Papers by Dr. S.N. Malkanthi
Journal of the university of Ruhuna, Nov 30, 2023
The construction industry is a competitive, complicated environment where people with various ski... more The construction industry is a competitive, complicated environment where people with various skills, perspectives, and levels of knowledge. Conflicts are unavoidable in this complicated setting due to differences in perspectives among project participants. Conflicts quickly develop into disagreements if they are not handled properly. The end goals of every construction project are to reduce cost, improve quality, and complete the job on schedule. One of the biggest things that prevents the construction project from being successfully finished is disputes. Construction conflicts have become significantly more common and complex in recent years. Consequently, it's critical to understand what leads to disagreements. However, in the event of a dispute, Dispute Resolution Methods are implemented to resolve differences and prevent the breach of relationship and communication between the parties to achieve the construction project in the desired time, budget, and quality. The purpose of this study was to identify and evaluate the main factors that contribute to building disputes. Through a comprehensive literature review, 39 root causes of construction disputes were identified under seven categories namely client-related, contractor-related, designrelated, contract-related, human behavior-related, project-related, and external factors. The responses gathered from construction industry specialists in Sri Lanka via a questionnaire survey were used to determine the significance of those indicated factors by converting them to the Relative Importance Index(RII). Results showed that the project-related category is the most significant category that causes disputes in construction projects. Additionally, correlation analysis shows that there is a strong relationship among the dispute-causing categories. Also, the respondents are familiar with "arbitration" as the dispute resolution method and they are satisfied with the "conditions of contract" as a Regulatory framework for dispute resolution. The findings support the notion that construction disputes are a source of concern for every project and that the best way to address this issue is to prevent and cautiously manage them to ensure the smooth operation of the construction process.
Engineer: Journal of the Institution of Engineers, Sri Lanka, 2023
The inherent nature of construction projects is long duration and high cost. Extended
project d... more The inherent nature of construction projects is long duration and high cost. Extended
project duration leads to escalation of cost. If the project duration is too long, the initial estimation may not be sufficient to recover the actual cost of the contract. To address this problem, Construction Industry Development Authority (CIDA) has introduced a price adjustment method called the “ICTAD formula method for adjustments to contract price due to fluctuation in prices”. Contract documents related to construction projects also provide some provisions to address the issues with material price fluctuations. This study investigated the practices of contractors to minimize the effect of price variation and support of price fluctuation clauses to minimize the impact of price variation. A questionnaire survey was conducted among the professionals to represent CS2 to C5 grade construction companies registered at CIDA. The questionnaire consisted of practices of contractors to minimize the effect of price variation and the impact of using price fluctuation clauses in different aspects. Collected responses were converted to a quantitative value using the relative importance index (RII). In addition, SPSS software was used for the critical review of responses. The results revealed that contractors mostly agree with using price fluctuation clauses to recover the increased project cost due to increased construction input prices. Further, results are evident that using price fluctuation clauses helps to fair risk sharing between the contractor and the client.
Case Studies in Construction Materials, 2021
Abstract Earthen materials have been used in civil engineering construction worldwide with differ... more Abstract Earthen materials have been used in civil engineering construction worldwide with different forms, such as mud, adobe, rammed earth and bricks. Compressed stabilized earth blocks (CSEB) can be considered as a new member of the earthen building material family. Also, it can overcome the problems associated with fired bricks and cement blocks. Cement is the most commonly used as stabilizers to enhance the properties of CSEB. The governing factor which controls the properties of CSEB is the amount of clay content in the soil. Researches have concluded that about 25% of clay and silt (finer) content contributes to high compressive strength. However, controlling of larger particles is not addressed much. This study focused on controlling the finer content as well as larger particles with the use of construction waste (mostly with crushed concrete) and river sand. Selected soil was modified to get the finer content as 5%, 10%, 15% and 20%. This modification was done by adding river sand and construction waste to the soil to optimize the particle packing based on particle packing theories. Cement was used as the stabilizer with 6%, 8%, and 10%. (150x150x150) mm3 cubes were cast and tested for dry density, water absorption, 28 days wet and dry compressive strength, accelerated erosion and compared with SLS 1382; part 2 requirements. Block properties were conformed with SLS 1382 requirement when finer contents are 10% and 5% with 10% and 8% cement. Further, Industrial-scale blocks of (350×100×175) mm3 made with 10% finer and 8% cement satisfied the Grade 1 block properties. CSEB made mixing with construction waste contributes to manage the environmental pollution due to construction waste while giving a fair solution to the problem with the shortage of building materials.
