Keywords: pervious concrete, porosity, strength, permeability, recycled concrete aggregate, mix design. 1. Introduction In recent times, major cities around the world have experienced frequent flooding due to the …
Abstract. This paper proposes a conceptual formulation for predicting and controlling the compressive strength of Recycled Aggregate Concrete (RAC) mixtures, by explicitly taking into account the specific features of Recycled Concrete Aggregates (RCAs). In fact, since RCAs are significantly more porous than Natural Aggregates …
Kou et al. ( Kou and Poon, 2013) investigated the long-term properties (up to ten years) of the outdoor exposed RAC consisting recycled concrete aggregate and fly ash as partial replacement of aggregate and cement, respectively. Four replacement ratios of FA to cement in weight, i.e. 0%, 25%, 35% and 55% were considered.
As a fine aggregate, river sand with a fineness modulus of 3.0 and a muck component of 0.7% was employed. Construction waste was used as recycled coarse aggregate with a good gradation of classes I, II, and III as per JGJ/T 240-2011 [37], and the performances are shown in Table 2.Alkali-activated natural aggregate concrete …
The concrete is prepared by mixi ng cement with stones. First, mix 50% water with all coarse aggregate. for 30s; and then, mix the remaining mixed water with cement as h for 90s; and finally, fill ...
Zhang et al. [22] applied RSM to the design of a recycled aggregate permeable concrete mix and found a suitable combination of aggregate gradation and admixture mix. Natalia et al. [23] used the ...
The high porosity of recycled coarse aggregate, which results in recycled aggregate concrete (RAC) more vulnerable to freeze–thaw (FT) damage and chemical attack, is a dominant factor that ...
Recycled aggregate concrete (RAC) enhanced with supplementary cementitious materials (SCMs) presents a sustainable alternative in the construction …
Abstract. An experimental program was carried out to study the properties of concretes with C25/30 and C35/45 resistance classes designed using natural aggregates and recycled ones provided from ...
After demolition of old roads and buildings, the removed concrete is often considered worthless and disposed of as demolition waste. By collecting the used concrete and breaking it up, recycled concrete aggregate (RCA) is created (Fig. 1).This paper focuses on coarse RCA which is the coarse aggregate from the original concrete that is …
The use of recycled aggregate concrete (RAC) is undoubtedly on the increase and further research is required for more appropriate mix design methods. This paper presents the result of investigations into the mix design of RAC. The study examined experimentally two conventional and one unconventional mix design methods. The …
The amount of waste generation for plain concrete, optimal mix (A), and optimal mix (B) was 6412, 2650 and 2215 kg for a 110-year period respectively, i.e., compared to plain concrete, generation of concrete waste by the optimal (A) and optimal (B) mixes was reduced by up to 57% and 65% respectively.
Optimizing mix proportion of recycled aggregate concrete by readjusting the aggregate gradation. Struct. Concr., 22 (2021), pp. E22-E32, 10.1002/suco.201900517. ... RSM-based optimized mix design of recycled aggregate concrete containing supplementary cementitious materials based on waste generation and global warming …
The compressive strength of pervious concrete increased with a reduction in the maximum aggregate size from 20 to 13 mm. The relationship between 28-day compressive strength and porosity for pervious concrete was adversely affected by the use of recycled concrete aggregate instead of natural aggregate.
This paper. is devoted to the studies of material and mechanical properties of recycled aggregate concrete using. packing density method. This paper considers mix of two different aggregate sizes ...
Aggregates are generally thought of as inert filler within a concrete mix. But a closer look reveals the major role and influence aggregate plays in the properties of both fresh and hardened concrete. Changes in …
For the environment protection and sustainable development in building construction, waste concrete can be processed into recycled aggregate to mix the recycled aggregate concrete (RAC). However, the existing mix design methods of RAC were complex, and the mechanical properties of RAC were more weakened than …
This paper puts forward a strength-based mix design method for recycled aggregate concrete using a modified empirical formula. A total of 30 mixes, the amount of cement varies from 300 kg/m 3 to 500 kg/m 3 and the proportion of recycled coarse aggregate ranges from 0% to , were prepared for the regression analysis of …
The compressive strength and the permeability coefficient of recycled aggregate pervious concrete based on this mix proportion are 25.07 Mpa and 6.23 mm/s, respectively, which are in line with the provisions of Technical Specification for Application of Recycled Aggregate Pervious Concrete (CJJ/T 253-2016) and can be used for …
Recycled aggregates have not been pre-saturated and the amount of absorbed water was added to the mixing water. Moreover, since the amount of water is important, an additional quantity of cement was added such that the ratio of total water to cement remains constant. For NAC, the …
First, the waste concrete is broken into demolished concrete lumps with a characteristic size of 60–300 mm to partially replace fresh concrete to form recycled lump concrete [13], [14], [15]. Alternatively, waste concrete can be crushed into recycled aggregate to partially or fully replace natural aggregate to produce recycled aggregate ...
This paper puts forward a strength-based mix design method for recycled aggregate concrete using a modified empirical formula. A total of 30 mixes, the amount of cement varies from 300 kg/m³ to ...
Besides, the mix proportion design methods of normal weight aggregate and lightweight aggregate concrete are given by ACI 211.1 and ACI 211.2, respectively, in which the influence of water/cement ratio on concrete strength is highlighted and the volume fraction of coarse aggregate is determined according to the table obtained from …
Mix Design and Recycled Aggregates Effects on the Concrete's Properties. Research paper. Published: 29 June 2017. Volume 16, pages 973–992, ( …
The concrete mixtures were prepared using Ordinary Portland Cement (OPC) of 53 Grade conforming to Bureau of Indian Standard Specifications (BIS) (IS: 12269–2013) [93], Natural Coarse Aggregate (NCA), Recycled Coarse Aggregate (RCA), clean river sand conforming to grading Zone II (IS: 383–1970) [94] and potable water. …
This paper proposes a conceptual formulation for predicting and controlling the compressive strength of Recycled Aggregate Concrete (RAC) mixtures, by explicitly taking into account the specific features of Recycled Concrete Aggregates (RCAs). In fact, since RCAs are significantly more porous than Natural Aggregates (NAs), the mix …
The use of recycled aggregate geopolymer concrete as structural concrete is not encouraged due to lack of appropriate mix design methodology. The current study aims to develop a new mix design methodology by using fly ash and ground granulated blast furnace slag with recycle aggregate, which is simpler and more consistent …
Abstract This study proposes a new mix design method for C30 recycled concrete using recycled aggregate crushed from different strength source concrete (SC). The dosages of cement, water, sand, and coarse recycled concrete aggregate (CRCA) are the same as the corresponding components in natural concrete, but the …
This article is on the development of a mix design method for self-compacting recycled aggregate concrete (SCRAC) by considering the adhered mortar content (AMC) on the surface of the aggregate.
The effect of mix design parameters and aggregates properties on the compressive strength has been investigated and a model is proposed on the basis of Féret's expression through experimental results and data points available in the literature. ... Omary S, Ghorbel E, Wardeh G (2016) Relationships between recycled concrete …