The compressive strength and elastic modulus of cement asphalt emulsion mortar (CAM) are two fundamental parameters of material design, and their values are highly dependent on asphalt:cement mass ratio (A/C) and temperature. However, there are few quantitative studies about the effect of A/C and temperature on the mechanical properties of CAM. This paper studies the compressive strength and elastic modulus of CAM with varied A/C at different temperatures. A physical and mathematic model is proposed to relate the compressive strength and elastic modulus of CAM to asphalt:cement volume ratio (${\mathrm{V}}_{\mathrm{A}}/{\mathrm{V}}_{\mathrm{C}}$ ) and temperature. The proposed model calculates the compressive strength (or elastic modulus) of CAM by the compressive strength (or elastic modulus) of cement mortar, ${\mathrm{V}}_{\mathrm{A}}/{\mathrm{V}}_{\mathrm{C}}$ , and a parameter $b$ . The parameter $b$ is related to the rigidity and adhesive ability of asphalt binder, and it has a linear relationship with temperature. The proposed model can accurately predict the mechanical properties of CAM with different ${\mathrm{V}}_{\mathrm{A}}/{\mathrm{V}}_{\mathrm{C}}$ and temperatures, and thus it provides a good method to study the mechanical properties of CAM. The limitations of the proposed model are discussed.

Cement asphalt emulsion (CA) mortar is a key material in the nonballast slab track. Its properties are largely dependent on the compatibility between asphalt emulsion and cement. The mixing stability of asphalt emulsion with cement is investigated by analyzing the viscosity of CA paste. Viscosity and the critical particle volume fraction of CA paste are proposed as indexes in evaluating the mixing stability of asphalt emulsion with cement, and factors influencing the mixing stability of asphalt emulsion are studied. Mixing stability is dependent on mixing method, superplasticizer, and emulsion type. The premixing cement method, superplasticizer, and good asphalt emulsion can increase the critical particle volume fraction of CA paste, which is helpful in achieving a low water–to–cement mass ratio (W/C). Anionic emulsion has much better mixing stability with cement than does cationic emulsion. The critical particle volume fraction of CA pastes with anionic emulsion increases stably with the mass rat...