Limited studies dealt with the expansive unsaturated soils in the case of large-scale model close to the field conditions and therefore, there is much more room for improvement. In this study, expansive （bentonite–s...Limited studies dealt with the expansive unsaturated soils in the case of large-scale model close to the field conditions and therefore, there is much more room for improvement. In this study, expansive （bentonite–sand （B–S） mixture） and non-expansive （kaolin） soils were tested in different water contents and dry unit weights chosen from the compaction curve to examine the effect of water content change on soil properties （swelling pressure, expansion indices, shear strength （soil cohesion） and soil suction） for the small soil samples. Large-scale model was also used to show the effect of water content change on different relations （swelling and suction with elapsed time）. The study reveals that the initial soil conditions （water content and dry unit weight） affect the soil cohesion, suction and swelling, where all these parameters slightly decrease with the increase in soil water content especially on the wet side of optimum water content. The settlement of each soil at failure increases with the increase in soil degrees of saturation since the matric suction reduces the soil ability to deform. The settlement observed in B–S mixture is higher than that in kaolin due to the effect of higher swelling observed in B–S mixture and the huge amount of water absorbed which transformed the soil to highly compressible soil. The matric suction seems to decrease with elapsed time from top to bottom of tensiometers due to the effect of water flowing from top of the specimen. The tensiometer reading at first of the saturation process is lower than that at later period of saturation （for soil sample B–S3, the tensiometer #1 took 3 d to drop from 93 kPa to 80 kPa at early stage, while the same tensiometer took 2 d to drop from 60 kPa to 20 kPa）.展开更多
The construction industry is a sector that contributes a lot to the economic growth of Malaysia, as it is developing rapidly similar in fashion to other developing countries around the world. In line with the 9th Mala...The construction industry is a sector that contributes a lot to the economic growth of Malaysia, as it is developing rapidly similar in fashion to other developing countries around the world. In line with the 9th Malaysia Plan, development in Malaysia must meet current and future needs to achieve sustainability in economic development, as well as functioning as a social and environmental responsibility for prosperity without compromising the needs of future generations. To ensure that the government＇s objective is met, construction industry should implement the LCC （life cycle costing） method in structure and infrastructure projects so as to not cause losses to the industry itself and to the government. Through LCC, factors contributing to, and the associated cost of maintenance works for a building are identified at the design stage to obtain a more accurate projection of the total cost. This paper describes the LCC as a vital element in the construction industry since this method can drive quality improvement by taking into account the comprehensive cost of a project. The main aim of this paper is to aid in understanding the application of the LCC concept for the construction industry, particularly for the maintenance phase. This paper also identifies LCC processes involved in a building construction project and subsequently provides recommendation on appropriate measures to implement LCC in the construction industry in Malaysia.展开更多
This paper is an attempt to solve the soil-pile interaction problems using the boundary element method（BEM）.A computer package called PGroupN,which deals mainly with the analysis of the pile group problem,is employe...This paper is an attempt to solve the soil-pile interaction problems using the boundary element method（BEM）.A computer package called PGroupN,which deals mainly with the analysis of the pile group problem,is employed in this study.Parametric studies are carried out to assess the impacts of the pile diameter,pile length,ratio of spacing to diameter and the thickness of soil stratum.The external load is applied incrementally and,at each increment,a check is made that the stress state at the pile-soil interfaces does not violate the yield criteria.This is achieved by specifying the limited stresses of the soil for the axial pile shaft capacity and end-bearing resistance.The elements of the pile-soil interface yielded can take no additional load,and any increase in load is therefore redistributed between the remaining elements until all elements have failed.Thus,by successive application of loading increments,the entire load-displacement relationship for the pile group is determined.It is found that as the applied load reaches the ultimate bearing capacity of the pile group,all the piles will share the same amount of load.An exception to this case is for the center pile in a group of 9 piles embedded in clay,which is not consistent with the behaviors of the other piles in the group even if the load reaches the ultimate state.For the 4 piles group embedded in clay,the maximum load carried by the base does not exceed 8% of the load carried by each pile with different diameters.This low percentage ascertains that the piles embedded in cohesive soils carry most of the load throughout their shafts.展开更多
