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Improving the aging resistance of waterproof membranes is very important to extend their service life. In this paper, organic montmorillonite (OMMT) was used to enhance the aging resistance of styrene-butadiene-styrene (SBS) modified bitumen (SMB) for waterproofing. The effect of OMMT on the physical properties, chemical structure, and micromorphology of SMB membranes before and after heat aging were investigated, and the service life of the SMB membranes was predicted based on the Arrhenius model. The results indicated that the high- and low-temperature performance of SMB was improved due to the addition of OMMT, and the optimal dosage of OMMT was 3%. After 20 days of heat aging at 80°C, the alterations of softening point increment, low-temperature flexibility decrement, and viscosity aging index of OMMT/SMB decreased by 1.5°C, 3°C, and 14.7%, respectively, compared with that of SMB, which indicated that OMMT can enhance the aging resistance of SMB waterproof membranes. Fourier-transform infrared spectroscopy indicated that the change of IC═O , IS═O , and IC═C of 3% OMMT/SMB was 53.5%, 45.6%, and 53.2% less, respectively, than SMB after 20 days of heat aging at 80°C, which shows that OMMT can inhibit the change of carbonyl, sulfoxide, and butadiene double bonds of SMB. The gel permeation chromatography showed that OMMT can hinder the degradation of SBS and polycondensation of bitumen during heat aging. The fluorescence microscope showed that OMMT/SMB maintained a more complete network structure than SMB after heat aging. According to the Arrhenius model, based on the 0°C flexibility as the damage point and the temperature of waterproof materials under sunlight being 60°C for an annual sunshine time of 1,200 h, the service life of SMB and OMMT/SMB were predicted to be 16.90 and 21.32 years, respectively. [ABSTRACT FROM AUTHOR]

• OATP enhances high temperature performance of SMAWM. • Compared with ATP, OATP has less influence on low-temperature performance of SMAWM. • OATP significantly improves thermal and UV aging resistance of SMAWM. In order to improve the aging resistance of styrene butadiene styrene (SBS) modified asphalt waterproofing membranes (SMAWM), in this study, vinyltriethoxysilane grafted attapulgite (VTES-g-ATP) and octadecyl-dimethyl-benzyl-ammonium chloride intercalated attapulgite (ODBA-i-ATP) was prepared, respectively. The effects of VTES-g-ATP and ODBA-i-ATP on properties of SMAWM before and after thermal and ultraviolet aging were investigated. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and loss on ignition test indicated that the cationic surfactant octadecyl-dimethyl-benzyl-ammonium chloride (ODBA) was intercalated into the porous structure of attapulgite (ATP), while the coupling agent vinyltriethoxysilane (VTES) was grafted on the surface of ATP. The water contact angles of ATP, VTES-g-ATP and ODBA-i-ATP were 0°, 50.25° and 72.25°, respectively, revealing VTES-g-ATP and ODBA-i-ATP had better hydrophobicity. Compared to ATP, VTES-g-ATP and ODBA-i-ATP effectively improved the softening point and viscosity and had less effect on the low-temperature flexibility of SMAWM. The results of thermal and ultraviolet aging showed that VTES-g-ATP and ODBA-i-ATP were superior to ATP in enhancing aging resistance of SMAWA, particularly ODBA-i-ATP. FTIR analysis showed that ATP, VTES-g-ATP and ODBA-i-ATP effectively inhibited the oxidative polycondensation of asphalt and the degradation of SBS. Considering the balance of physical properties and aging resistance of modified SMAWM, the ODBA-i-ATP was more suitable as an additive for SMAWM, and the optimal dosage of ODBA-i-ATP in SMAWM is 3.0 wt%. [ABSTRACT FROM AUTHOR]

• The pore structure of mortars with FA and BFS was improved by ions chelator, especially for 100%OPC and 50%BFS mortar. • Ion chelator decreased liquid water diffusion and water absorption coefficients of mortars, especially for 100%OPC and 50%BFS mortar. • Ion chelator enhanced crack-healing ability of mortar, thereby reducing the water absorption of pre-cracked mortar specimens. This paper investigated the effect of ion chelator on water dependency of water transport and fixation in mortars with high volume of fly ash (FA) and blast furnace slag (BFS). Ion chelator (CA) as a new type of crystalline admixture could improve self-healing performance of cementitious materials by crack-healing and pore filling. The porosity of mortar was measured by vacuum saturation and pore size distribution of mortar was tested by low-field nuclear magnetic resonance (LF NMR). The water sorption of mortar was evaluated by water vapor adsorption desorption balance. The water transport of mortar with and without crack was tested by capillary water absorption. Based on the experimental results, the water distribution of capillary water absorption in mortar was calculated. Results showed that the pore structure of mortar was improved evidently by CA, and the pores (>1μm) and the total porosity in mortar containing 50 %BFS were significantly reduced. CA had no obvious effect on the water vapor diffusion coefficient of mortar, but has a significant impact on the liquid water diffusion coefficient, especially in pure cement and containing 50 % BFS mortar. The total capillary water absorption and capillary absorption coefficient of mortars were reduced by CA, especially in pure cement and containing 50 % BFS mortar. The addition of CA decreased the water penetration in mortar, the reduction rates of water penetration depth in experimental groups (with CA) at 360 min were 12.4 % (100 %OPC), 6.0 % (30 %FA), 21.3 % (50 %BFS) and 10.8 % (16 %FA 24 %BFS) compared to control group (no CA). After curing for 42d, the normalized water absorption coefficients S" of cracked M100CA and M50BFS50CA were 55.1 % and 72.0 %, respectively. Ion chelator significantly improved internal pore structure and crack healing ability of the mortar containing 50 %BFS, and then delayed the water diffusion. [ABSTRACT FROM AUTHOR]