The paper focuses on the improvement of the clayey soil (A-6) with the locally available and cheap modifiers, in terms of stiffness behavior of the weak subgrade soil for flexible pavement. The modifiers used include lime (hydrated), marble waste and sand. The soil specimens underwent triaxial testing and Clegg impact testing. Triaxial testing involved the assessment of the resilient modulus (M_R) and impact testing using the Clegg Impact Hammer. According to the study, lime proved to be the most influencing modifier as it improves the stiffness of the weak soil better than other modifiers. A quite accurate statistical relationship between the M_R and the variables (including Clegg Impact) involved in the testing procedure has been established

This study presents a cost-based optimization model for the design of isolated foundations in cohesive soils. The optimization algorithm not only incorporates safety requirements in the form of ultimate limit state (ULS) and serviceability limit state (SLS) criteria but also deals with the economics simultaneously. In that regard, the generalized reduced gradient (GRG) method is used for the optimization purpose to achieve the least construction cost of an isolated foundation along with the integration of design parameters as optimization variables. The optimization technique is elaborated using a design example in silty clayey soil and the results of the optimized design are compared with those of the conventional design. The optimization model shows that the optimized design can reduce the construction cost by up to 44% as compared to the conventional design cost for the particular example. Moreover, a sensitivity analysis is also performed to evaluate the quantitative impact of cohesive soil properties, design load, and groundwater table on the construction cost. The results indicate that the construction cost majorly depends on the combined effect of four key parameters: Young’s modulus, recompression index, design load, and groundwater table.

Rice husk disposal has become a great challenge for Pakistan being one of the largest rice producer across the globe. Rice Husk Ash (RHA) contains sufficient pozzolanic properties which opens up opportunities for its usage as cementitious material as partial replacement of Ordinary Portland Cement (OPC). In this research RHA was added as cement replacement in different percentages by weight of cement i.e. 0%, 6%, 12%, 18% and 24% at constant mix ratio of 1:2:4 and water-cement ratio of 0.6 that is M15 grade concrete with a target strength of 15-20 MPa. The properties of concrete like workability, compressive strength, tensile strength, flexure strength, and water permeability were investigated by casting standard concrete samples in the form of cubes, cylinders and beams in addition to cost comparison study The outcomes show that workability of fresh concrete increases with an increase in RHA content and almost all concrete properties studied in this research gave more favorable results at 6% replacement level compared with the control mix.

Footing shapes and ground water table (GWT) greatly affect the bearing capacity and settlement ofcohesive soil. A series of laboratory experiments and simulation techniques are performed to investigatethe effect of footing shapes and GWT on bearing capacity and settlement in cohesive soils. Resultsshowed that by increasing the depth of footing, bearing capacity of cohesive soil increases whilesettlement and stress influence zone decreases. In case of square footing when depth of footing isincreased from 1m to 2.2m bearing capacity also increased from 26.45kPa to 27.90kPa; while settlementand stress influence zone decreased from 0.30mm to 0.20mm and 1.2m to 0.60m, respectively. In case ofrectangular footing when depth of footing is increased from 1m to 2.2m bearing capacity increased from26.25kPa to 27.60kPa; while settlement and stress influence zone decreased from 0.60mm to 0.49mmand 1.53m to 1.15m, respectively. On the basis of high stress influence zone, critical footings are furtherselected to study the effect of GWT. It is observed that GWT does not affect the bearing capacity whenits level is below the footing bottom, while settlement keeps on decreasing with the depth. A Soil StructureInteraction (SSI) model is proposed by comparing different built-in Finite Element Method (FEM) basedmodels in Geo-5 software. Among the studied SSI models, Modified Elastic Model and Modified MohrCoulomb Model proved to be more realistic models in terms of settlement, shear stress and effectivestress

The urban area of Lahore is facing serious problem for the management of storm water due to heavy rainfalls especially in the summer (monsoon) season. The accumulation of storm water is due to the high level of water in the adjacent housing colonies during or after heavy rainfall events. The ongoing and newly proposed construction projects inside the city are supposed to take an unknown period of time for completion and have become an additional reason for water stagnation. Due to the improper or inadequate drainage facilities, the storm water gets stagnant and creates hurdles for the normal on-going activities all over the city. The existing conditions for the drainage facilities are unable to cope up with the aftermaths of heavy rainfalls. In addition, the present storm water drains are becoming insufficient due to rapid developments and need serious attention. This research takes into consideration the current situation of storm water drains in a university campus and proposes sustainable solutions for storm water management and conservation of rainwater. Using the rainfall intensity, suitable runoff coefficient was estimated and by computing, the area based on survey the rational equation was then used to estimate the runoff and design discharges for different return period rainfall events. From point of view of draining facility for managing the storm water as consequences of rainfall events two types of systems were proposed i.e., closed conduit (underground pipe) system based on commercial pipe sizes available in market and open channel system with drains with 30 cm bottom width.