文摘Limited studies dealt with the expansive unsaturated soils in the case of large-scale model close to the field conditions and therefore, there is much more room for improvement. In this study, expansive （bentonite–sand （B–S） mixture） and non-expansive （kaolin） soils were tested in different water contents and dry unit weights chosen from the compaction curve to examine the effect of water content change on soil properties （swelling pressure, expansion indices, shear strength （soil cohesion） and soil suction） for the small soil samples. Large-scale model was also used to show the effect of water content change on different relations （swelling and suction with elapsed time）. The study reveals that the initial soil conditions （water content and dry unit weight） affect the soil cohesion, suction and swelling, where all these parameters slightly decrease with the increase in soil water content especially on the wet side of optimum water content. The settlement of each soil at failure increases with the increase in soil degrees of saturation since the matric suction reduces the soil ability to deform. The settlement observed in B–S mixture is higher than that in kaolin due to the effect of higher swelling observed in B–S mixture and the huge amount of water absorbed which transformed the soil to highly compressible soil. The matric suction seems to decrease with elapsed time from top to bottom of tensiometers due to the effect of water flowing from top of the specimen. The tensiometer reading at first of the saturation process is lower than that at later period of saturation （for soil sample B–S3, the tensiometer #1 took 3 d to drop from 93 kPa to 80 kPa at early stage, while the same tensiometer took 2 d to drop from 60 kPa to 20 kPa）.
文摘The construction industry is a sector that contributes a lot to the economic growth of Malaysia, as it is developing rapidly similar in fashion to other developing countries around the world. In line with the 9th Malaysia Plan, development in Malaysia must meet current and future needs to achieve sustainability in economic development, as well as functioning as a social and environmental responsibility for prosperity without compromising the needs of future generations. To ensure that the government＇s objective is met, construction industry should implement the LCC （life cycle costing） method in structure and infrastructure projects so as to not cause losses to the industry itself and to the government. Through LCC, factors contributing to, and the associated cost of maintenance works for a building are identified at the design stage to obtain a more accurate projection of the total cost. This paper describes the LCC as a vital element in the construction industry since this method can drive quality improvement by taking into account the comprehensive cost of a project. The main aim of this paper is to aid in understanding the application of the LCC concept for the construction industry, particularly for the maintenance phase. This paper also identifies LCC processes involved in a building construction project and subsequently provides recommendation on appropriate measures to implement LCC in the construction industry in Malaysia.
文摘This paper is an attempt to solve the soil-pile interaction problems using the boundary element method（BEM）.A computer package called PGroupN,which deals mainly with the analysis of the pile group problem,is employed in this study.Parametric studies are carried out to assess the impacts of the pile diameter,pile length,ratio of spacing to diameter and the thickness of soil stratum.The external load is applied incrementally and,at each increment,a check is made that the stress state at the pile-soil interfaces does not violate the yield criteria.This is achieved by specifying the limited stresses of the soil for the axial pile shaft capacity and end-bearing resistance.The elements of the pile-soil interface yielded can take no additional load,and any increase in load is therefore redistributed between the remaining elements until all elements have failed.Thus,by successive application of loading increments,the entire load-displacement relationship for the pile group is determined.It is found that as the applied load reaches the ultimate bearing capacity of the pile group,all the piles will share the same amount of load.An exception to this case is for the center pile in a group of 9 piles embedded in clay,which is not consistent with the behaviors of the other piles in the group even if the load reaches the ultimate state.For the 4 piles group embedded in clay,the maximum load carried by the base does not exceed 8% of the load carried by each pile with different diameters.This low percentage ascertains that the piles embedded in cohesive soils carry most of the load throughout their shafts.
