A parametric study on alkali activated no fines concrete

Abstract

Pervious concrete is also known as environment friendly concrete as it reduces the storm water runoff. Here in the present study no fines concrete name has been introduce for pervious concrete. Cement which is used to make concrete, contributes tones of greenhouse gas emissions annually to the earth's atmosphere. Therefore, if the cement is replaced by any other binder material then it will be more beneficial towards environment as green house gas emissions will get reduces. Moreover the large amount of availability of fly ash, bottom ash, rise husk ash, GGBFS, lime creates the opportunity for the utilization of these by products as the replacement of cement to manufacture the concrete. The present study focuses on the various binder materials for the replacement of cement. In this major project, the basic information and design parameters of alkali activated no fines concrete such as materials, weight, colour, area, mix proportion, compaction type, curing type, density, mix homogeneity, manufacturing process, cost of production, etc. are to be collected from the literature survey of geopolymer pervious concrete to study the mix proportion and casting procedure of alkali activated no fines concrete. For experimental work Class F fly ash, dehydrated lime and GGBFS from local suppliers has been used to produce alkali activated no fines concrete. Experimental work comprises investigation on void ratio and compressive strength of alkali activated no fines concrete at age of 7 days with. To develop the mix design of alkali activated no fines concrete, the effect of variation in type and proportion of source materials such as 100 % fly ash, 99 % fly ash - 1 % lime and 50 % fly ash - 50 % ggbfs has been investigated. Other parameters includes aggregate content 70 % - 80 %, theoretical void ratio 0, 10 ,20 % alkaline liquid to source material ratio 0.3, 0.4 and 0.5, alkaline liquid ratio 2 and 2.5, concentration of NaOH solution 12M and 14M , extra water content 10 %, rest period 1 day and 2 days, ambient curing and oven curing, compaction effort etc. have been varied throughout investigation. The parameters giving satisfactory and economical results are selected for making alkali activated no fines concrete. The final mix has been casted for the investigation of the properties of the alkali activated no fines concrete i.e. fresh density, void ratio, compressive strength, flexural strength, split tensile strength, permeability. Specimens have been tested at 7 and 28 days, respectively. The other part of the major project consists of the maintenance of portland cement pervious concrete pavement which is constructed at Nirma University campus. Pervious concrete pavement (PCP) is of significant importance in the field of stormwater management in terms of reducing runoff volume. Stormwater managers should initially ensure that PCP adequately performs over time to be able to implement it in a stormwater management system. Performance models are intended to predict the performance of an asset over its service life. To develop a performance model commonly long-term performance data are essential. In the present study the focus is to assess the performance of portland cement pervious concrete pavement which is constructed at Nirma University. Therefore in this part the focus is more on the maintenance of the portland cement pervious concrete pavement. To monitor the portland cement pervious concrete pavement maintenance plan and inspection checklist are prepared. The basic information for the maintenance plan and inspection checklist are collected from the literature surveys and NRMCA catalogues. Maintenance plan consists of the maintenance activities and the frequency of the maintenance activities to be perform on the pavement. Inspection checklist contains the maintenance activities according to the maintenance plan. The considered mix design for portland cement pervious concrete pavement was taken from the past work done at Nirma University. The present study also includes the laboratory results and field investigation of portland cement pervious concrete pavement. The Maintenance activities has been performed on portland cement pervious concrete pavement are infiltration rate, loss of aggregates, collection of water, surface cleaning, cleaning of outlets, removal of vegetation, etc by considering the frequency of activities according to maintenance plan.