Engineering, Technology & Applied Science Research
The use of earth as a building material, in different forms, such as unburnt and burnt bricks, ra... more The use of earth as a building material, in different forms, such as unburnt and burnt bricks, rammed earth, mud blocks, and soil blocks, is a common practice globally. This study is focused on soil blocks stabilized with cement which are referred to as Cement Stabilized Earth Blocks (CSEBs). The strength and durability of CSEBs are primarily governed by the amount of silt and clay content (finer) in the soil. Many researchers have shown that low finer content improves the properties of CSEB and they have altered the finer content by adding different additives. The current study used a washing method to reduce the finer content and fly ash was utilized as finer to re-fill the soil to the required finer content amount. Also, soil grading was modified by adding larger particles that were separated from the same soil to fit the soil grading to the optimization curves mentioned in the literature. The finer content was changed to 5%, 7.5%, and 10%. Blocks were made by stabilizing the soi...
country. Iit is obvious that the price of one material is not same in different districts. Theref... more country. Iit is obvious that the price of one material is not same in different districts. Therefore aim of this study is to evaluate the suitability of using unique price indices for the price fluctuation adjustment based on the ICTAD formula method. To achieve this aim the research aimed to find the relationship between ICTAD price adjustments & true price adjustments through the data analysis and to propose a modification to increase the accuracy of ICTAD formula. To fulfil above objectives, prices of sand, aggregate, rubble and bricks were collected from January, 2015 to August, 2016. First the behaviors of material prices of Colombo district were analyzed. Results show that the indices variation and variation of price of selected materials in Colombo are having similar tendency. Then those data were converted to a form of indices considering Colombo material price as the base. Results shows there is a gap between price variation in Colombo and other districts. Among the selecte...
Time and cost overruns are common in construction projects in Sri Lanka. This paper presents the ... more Time and cost overruns are common in construction projects in Sri Lanka. This paper presents the results of a questionnaire survey conducted to identify and evaluate the relative importance of significant factors causing time and cost overrun in construction projects. The survey covered previously identified factors which were grouped into twelve major categories in cost overruns and twenty one factors for time overruns. Respondents of this survey included personnel from Clients, Consultants, Contractors involved in construction projects. The results of the study revealed the main causes of time and cost overruns in the construction projects and mitigating measures were identified according to the causes and classified as Preventive, Predictive, Corrective and Organizational measures. Therefore effective project planning, controlling and monitoring should be established to enhance project performance in order to minimize or avoid time and cost overruns in construction projects.
Case Studies in Construction Materials, 2020
Compressed stabilized earth blocks (CSEBs) are comparatively new earth-based materials similar to... more Compressed stabilized earth blocks (CSEBs) are comparatively new earth-based materials similar to rammed earth, adobe, and bricks. Additionally, CSEBs can overcome the problems of fired bricks. The most common stabilizers used for CSEB production are cement and lime. Lime is environmentally friendlier than cement. This study was performed with the aim of finding the suitability of lime and lime-cement combinations as the stabilizer for CSEB production with reduced clay and silt contents. The soil selected for this study was modified to obtain clay and silt contents of 5 %, 10 %, and 15 %. River sand was used to change the clay and silt contents of the soil. Lime percentages of 5 %, 10 %, and 15 % by weight as the stabilizer were selected. The stabilized blocks were tested for dry density, water absorption, and 28-day wet and dry compressive strengths and were compared with the SLS 1382 standards. Cement-stabilized blocks with 10 % and 8 % cement by weight were prepared for compariso...
Bolgoda Plains
Soil has been used as a building material in different forms, such as mud, adobe, rammed earth, a... more Soil has been used as a building material in different forms, such as mud, adobe, rammed earth, and bricks. Compressed Stabilized Earth Block (CSEB), a form of soil blocks with different additives including cement, fly ash, and lime, is a sustainable building material with many advantages compared to other conventional building materials. The usual practice of past researchers in producing CSEB was to add different materials like sand to the soil to control its clay and silt (finer) content. A high level of finer content is not desirable when it comes to the strength and durability of CSEB. This study proposes to reduce/ extract the finer content in the soil by washing it using a conventional concrete mixing machine.
Engineering, Technology & Applied Science Research
Soil as a building material has been used in different forms such as mud, adobe, rammed earth and... more Soil as a building material has been used in different forms such as mud, adobe, rammed earth and bricks. The present study focuses on producing Compressed Stabilized Earth Blocks (CSEBs) giving attention to the particle size distribution in the soil mixture. The literature established that compressive strength significantly depends on clay and silt content and 25% of clay and silt produce optimum results while no attention has been given to the amount of other, larger particles. Soil grading refers to the combination of different-size particles in a soil mixture. The correct selection of sizes in the correct proportion may cause improvements in CSEB properties. This paper explains the application of particle packing technology for the improvement of CSEB properties. The theoretical concepts provide a continuous particle size distribution, and the soil used for the experiments also has a continuous particle size distribution. The soil used in the experiments was subjected to washing...
