This issue consists of five papers. The first paper, �A Study on Response of Industrial Structure Under Dynamic Loads�, by Swati B Bekkeri and Varsha Gokak, studies the behavior of industrial structure when subjected to dynamic loads. An attempt has been made to study the response with different strengthening mechanisms and to search for an efficient one. Industrial structures may house different types of machines to generate dynamic loads, and the effects of such machines are investigated based on their response. A four-storied special moment resisting frame steel building has been designed using IS: 800 (2007) and working stress design philosophy. The building has composite steel deck system flooring. The system is analyzed using STAAD Pro v8i. The results indicated that responses such as base shear and axial forces increase with use of strengthening systems, and fundamental time period reduces. By providing strengthening systems, the overall structural stiffness increases, thus reducing its fundamental period. Similarly, joint displacement will also be reduced. In the designed structure, it was found that the natural period of the structure is at least 20% away from the operating frequency of the machine placed in the building and thus resonance is avoided and hence large deflection is eliminated. The authors have used different mechanisms for strengthening and found that provision of secondary beams normal to primary beams is most suitable as the strengthening measure in terms of strength and economy. This may not hold true in the case of other industrial buildings.

The second paper, �An Experimental Study on Notched Beam�, by Jyoti I Maled and Kiran M Malipatil, investigates the behavior of beams with notch. A beam with notch will behave more differently than a beam without notch under loading. In a notched beam, propagation of cracks generally starts at the place of notch. Many civil engineering structures use notched beam. How much load a notched beam can bear at the start of the first crack is important in such study. In this study, normal concrete beam without any notch, beam with a central notch and also a normal beam with notch provided after 28 days of curing have been cast as test specimen. The test pieces have been designed using IS: 456 (2000) code and concrete mixed manually. For the tests, two-point loading has been used. It is found that a normal beam can carry 19% more load than the beam which has been post-notched and 14% more than a pre-notched beam. The load carrying capacity of the pre-notched beam is 5% more than the post-notched beam. The deformation of post-notched beam is less than pre-notched beam.

The third paper, �An Experimental Investigation on Concrete Using Different Types of Fine Aggregate�, by G Srinivasan, J Saravanan and G Rajasri, studies the effect of the use of different fine aggregates on concrete. Generally, normal river sand satisfying all requirements of properties as recommended by the code is used in making of concrete. But recently, several investigators have chosen to replace part of the sand with various alternative materials. The authors have tried to find a suitable alternative to river sand. The M-sand has been prepared by crushing hard granite and sea sand collected from nearby source. The concrete mix of grade M25 was designed using IS: 10262 (2009) and the slump value obtained was 65, 68 and 55 for river sand, M-sand and seashore sand, respectively. The results indicated that there is a slight increase in the compressive strength of concrete with full replacement of sand with M-sand or seashore sand. The average value of modulus of elasticity (E) is higher for M-sand than for conventional sand. Average E value decreases with use of seashore sand. Use of seashore sand exhibits a higher value of flexural strength than conventional sand. Rapid chloride penetration test indicated a moderate value for all sands. The authors recommend M-sand and seashore sand as alternative materials to fully replace the conventional river sand. And it was seen from the test results that not all test parameters are superior to the use of conventional river sand. More test studies are needed to suggest a full replacement.

The fourth paper, �An Optimum Mix Proportioning of Eco-Friendly Concrete Using Taguchi�s Approach�, by Syed Mueen, Mohd Umar and A K Kaliluthin, develops an optimum mix design of concrete using Taguchi�s method. Eco-friendly concrete uses waste material as one of its components in making concrete. The production process is eco-friendly and does not cause any environmental damage. In this study, the test materials used are normal cement, sand and aggregate. Further, to replace part of fine and coarse aggregate, fly ash and coconut shell have been used. Coconut shell and fly ash are both waste materials. Before its use, its properties were determined. IS: 10262 (2009) is used to proportion the concrete mix. Taguchi�s method was used to develop optimum mix proportions. From the test results, it is found that concrete mix prepared with use of 10% coconut shell and 0% replacement of fly ash showed better results than any other mix proportions.

The last paper, �The Influence of Steel Fiber on the Mechanical Properties of Concrete: An Experimental and Analytical Study�, by Ilango Sivakumar and Sivagamasundari R, investigates analytically and experimentally the effect of addition of steel fiber on concrete. M40 and M50 concrete have been prepared with addition of steel fibers and tested. Two types of steel fibers, one hooked end and other crimped end, with 0.5% and 1% by volume of concrete have been used in the concrete mix. To increase the workability of concrete, superplasticizer has been added. In order to validate the experimental results, artificial neural network technique has been used. The test results showed that compressive strength, flexural strength and elastic modulus values are on higher side for 1% fiber as compared to 0% and 0.5% fiber use. The compressive strength and also flexural strength increase for M40 and M50 concrete with addition of hooked end or crimped end fibers as compared to conventional concrete. There is an increase in the modulus of elasticity also with the addition of fibers. It is observed that the experimental values satisfactorily match with the artificial neural network predicted values.