A building foundation structure includes a ground improved body obtained by improving a surface layer ground, and foundation concrete placed on the ground improved body on site. The foundation concrete located below a building pillar has an upper part and a lower part having different shapes. The lower part has a reverse trapezoidal sectional shape in a cross section taken along a vertical plane including a horizontal direction perpendicular to a horizontal line connecting building pillars adjacent to each other. The upper part has a brim portion protruding in the first horizontal direction from a side edge at an upper end in the sectional shape of the lower part.

A building foundation structure includes a ground improved body obtained by improving a surface layer ground, and foundation concrete placed on the ground improved body on site. The foundation concrete located below a building pillar has an upper part and a lower part having different shapes. The lower part has a reverse trapezoidal sectional shape in a cross section taken along a vertical plane including a horizontal direction perpendicular to a horizontal line connecting building pillars adjacent to each other. The upper part has a brim portion protruding in the first horizontal direction from a side edge at an upper end in the sectional shape of the lower part.

A wind turbine foundation comprising a concrete support slab having a horizontal rebar grid therein, a concrete pedestal integral with the support slab and having vertical post tensioning elements therein and a plurality of concrete ribs on top of and integral with the support slab and integral with the pedestal, the ribs having rebar therein and extend outwardly from the pedestal, the pedestal, slab and ribs are connected to each other to form a monolithic foundation. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

A wind turbine foundation comprising a concrete support slab having a horizontal rebar grid therein, a concrete pedestal integral with the support slab and having vertical post tensioning elements therein and a plurality of concrete ribs on top of and integral with the support slab and integral with the pedestal, the ribs having rebar therein and extend outwardly from the pedestal, the pedestal, slab and ribs are connected to each other to form a monolithic foundation. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

A wind turbine foundation comprising a concrete support slab having a horizontal rebar grid therein, a concrete pedestal integral with the support slab and having vertical post tensioning elements therein and a plurality of concrete ribs on top of and integral with the support slab and integral with the pedestal, the ribs having rebar therein and extend outwardly from the pedestal, the pedestal, slab and ribs are connected to each other to form a monolithic foundation. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

A wind turbine foundation comprising a concrete support slab having a horizontal rebar grid therein, a concrete pedestal integral with the support slab and having vertical post tensioning elements therein and a plurality of concrete ribs on top of and integral with the support slab and integral with the pedestal, the ribs having rebar therein and extend outwardly from the pedestal, the pedestal, slab and ribs are connected to each other to form a monolithic foundation. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

A wind turbine foundation comprising a concrete support slab having a horizontal rebar grid therein, a concrete pedestal integral with the support slab and having vertical post tensioning elements therein and a plurality of concrete ribs on top of and integral with the support slab and integral with the pedestal, the ribs having rebar therein and extend outwardly from the pedestal, the pedestal, slab and ribs are connected to each other to form a monolithic foundation. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

A wind turbine foundation comprising a concrete support slab having a horizontal rebar grid therein, a concrete pedestal integral with the support slab and having vertical post tensioning elements therein and a plurality of concrete ribs on top of and integral with the support slab and integral with the pedestal, the ribs having rebar therein and extend outwardly from the pedestal, the pedestal, slab and ribs are connected to each other to form a monolithic foundation. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

A fatigue resistant gravity based spread footing under heavy multi-axial cyclical loading of a wind tower. The foundation having a central vertical pedestal, a substantially horizontal continuous bottom support slab, a plurality of radial reinforcing ribs extending radially outward from the pedestal. The pedestal, ribs and slab forming a continuous monolithic structure. The foundation may have a three-dimensional network of post-tensioning elements that keep the structural elements under heavy multi-axial post compression with a specific eccentricity intended to reduce stress amplitudes and deflections and allows the foundation to have a desirable combination of high stiffness and superior fatigue resistance. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

A fatigue resistant gravity based spread footing under heavy multi-axial cyclical loading of a wind tower. The foundation having a central vertical pedestal, a substantially horizontal continuous bottom support slab, a plurality of radial reinforcing ribs extending radially outward from the pedestal. The pedestal, ribs and slab forming a continuous monolithic structure. The foundation may have a three-dimensional network of post-tensioning elements that keep the structural elements under heavy multi-axial post compression with a specific eccentricity intended to reduce stress amplitudes and deflections and allows the foundation to have a desirable combination of high stiffness and superior fatigue resistance. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.