Engineer: Journal of the Institution of Engineers, Sri Lanka
Construction industry plays an important role in the development of a country. The success of any... more Construction industry plays an important role in the development of a country. The success of any project will depends on how that project can achieve its objectives in terms of cost, quality and duration. In order to achieve success in a project, it would be essential to plan that project well and have a proper monitoring mechanism in place. Cost overrun is a major problem encountered by many contractors as it makes the profit of a project less secure for the contractor in addition to causing many other problems to all the parties involved. Good cost control techniques would be essential to solve those problems. Thus, it is important to identify cost controlling techniques and their impact on cost overruns. This study was done using a questionnaire survey conducted among C1-C5 grade contractors. The data collected were analysed by converting them into quantitative values using percentage analysis and weighted score analysis. The results indicate the cost controlling practices that are in frequent use and their importance in minimizing the cost overruns in order to reduce over budget and overheads while securing anticipated profits. Finally, it is suggested that CIDA (ICTAD) should encourage contractors to use cost controlling techniques, by conducting training programs, awareness programs, etc. It is also suggested to make the use of some of ICTAD documents mandatory.
IOP Conference Series: Materials Science and Engineering
Compressed Stabilized Earth Blocks (CSEB) has been using as a walling material since few decades.... more Compressed Stabilized Earth Blocks (CSEB) has been using as a walling material since few decades. It is an environmentally friendly material but not economical in commercial application. Durability of CSEB is still under research and acceptance of CSEB by people also is a main challenge. Main ingredient that acts both positively and negatively on properties of CSEB is the presence of clay & silt. Many researches have been carried out on CSEB altering the clay content by adding sand, fly ash or similar materials. This study was carried out with the objective of establishing the feasibility of lowering clay & silt content by washing thus achieving requirements. The past research work established the optimum clay & silt in the region of 5 to 20% related to compressive strength but no firm indication of the range associated with the durability of CSEB. The test results based on a pilot study proved dry density is high with lower clay & silt below 15%. Water absorption test recorded that the water absorption is minimum between 10 to 15% of clay & silt content. The compressive strength did not show a significant drop or increase in the clay & silt range of 5% to 20%. These results conclude that the best range for clay & silt as 5% to 20% and can be best achieved by washing soils rather than mixing with sand, fly ash or any other similar material.
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Papers by Dr. S.N. Malkanthi
project duration leads to escalation of cost. If the project duration is too long, the initial estimation may not be sufficient to recover the actual cost of the contract. To address this problem, Construction Industry Development Authority (CIDA) has introduced a price adjustment method called the “ICTAD formula method for adjustments to contract price due to fluctuation in prices”. Contract documents related to construction projects also provide some provisions to address the issues with material price fluctuations. This study investigated the practices of contractors to minimize the effect of price variation and support of price fluctuation clauses to minimize the impact of price variation. A questionnaire survey was conducted among the professionals to represent CS2 to C5 grade construction companies registered at CIDA. The questionnaire consisted of practices of contractors to minimize the effect of price variation and the impact of using price fluctuation clauses in different aspects. Collected responses were converted to a quantitative value using the relative importance index (RII). In addition, SPSS software was used for the critical review of responses. The results revealed that contractors mostly agree with using price fluctuation clauses to recover the increased project cost due to increased construction input prices. Further, results are evident that using price fluctuation clauses helps to fair risk sharing between the contractor and the client.
project duration leads to escalation of cost. If the project duration is too long, the initial estimation may not be sufficient to recover the actual cost of the contract. To address this problem, Construction Industry Development Authority (CIDA) has introduced a price adjustment method called the “ICTAD formula method for adjustments to contract price due to fluctuation in prices”. Contract documents related to construction projects also provide some provisions to address the issues with material price fluctuations. This study investigated the practices of contractors to minimize the effect of price variation and support of price fluctuation clauses to minimize the impact of price variation. A questionnaire survey was conducted among the professionals to represent CS2 to C5 grade construction companies registered at CIDA. The questionnaire consisted of practices of contractors to minimize the effect of price variation and the impact of using price fluctuation clauses in different aspects. Collected responses were converted to a quantitative value using the relative importance index (RII). In addition, SPSS software was used for the critical review of responses. The results revealed that contractors mostly agree with using price fluctuation clauses to recover the increased project cost due to increased construction input prices. Further, results are evident that using price fluctuation clauses helps to fair risk sharing between the contractor and the client.