three-dimensional, elasto-plastic and coupled-consolidation finite element parametric study has been carried out to investigate the effects of a 6 m open-face advancing tunnel on a two by two pile group in saturated stiff clay. The influence of different cover-to-diameter (C/D) tunnel ratios (namely 2.0, 2.5 & 3.0) was studied. The objectives of this study are to determine the changes in axial load distribution, changes in shaft resistance along the shaft of pile group and settlement of pile cap due to an advancing open-face tunnel. [ABSTRACT FROM AUTHOR]

Drinking water quantity and quality is of the utmost importance. If the drinking water gets contaminated, it can result in severe health problems. For example, the continuous consumption of drinking water co ntaining more than permissible amounts of fluoride can lead to bone deterioration and increased risk of bone fracture [1]. The present study was carried out to check the quality of underground water of Sukkur city. The analyzed parameters were fluoride, sodium, magnesium, calcium, potassium, iron, arsenic, TDS, pH, conductivity, odor, color and taste. World Health Organization (WHO) standards were followed in present study. Underground water samples were collected from 20 different populated locations of Sukkur city. Only arsenic, pH, iron and potassium were found to be within health safe limits while the rest of the parameters exceeded the permissible standards set out by WHO. The TDS, sodium, fluoride and magnesium were over the limits at some locations. [ABSTRACT FROM AUTHOR]

Development of underground transportation systems consists of tunnels, basement construction excavations and cut and cover tunnels which may encounter existing pile groups during their construction. Since many previous studies mainly focus on the effects of excavations on single piles, settlement and load transfer mechanism of a pile group subjected to excavation-induced stress release are not well investigated and understood. To address these two issues, three-dimensional coupled-consolidation numerical analysis is conducted by using a hypoplastic model which takes small-strain stiffness into account. A non-linear pile group settlement was induced. This may be attributed to reduction of shaft resistance due to excavation induced stress release, the pile had to settle substantially to further mobilise end-bearing. Compared to the Sp of the pile group, induced settlement of the single pile is larger with similar settlement characteristics. Due to the additional settlement of the pile group, factor of safety for the pile group can be regarded as decreasing from 3.0 to 1.4, based on a displacement-based failure load criterion. Owing to non-uniform stress release, pile group tilted towards the excavation with value of 0.14%. Due to excavation-induced stress release and dragload, head load of rear piles was reduced and transferred to rear piles. This load transfer can increase the axial force in front piles by 94%. [ABSTRACT FROM AUTHOR]

In densely built areas, development of underground transportation system often involves excavations for basement construction and cut-and-cover tunnels which are sometimes inevitable to be constructed adjacent to existing piled foundations. In order to gain new insights into single pile responses (i.e. settlement and load transfer mechanism) to an adjacent excavation in saturated silty clay, a three-dimensional coupled- consolidation numerical analysis is conducted in this study. An advanced hypoplasticity (clay) constitutive model with small-strain stiffness was adopted. A linear increase in pile settlement was observed due to excavation-induced stress release. This is because part of the pile is placed within the boundaries of a major influence zone due to excavation-induced ground movement. Based on a settlement criterion, apparent loss of pile's capacity is 14%. A maximum bending moment of about 350 kNm is induced in the pile with the maximum deflection of 28 mm. In addition, mobilisation of shear strength at the pile-soil interface was found to be a key factor governing pile-soil-excavation interaction. During excavation, a downward load-transfer mechanism in the piles can be identified. [ABSTRACT FROM AUTHOR]

In densely built urban areas, it is inevitable that tunnels will be constructed near existing pile groups. The bearing capacity of a pile group depends on shear stress along the soil-pile interface and normal stress underneath the pile toe while the two would be adversely affected by the unloading process of tunneling. Although extensive studies have been conducted to investigate the effects of tunnel construction on existing single piles, the influence of twin tunnel advancement on an existing pile group is merely reported in the literature. In this study, a series of three-dimensional centrifuge tests were carried out to investigate the response of an existing pile group under working load subjected to twin tunneling at various locations in dry Toyoura sand. In each twin tunneling test, the first tunnel is constructed near the mid-depth of the pile shaft, while the second tunnel is subsequently constructed either next to, below or right underneath the pile toe (Tests G_ST, G_SB and G_SU, respectively). Among the three tests, the 2nd tunnel excavated near the pile toe (Test G_ST) results in the smallest settlement but the largest transverse tilting (0.2%) of pile group. Significant bending moment was induced at the pile head (1.4 times of its bending moment capacity) due to the 2nd tunnel T. On the contrary, tunneling right underneath the toe of pile (i.e., Test G_SU) results in the smallest tilting but largest settlement of the pile group (4.6% of pile diameter) and incremental mobilisation of shaft resistance (13%). Due to stress release by the twin tunneling, the axial force taken by the front piles close to tunnels was reduced and partially transferred to the rear piles. This load transfer can increase the axial force in rear piles by 24%. [ABSTRACT FROM AUTHOR]

Innovative public-private partnerships (PPPs) have created potential opportunities for both public and private sector organizations in developing and managing public transportation networks. Through PPPs, public sector agencies are able to overcome budgetary and technical constraints and private sector companies can obtain long-term and sustained business prospects. However, previous studies have noted that despite possessing experience and skills, private sector companies are prone to making serious mistakes that could lead to the failure of a PPP project. Based on extensive case studies, this paper proposes a failure mechanism model that reflects the trails of mistakes made by private sector partners in transportation PPPs. A questionnaire survey was conducted to validate and assess the criticality of the failure drivers in the failure mechanism model and the causal relationships involved. Multiple regression path analysis was then applied to assess the statistical significance and calculate the path coefficients of the causal relationships depicted by the proposed failure mechanism model. This analysis then yielded the path coefficients, which indicate the causal strength of the proposed failure mechanism model along with its statistical significance. Based on the results of multiple regression path analysis, the failure mechanism model was respecified to reflect the validated and statistical significant causal relationships. [ABSTRACT FROM AUTHOR]

This paper gives an insight of how to improve the bond strength of cement in which concrete is replaced with rice husk ash. A concrete mix was prepared and was used in different types of mixes i.e. Control Mix, 10% cement substituted concrete with rice husk ash and polymer modified concrete by incorporation different dosages of polymer in the 10% cement substituted concrete. A bar of 12mm diameter, 300mm in length was placed in the center of the cylindrical specimens for pull out test. It was observed that the bond strength between concrete and steel decreases with the replacement of cement with ash, conversely the bond strength improves with the addition of polymer dosages. [ABSTRACT FROM AUTHOR]