The present disclosure is related to the field of steel slag treatment, and in particular to a process for stabilizing steel slag, the process comprising subjecting the steel slag to an autoclave treatment by use of a high temperature and pressure saturated vapor at a pressure of 2.0 MPa or above. The process provides the slag with reliable volume stability and makes it possible to meet desired requirements of various building materials. Additionally, the process is low cost, non-polluting, and of very high industrial value.

The present disclosure is related to the field of steel slag treatment, and in particular to a process for stabilizing steel slag, the process comprising subjecting the steel slag to an autoclave treatment by use of a high temperature and pressure saturated vapor at a pressure of 2.0 MPa or above. The process provides the slag with reliable volume stability and makes it possible to meet desired requirements of various building materials. Additionally, the process is low cost, non-polluting, and of very high industrial value.

A structural barrier and energy absorbing device comprises a plurality of structural elements. The structural element alone or in a plurality may serve as a traversal impediment or energy absorbing device, such as a pedestrian barrier, vehicular barrier, anti-tank obstacle, ballistic barrier, or the like. The structural element may be a tetrapod such that it comprises an element body having four extension portions that extend outwardly from the interior center to a distal end, such that the structural element maintains an identical orientation and a low center of gravity in each of four resting positions. The structural element may be a solid-state structural element comprised of a particular material or a portable and collapsible structural element wherein the element body comprises an outer skin defining an interior void space, such that during set-up or installation the interior void space may be filled with a filler substance onsite.

A method and system for producing low-alkalinity sulphoaluminate cement with a new mineral system using steel slag. The method includes the following steps: evenly mixing and homogenizing ground steel slag with dry desulfurization gypsum, aluminum ash and carbide slag according to a set ratio; and conveying the homogenized raw meal to a rotary kiln for calcination to obtain cement clinker, where the calcination temperature is 1200° C.-1270° C., and the calcination time is 20-60 min; the alkalinity modulus of the homogenized cement raw meal is 0.81-0.9, and the Fe.sub.2O.sub.3 content is 8-13%. The method breaks through the requirements on contents of calcium, aluminum and iron in traditional sulphoaluminate cement production, and realizes application of a large amount of steel slag.

A method and system for producing low-alkalinity sulphoaluminate cement with a new mineral system using steel slag. The method includes the following steps: evenly mixing and homogenizing ground steel slag with dry desulfurization gypsum, aluminum ash and carbide slag according to a set ratio; and conveying the homogenized raw meal to a rotary kiln for calcination to obtain cement clinker, where the calcination temperature is 1200° C.-1270° C., and the calcination time is 20-60 min; the alkalinity modulus of the homogenized cement raw meal is 0.81-0.9, and the Fe.sub.2O.sub.3 content is 8-13%. The method breaks through the requirements on contents of calcium, aluminum and iron in traditional sulphoaluminate cement production, and realizes application of a large amount of steel slag.

A structural barrier and energy absorbing device comprises a plurality of structural elements. The structural element alone or in a plurality may serve as a traversal impediment or energy absorbing device, such as a pedestrian barrier, vehicular barrier, anti-tank obstacle, ballistic barrier, or the like. The structural element may be a tetrapod such that it comprises an element body having four extension portions that extend outwardly from the interior center to a distal end, such that the structural element maintains an identical orientation and a low center of gravity in each of four resting positions. The structural element may be a solid-state structural element comprised of a particular material or a portable and collapsible structural element wherein the element body comprises an outer skin defining an interior void space, such that during set-up or installation the interior void space may be filled with a filler substance onsite.

A structural barrier and energy absorbing device comprises a plurality of structural elements. The structural element alone or in a plurality may serve as a traversal impediment or energy absorbing device, such as a pedestrian barrier, vehicular barrier, anti-tank obstacle, ballistic barrier, or the like. The structural element may be a tetrapod such that it comprises an element body having four extension portions that extend outwardly from the interior center to a distal end, such that the structural element maintains an identical orientation and a low center of gravity in each of four resting positions. The structural element may be a solid-state structural element comprised of a particular material or a portable and collapsible structural element wherein the element body comprises an outer skin defining an interior void space, such that during set-up or installation the interior void space may be filled with a filler substance onsite.

Method of efficiently manufacturing cement-SCM compositions having improved strength compared to cement-SCM compositions made using conventional methods. The cement-SCM compositions may contain: (A) a fine interground particulate component with (1) a hydraulic cement fraction and (2) a supplementary cementitious material (SCM) fraction; (B) a coarse particulate component comprised of coarse SCM particles not interground with the fine interground particulate component; and optionally (C) an auxiliary particulate component not interground with the fine interground particulate component or the coarse particulate component. A method of manufacturing a cement-SCM composition may be performed by: (A) intergrinding hydraulic cement (e.g., cement clinker) with one or more SCMs to form a fine interground particulate component; (B) blending, without intergrinding, the fine interground particulate component with a coarse particulate component comprised of coarse SCM particles; and optionally (C) further combining, without intergrinding, an auxiliary particulate component with the fine interground particulate component and the coarse particulate component.

Method of efficiently manufacturing cement-SCM compositions having improved strength compared to cement-SCM compositions made using conventional methods. The cement-SCM compositions may contain: (A) a fine interground particulate component with (1) a hydraulic cement fraction and (2) a supplementary cementitious material (SCM) fraction; (B) a coarse particulate component comprised of coarse SCM particles not interground with the fine interground particulate component; and optionally (C) an auxiliary particulate component not interground with the fine interground particulate component or the coarse particulate component. A method of manufacturing a cement-SCM composition may be performed by: (A) intergrinding hydraulic cement (e.g., cement clinker) with one or more SCMs to form a fine interground particulate component; (B) blending, without intergrinding, the fine interground particulate component with a coarse particulate component comprised of coarse SCM particles; and optionally (C) further combining, without intergrinding, an auxiliary particulate component with the fine interground particulate component and the coarse particulate component.

An activated pozzolan composition includes a fine interground particulate blend of an initially unactivated natural pozzolan and a supplementary cementitious material (SCM) different than the initially unactivated natural pozzolan. The initially unactivated natural pozzolan may include volcanic ash or other natural pozzolanic deposit having a moisture content of at least 3%, and the activated pozzolan composition can have a moisture content less than 0.5% The initially unactivated natural pozzolan may have a particle size less than 1 mm before intergrinding with the SCM. The SCM used to activate the initially unactivated natural pozzolan can be initially coarse or granular with a size greater than 1-3 μm and may include granulated blast furnace slag, steel slag, other metallurgical slag, pumice, limestone, fine aggregate, shale, tuff, trass, geologic material, waste glass, glass shards, basalt, sinters, ceramics, recycled bricks, recycled concrete, refractory materials, other waste industrial products, sand, or natural mineral.