One of the most important problems in the construction industry is variations. They occur in every construction project and the magnitude of these variations varies considerably from project to project. Hence, the variations orders bear great importance right from the inception to completion in the construction industry. Most of the road construction projects in Sri Lanka have experienced a large number of variation orders. The client had to spend more than what was initially estimated in most cases. Sometimes, disputes and unnecessary delays occur due to variations. This study attempted to reveal the possible causes of variation orders in the road construction projects in Sri Lanka. The data were collected through a literature review, a case study analysis focused on 11 road construction projects, and a questionnaire administered to professionals in the road construction industry in Sri Lanka. The study found out that the causes in the local context differ from those in the international context. According to the questionnaire survey, poor estimation was the most significant cause of variation orders. Unforeseen site conditions, political pressure during construction stage, poor investigation, and client-initiated variations occupy the 2nd to 5th places, respectively, in the ranking. This ranking was further proven through the case study analysis.

This investigation is apropos the thermal analysis and structural cooling of brick, cement block and mud concrete block walling materials to compare the thermal comfort of different walling materials. Structural cooling is a method of cooling hot temperature by using the structure. Void spaces in a building block can be studied as porosity. It can be measured by assessing solid to void spaces. The thermal performance can be measured by calculating the time lag and the decrement factor. The initial testing was done in order to understand the thermal conductivity and heat capacity in both wet and dry conditions. The real-world analysis and simulation analysis were used to validate the argument. For the case studies, real-world buildings with an identical plan form but constructed with three different walling materials were used and their thermal performances were measured. And then one building was simulated in order to create an identical scenario. With the real-world observation, it was found that brick walling materials have better time lag and decrement factor with the thickness of 225 mm. An overall analysis shows that mud concrete block has better structural cooling ability and the thermal performance than other wall materials.

This study was carried out to determine the characterization of brown coir fiber which is used as a potential reinforcement in polymer composites. The fiber is extracted from the husk of the coconut seeds which are collected in Sri Lanka. Anyhow the above-mentioned characterization can hardly be...

The energy consumption of affordable housing industry plays a vital role in the environmental sustainability, waste generation and energy consumption. The development of sustainable housing construction methodology helps its country’s economic development and sustainable development. Wall and roof are the most significant building component in a dwelling unit. The walling materials can determine the cost of the building as well as the total life cycle cost of a dwelling unit. In this study, the total life cycle cost of a basic dwelling unit in Sri Lanka, made of mostly available walling materials such as Brick, Hollow cement block, and Cabook, the Mud concrete blocks were calculated by using energy accounting hierarchical structure. The life cycle cost incurred due to change in above-mentioned walling materials were calculated and measured. Additionally, total LCC compared and analyzed. The results show that mud concrete block is the most suitable walling material. The brick has the highest account for the embedded energy. The hollow cement block is the worse building materials in tropics and its carbon footprint is comparatively higher. Even though the brick has higher embedded energy and construction cost, in a long run brick is less expensive than hollow cement block and Cabook walling material. Concluding, mud concrete block is comparatively most sustainable walling material for building affordable housing in tropics.