## 1 Introduction  
Cemented Sand Gravel and Rock Dam (CSGRD) is a new environmentally friendly type of dam with characteristics between those of an embankment (soil-rock) dam and a concrete dam developed and promoted by Professor [PERSON] of China, the Honorary President of the International Committee on Large Dams (ICOLD) [1, 2, 3, 4]. It addresses the challenges of breaching in embankment dams due to overtopping and erosion, as well as the high environmental and economic costs of concrete gravity dam construction due to high cement consumption and foundation requirements [5, 6]. Based on the concepts of Hardfill [7] and Cemented Sand and Gravel (CSG) Dams [8, 9, 10], CSGRD further expanded the use of local aggregate [11] sizes from 80 mm to 150 mm and 300 mm for dam and cofferdam construction, respectively. The dam can be built with locally available materials with little or no screening [12]. The materials are cemented with cementitious materials to produce Cemented Sand Gravel and Rock (CSGR) of certain shear strength, as specified by the Technical Guideline for Cemented Materials Dam (SL678-2014) [13; 14; 15]. CSGRD, like a Roller Compacted Concrete (RCC) dam, Hardfill Dam, or Cemented Sand and Gravel (CSG) Dam, has seepage lines along its compacted layers and requires protective watertight layers. It also requires cushion layers for the dam body. Therefore, [PERSON] et al. (2016) recommended that if the Rich-Mix CSGR can attain a frost resistance grade of F300 (attain mass loss of less than 5% or maintain 60% of its initial dynamic modulus after 300 freeze and thaw cycles) and a permeability resistance grade of W12 (i.e., equivalent to a permeability coefficient of 0.13 \(\times\) 10\({}^{-10}\) m/s), it can be used to achieve frost resistance, to construct protective and seepage control layers and cushions, and also applied in anti-carbonation zones in CSGRD. This criterion, however, is flexible depending on the project requirements [1]. Though SL678-2014 specifies the paste margin (\(\alpha\)) \(>\) 1 and mortar margin (\(\beta\)) \(>\) 1, for the Rich-Mix CSGR material, the actual values achieved via experimentation are usually lower or more than required due to the complexity of the experiment, as well as being labor and time-intensive, resulting in an inadequately studied correlation behaviour [14]. The \(\alpha\) value represents the paste volume-to-fine aggregate void ratio, while the \(\beta\) value represents the mortar volume-to-coarse aggregate void ratio [14]. The sizes of the \(\alpha\) and \(\beta\) values reflect the thickness of the excess or wrapping layer of paste and mortar for fine and coarse aggregates, respectively. When \(\alpha\) and \(\beta\) values exceed 1, additional paste and mortar are available for workability margin. The minimum values of \(\alpha\) and \(\beta\) must not fall below 1 to ensure sufficient cohesion and prevent significant mixture segregation during transport, spreading, and compaction. Using this technique to ensure optimum paste and mortar margins in mix proportioning ensures optimum paste and mortar volumes required for the project other than guesswork or a series of trial proportioning methods that waste resources [14]. Again, research has stated that the primary characteristic of cemented sand, gravel, and rock is that, the aggregate used is unscreened, leading to a discrete and fluctuating gradation. To address this challenge, they indicated that, an optimized mix proportion design method can be achieved by adjusting the sand content or sand ratio and optimizing the aggregate gradation as well to control the workability margins [15; 16]. Furthermore, to achieve the desirable workable margin, the cementitious materials-to-mortar ratio of High-Cementitious Paste Roller Compacted Concrete (HCRCC), according to the United States Army Corps of Engineers (USACE), needs to lie in the range of 0.34 to 0.40 [16].