This paper presents the development of ambient temperature cured ultra-high-performance geopolymer concrete (UHPGPC). Ultra-high-performance concrete (UHPC) mixtures were developed by completely eliminating Portland cement and activating industrial by-product materials such as ground granulated blastfurnace slag and silica fume.Local standard sand (maximum size 2 mm), quartz sand (600 ìm) and 0 . 16 mm diameter steel fibres of 13 and 6 mm length were used. Fresh properties (density and flowability) and mechanical properties (compressive strength) of the UHPGPC produced under ambient temperature curing conditions were evaluated. Four mixtures with fibres and one mix without fibre addition were studied as the UHPGPC mixtures. The highest average compressive strengths obtained were 175 MPa for UHPGPC with steel fibres (1% 6 mm and 2% 13 mm) and 124 MPa for UHPGPC without fibres. Prismatic specimens (100 3 100 3 500 mm) were cast to determine the flexural strength, which was found to be 10 . 3-13 . 5 MPa and 9 . 1 MPa for mixes with and without steel fibres respectively. The compressive and flexural strengths obtained in this work are comparable to UHPC strengths presented in the literature. Production of this innovative material with industrial by-products and without the conventional curing regimes used for UHPC will improve sustainability and lead to cast-in-situ applications of UHPC.

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This work describes the experimental investigation on behaviour of reinforced GPC beams subjected to monotonic static loading. The overall dimensions of the GPC beams are 250 mm 9 300 mm 9 2200 mm. The effective span of beam is 1600 mm. The beams have been designed to be critical in shear as per IS:456 provisions. The specimens were produced from a mix incorporating fly ash and ground granulated blast furnace slag, which was designed for a compressive strength of 40 MPa at 28 days. The reinforced concrete specimens are subjected to curing at ambient temperature under wet burlap. The parameters being investigated include shear span to depth ratio (a/d = 1.5 and 2.0). Experiments are conducted on 12 GPC beams and four OPCC control beams. All the beams are tested using 2000 kN servo-controlled hydraulic actuator. This paper presents the results of experimental studies.

In this study, efforts were undertaken to produce ultra-high-strength mortars (UHSM) from conventionally available materials. Selection of mixtures and optimization of mixtures were achieved by adopting the basic principles of UHSM and through trial studies. A preliminary investigation was carried out to assess the effects of different curing regimes on the strength development of UHSM. Effects of fiber addition, heat treatment, and preset pressure on the rate of strength development of UHSM mixtures were individually assessed to better understand their benefits in the production of UHSM. Mechanical properties of the heat-treated UHSM were then investigated to determine the performance of the UHSM developed from conventional materials. Results from this study suggested that for the production of UHSM, a multiple curing regime was best suited and was then used for further studies. Data on strength development indicated that heat treatment increased the strengths by 57% to 75%. With application of preset pressure, the compressive strengths of UHSM were increased significantly by 15% to 18%. The optimum quantity of fibers to produce UHSM was found to be 2% to 3%. Effectiveness of fibers in increasing the strength of UHSM was found to be higher for heat-cured specimens than for normal water-cured specimens. The maximum target strengths obtained from the UHSM were 194 MPa, 24 MPa, and 31 MPa for compression, split tension, and flexure, respectively. The UHSM also showed improved energy absorption and toughness characteristics, especially at higher-fiber dosages.

In a developing country like India, periodic evaluation of low volume urban roads is required to prioritize the order of maintenance and rehabilitation of road network. This paper presents a typical case study of an urban road network of Tumkur city, Karnataka, India. Six roads stretches of the selected road network were investigated for traffic volume, functional and structural condition in terms of CBR value of the subgrade soil, rebound deflection from Benkelman Beam Deflection(BBD) survey, International Roughness Index(IRI) using Machine for Evaluating Roughness using Low-cost Instrumentation(MERLIN) and condition rating based on extent of cracking, patching, rutting and potholes. The structural condition is evaluated using KENLAYER software to obtain the critical strains. Two of the existing measures of pavement condition are used to evaluate the pavement condition and to decide the order of maintenance priority for the selected road network. It is found that the two methods viz Pavement Condition Index (PCI) and Maintenance Priority Index (MPI) do not yield a satisfactory ranking of the maintenance requirement. A more comprehensive prioritization index called Modified Maintenance Priority Index (MMPI) is proposed and is found to give realistic ranking of the maintenance priority requirement of the selected road network.